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BackgroundWith the widespread use of computed tomography (CT), the detection rate of pulmonary nodules in children has gradually increased. Due to the lack of epidemiological evidence and clinical guideline on pulmonary nodule treatment in children, we aimed to provide a reference for the clinical diagnosis and management of pediatirc pulmonary nodules.MethodsThis retrospective study collected consecutive cases from April 2012 to July 2021 in the Shanghai Children’s Medical Center. The sample included children with pulmonary nodules on chest CT scans and met the inclusion criteria. All patients were categorized into tumor and non-tumor groups by pre-CT clinical diagnosis. Nodule characteristics between groups were analyzed. To establish a clinical assessment model for the benign versus malignant pulmonary nodules, patients who have been followed-up for three months were detected and a decision tree model for nodule malignancy prediction was constructed and validated.ResultsThe sample comprised 1341 patients with an average age of 7.2 ± 4.6 years. More than half of them (51.7%) were diagnosed with malignancies before CT scan. 48.3% were diagnosed with non-tumor diseases or healthy. Compared to non-tumor group, children with tumor were more likely to have multiple nodules in both lungs, with larger size and often be accompanied by osteolytic or mass lesions. Based on the decision tree model, patients’ history of malignancies, nodules diameter size≥5mm, and specific nodule distribution (multiple in both lungs, multiple in the right lung or solitary in the upper or middle right lobe) were important potential predictors for malignity. In the validation set, sensitivity, specificity and AUC were 0.855, 0.833 and 0.828 (95%CI: 0.712-0.909), respectively.ConclusionThis study conducted a clinical assessment model to differentiate benignity and malignancy of pediatric pulmonary nodules. We suggested that a nodule’s diameter, distribution and patient’s history of malignancies are predictable factors in benign or malignant determination.

The blood–brain barrier (BBB) maintains brain homeostasis, regulates influx and efflux transport, and provides protection to the brain tissue. Ultrasound (US) and microbubble (MB)-mediated blood–brain barrier opening is an effective and safe technique for drug delivery in-vitro and in-vivo. However, the exact mechanism underlying this technique is still not fully elucidated. The aim of the study is to explore the contribution of transcytosis in the BBB transient opening using an in-vitro model of BBB. Utilizing a diverse set of techniques, including Ca2+ imaging, electron microscopy, and electrophysiological recordings, our results showed that the combined use of US and MBs triggers membrane deformation within the endothelial cell membrane, a phenomenon primarily observed in the US + MBs group. This deformation facilitates the vesicles transportation of 500 kDa fluorescent Dextran via dynamin-/caveolae-/clathrin- mediated transcytosis pathway. Simultaneously, we observed increase of cytosolic Ca2+ concentration, which is related with increased permeability of the 500 kDa fluorescent Dextran in-vitro. This was found to be associated with the Ca2+-protein kinase C (PKC) signaling pathway. The insights provided by the acoustically-mediated interaction between the microbubbles and the cells delineate potential mechanisms for macromolecular substance permeability.

Socialized agricultural services (SASs) have reshaped the smallholder agricultural system and promoted scale operations in rural China, but little is known about whether and how they affect rural collective action in the irrigation commons. Based on the social-ecological system framework, we apply an ordered probit model and a mediation model to examine the effects of SASs on rural collective action in the commons using a data set consisting of 7737 farm households from 448 villages in 14 provinces in China. We show that SASs have a positive effect on collective action for the governance of the irrigation commons and can slow down and mitigate the negative effect of rural labor migration. In particular, SASs can help improve collective action by enhancing village leadership, fostering agricultural resource dependency, and diminishing economic heterogeneity among villagers. We contribute to the literature by investigating the effects of SASs on rural collective action, which reveals a self-regulatory mechanism inside of the social ecological system enabling it to adapt and restore balance under external shocks. Our findings have implications for the reform of the farming system and governance of the commons.

The shear behavior of the Bolt-Grout interface has a significant effect on the stability of a bolting system. In this paper, a series of shear tests were conducted on Bolt-Grout interfaces, and the effects of rib spacing, rib angles, and normal stress on the shear characteristics and failure modes of the Bolt-Grout interface were investigated. The results showed that the shear strength varied nonlinearly with an increase in rib spacing and angle, and also that it increased linearly with an increase in normal stress. With smaller rib spacings, the effect of rib spacing on peak shear strength was more apparent. The failure modes of the interface can be categorized as shear-slip failure, shear-break failure, and composite failure. The proportion of shear-slip failure and shear-break failure mainly depends on the rib spacing, rib face angle and normal stress.

Do cities with higher administrative hierarchies always enjoy higher intercity connections? Based on an innovation of twin cities (Chengdu-Chongqing) in China, this paper uses machine learning methods (linear model, support vector machines, neural network and random forest) to predict the innovation effect of a new administrative hierarchy on intercity connections. The key findings indicate the following. (1) The innovation effect of administrative hierarchy on intercity connections is asymmetric in twin cities. (2) For the city with a later-higher administrative hierarchy (LHC, Chongqing in this case), the innovation effect of the administrative hierarchy on intercity connections is initially negative (approximately 10 years for Chongqing) and then becomes positive. (3) For the city with an initially higher administrative hierarchy (IHC, Chengdu in this case), the innovation effect is continually positive. (4) The underlying mechanism of the reverse trend for LHC is due to more financial independence, investment in transportation infrastructure and less transaction cost of market access associated with the new administrative hierarchy, which have an innovative effect after a time lag (approximately 10 years for Chongqing). (5) However, IHC enjoys a continual net-positive innovation effect on the intercity connection due to its first-mover advantage on administrative hierarchy and the diffusion effect of LHC. These findings shed light on practical implications that for intercity connections, the primary concern and dominant strategy of innovation is cooperation with the trickle-down rather than the siphon effect. We should tailor different intercity connection strategies for the separate cities in a twin-city pair. This can provide new contributions to the innovation of intercity connections only if the twin cities see one another politically as “siblings” rather than as a “divorced couple”.

ObjectiveTo follow up on the changes in pulmonary function phenotypes in children with asthma in the first year after diagnosis, and explore the risk factors of poor control in children with good treatment compliance.MethodsChildren who were diagnosed with asthma in the Respiratory Department of Shanghai Children's Medical Center from January 1, 2019 to December 31, 2020 and were re-examined every 3 months after diagnosis for 1 year were continuously included, regardless of gender. We collected the clinical data, analyzed clinical characteristics of the different pulmonary function phenotypes at baseline and explored risk factors of poor asthma control after 1 year of standardized treatment.ResultsA total of 142 children with asthma were included in this study, including 54 (38.0%) with normal pulmonary function phenotype (NPF), 75 (52.8%) with ventilation dysfunction phenotype (VD), and 13 (9.2%) with small airway dysfunction phenotype (SAD) in the baseline. Among them, there were statistically significant differences in all spirometry parameters, age, and course of disease before diagnosis (P

The prevailing literature has extensively explored the economic ramifications of land reallocation; however, its impact on commons governance remains underexamined. This study, using the agricultural irrigation system in rural China as an example, empirically investigated how land reallocation affects collective action. Survey information from 6298 households, spread across 461 villages in 20 Chinese provinces, served as the basis for the analysis. Our findings suggest that land reallocation is unfavorable for irrigation collective action, but the presence of informal organizations and effective leadership within the village can help ameliorate these negative effects. This research contributes to a more comprehensive understanding of the nexus between land reallocation and irrigation collective action, offering potentially valuable policy insights for countries or regions worldwide that grapple with land reallocation issues.

Irrigation is key for agricultural production and public affairs in China. Canal irrigation has been the dominant form of irrigation in China for over two thousand years, but this is changing dramatically in contemporary China. Official government data and observational studies prove that canal irrigation has sharply declined in China in the past several decades. This paper explores the causes and influences associated with this decline. We use the social-ecological systems (SES) framework to diagnose the causes of the decline of canal irrigation and identify the significant influences on it. The broader contextual variables of industrialisation, urbanisation, policy, marketisation and technological progress influence resource systems, farmers and governance systems, which, in turn, have jointly led to the decline of canal irrigation. This study also considers the economic, social and ecological consequences of such a shift in irrigation pattern. The decline of canal irrigation may be inevitable in the transformation from a rural to a modern society. However, we must be aware of its costs and risks. To maintain the effectiveness of rural irrigation during the transformation to a modern society, we propose three implications of the decline of canal irrigation.

As the largest developing country, China has permanently attached great importance to cultivated land protection. However, due to the different rules of cultivated land identification in the second and third national land surveys, the cultivated land area in the two surveys has changed greatly. Some agricultural lands in the south, such as plantations, forests, grasslands, aquaculture ponds, etc., belonged to cultivated land during the second survey, but they were identified as non-cultivated land in the third national land survey. This change has led to a sharp reduction in the area of cultivated land in some places. In order to calculate the actual change in the area of cultivated land since the second survey and provide a reasonable basis for the standard of cultivated land protection, this paper takes Gaochun District, a developed area in China, as an example; interprets the images of the second national land survey period with the deep learning network HRNet; and compares the results with the second and third national land survey rules. The results show that the actual reduction of cultivated land in Gaochun District in the past ten years accounts for 35.1% of the reduction of cultivated land in the two land surveys, while the reduction of cultivated land caused by the change of cultivated land identification rules accounts for 64.9% of the reduction of cultivated land in the two land surveys, indicating that the significant reduction in local cultivated land was mainly caused by the changes in the rules, and these cultivated land reduction behaviors existed before the second survey.

Ostrom’s Design Principles (DPs) are believed to be a set of the best practical guidance for governing natural resources, but applying the DP theory should consider the local context, especially the political context, which has been examined little so far. Using the Institutional Analysis and Development (IAD) framework as a conceptual and analytical lens, this paper examines the impact of authoritarian context on self-governance in China. Based on the results of Barnard’s test and Crisp-set Qualitative Comparative Analysis (csQCA), our comparative analysis of nine Water Users Association cases provides consistent evidence that supports the DP theory generally on all outcome dimensions. But self-governance under authoritarianism has unique characteristics and its operation depends on proper design of institutional configuration in accordance with context. Our analysis highlights the influence of resource intervention and leadership intervention. It sheds new insights for understanding the significant impacts of the authoritarian context on institutional design of common-pool resources.

An analysis of the evolution of urban three-dimensional morphology (EUTM) can comprehensively explore the processes and mechanisms of urban evolution and provide a basis for urban design and land use administration. Based on the three-dimensional model of urban built-up areas in two periods, this paper establishes a quantitative index system for the EUTM and discusses the methods of generating isoline maps for each index. The idea of making integrated partition map of urban three-dimensional morphology is developed according to a multidimensional feature space classification method. A quantitative analysis of the EUTM in Nanjing is carried out by using two types of maps.

The diseconomies of scale found in smallholders’ agricultural production is a common problem faced by global agricultural development. Notable examples of regions in which this occurs include Central and Eastern Europe, India, Brazil, and China. Smallholders usually differ in their demands for socialized agricultural services due to scattered farmland, various soil conditions, different selections of crop varieties, and diverse farming arrangements. Such differences make it difficult for smallholders to cooperate on farmland scale management, resulting in a collective action dilemma. Based on the Institutional Analysis and Development framework, this paper provides insights into the influencing factors and effects of smallholders’ utilization of socialized agricultural services and constructs a cooperative mechanism for the purpose of solving the collective action dilemma in rural areas of China. We found that household characteristics, biophysical conditions, attributes of community, and rules-in-use jointly generate the action situation in the process of smallholders’ cooperative utilization of agricultural socialized services. Among them, the rules-in-use not only have a direct impact on the action situation but also regulate the role of the other three sets of factors. Various factors and mechanisms affecting the cooperative utilization of socialized agricultural services by smallholders interact in the action arena and finally form relevant outcomes that can deal with the diseconomies of farmland fragmentation. These outcomes will be fed back to each external variable again along the feedback path, so as to promote the system and create a virtuous circle. This study provides a theoretical contribution to understanding smallholders’ cooperation in the process of agricultural large-scale operation, especially in regions and countries with a large number of smallholders.

Much is known about collective action in the commons but little is known about the effects of migration as an exogenous shock. We study the case of China where at least 280 million people have migrated from the rural areas to the cities over the last four decades. We apply the social-ecological system (SES) framework along with the theory of collective action using survey data from 1985 households in 20 provinces throughout China. Data was analyzed using confirmatory factor analysis, ordered probit regression with instrumental variables, structural equation modeling, and interaction effects analysis. We find that migration exerts a significant negative effect on collective action in the commons and its effect is mediated by four mechanisms: resource dependence, leadership, social capital, and sense of community. Of these, resource dependence and leadership account for about two-thirds of the total effect. The SES framework has been shown to be a useful tool for empirically studying complex, multi-variable, nonlinear, cross-scale, and dynamic social-ecological systems.

The diverse value of rural areas has been gradually highlighted, and promoting the sustainable development of rural areas with the theoretical guidance of rural multifunction is the key to realizing rural revitalization. This study defined the concept of rural multifunction from the perspective of resident’s demands and divided it into five main functions including rural agricultural production, nonagricultural production, living, ecological environment, and social security. By constructing the evaluation index system of rural multifunction, we analysed the spatial distribution characteristics of 160 villages of Jingjiang in Jiangsu Province. And functional combinations were identified to select targeted rural development paths oriented by balanced development of rural multifunction. The results showed the following. (1) The development of various rural functions in Jingjiang city was uneven, and agricultural production function still dominated. (2) The villages with strong agricultural production function were mainly concentrated in the northwest, while the villages with a high level of nonagricultural production function were mostly distributed in the industrial parks or around towns. There is still much room for improvement in social security function, especially in areas dominated by nonagricultural production. Nonagricultural production function had a negative effect on the ecological environment function, which is contrary to the agricultural production function. (3) Balanced development rather than equal development of rural functions should be pursued to achieve multifunctionality. Scientific guidance for the functional growth of villages in Jingjiang city and theoretical support for the microscale evaluation of rural multifunction and its application were provided by the research results.

Farmland scale management represents an inevitable trend toward global modern agriculture. In the new development context, the key to solving the tough problem of the insufficient supply of rural public goods is to effectively improve the enthusiasm of farming households to participate in rural collective action in countries with a small arable area per capita, such as India, China and countries in Eastern Europe. This paper adopts the Institutional Analysis and Development (IAD) framework in the context of a land system with Chinese characteristics, and uses sample data of 3663 rural households in 17 provinces to study the impact of farmland scale and various relevant systems on farming households’ participation in rural collective action. We found that the advantages of collective action, such as reduced production costs, enhanced risk resistance and improved production efficiency, can offset the disadvantages incurred by free-riding behavior, and the expansion of farmland scale can significantly facilitate rural collective action. Additionally, as the farmland scale expands, stable farmland tenure and reasonable farmland tenure transfer can help to optimize the allocation of arable land resources, increase investment, and reduce free-riding behavior, thus effectively stimulating farming households to actively participate in collective action. However, since socialized agricultural services lead to the separation of the suppliers and the users of rural public goods, the expansion of farmland scale shows a negative effect. Therefore, in the context of the continuous migration of the rural population to cities, a stable farmland tenure adjustment mechanism should be established, while the balance between farmland tenure transfer and socialized agricultural services, in pushing forward rural collective action, should be emphasized, so as to ensure the effective supply of rural public goods in propelling farmland scale management. Especially in promoting the development of socialized agricultural services, more attention should be paid to specifying the responsibilities and obligations of the main provider of commercialized services in the supply of rural public goods.

In the context of the transition from “Native-rural China” to “Urban-rural China”, suburban villages have undergone rapid reconstruction of format, industry, and function. Aiming to reveal the evolution characteristics and driving forces, this study selected She Village, located in suburban areas of Nanjing, to analyze the changes of both dominant and recessive morphology of land use by employing participatory rural appraisal, remote sensing, and geographic information systems. The results showed that She Village witnessed three stages, including industrial development, ecological restoration, and service industry development, from 1980 to 2018, with more diversified management modes, multifunctional land use, and intensified land fragmentation. The drivers included natural resources, population growth, policy of Grain for Green, urban market demand, etc., the intensity of which showed trends of “increase–increase–increase”, “increase–decrease–decrease”, “periodically intermittent”, and “increase–decrease–increase” in turn. The tourist villages undergo three stages of industrial development, agricultural development, and service industry development, with periodical characteristics driven by top-down policies, the endogenous force of the village, and the radiation and diffusion of the city. This research deepens the understanding of the development process of suburban villages and provides a reference for land policy making and planning in other similar villages.

Water trading markets have been introduced in many countries as a means to alleviate water scarcity. However, the performance of water markets varies greatly across different countries, and in only very few countries do they work well. In this study, a two-sector water rights trading model is developed and applied to a case study in China. The results suggest that arable land per farmer is a key factor that affects the performance of water markets in China. This is positively correlated with traded water volume, with the market’s economic efficiency, and with the social welfare the market brings. Although the model simulation ignores other factors, this problem can be solved by selecting a suitable research area. These findings suggest that water markets may be less likely to be effective in countries with small arable land per farmer.

Two types of farmer-level mechanisms have been traditionally adopted to increase agricultural water use efficiency in northern China: pricing mechanisms and tradable water rights systems. However, the reluctance of policymakers to exacerbate farmers’ burdens has rendered pricing mechanisms politically infeasible, while tradable water rights systems involve prohibitively high transaction costs in rural China. An experiment conducted in 2005 in the Taocheng District of Hebei Province created a new kind of water-saving mechanism that involves a number of institutional innovations, including “flexible total management”, “collect then refund” and “collect and subsidize, then refund”. This paper evaluates the district’s water-saving mechanisms based on efficiency, equity and operability criteria. The results of the analysis demonstrate that the “collect then refund” mechanism can more effectively enhance water use efficiency and reduce farmers’ burdens than water pricing instruments, tradable water rights systems and flexible total management. Adequate infrastructure and trusted institutions are identified as necessary prerequisites for the successful implementation of the new water-saving mechanism. We believe the new mechanism has great potential to be scaled up.

Water resources management is increasingly important for sustainable economic and social development. A coherent division of the development stages is of primary importance for selecting and implementing related water resource management strategies. Using evolving supply⁻demand relationships, this paper proposes a framework that considers water development stages to present a series of dynamic relationships between water demand changes and overall economic development. The framework is applied to China to advance the understanding of how demand evolves at different stages of water resources development under specific socioeconomic circumstances, and of strategic choices in general. The case of China explains how water resources management has gradually improved during distinct socioeconomic development stages. It illustrates the varieties and effectiveness of water policies made to adapt to changing demand over the course of socioeconomic development. The framework can be potentially applied to other countries or regions to identify the development stage in order to select proper water management strategies.

Backfill mining is an effective way to control ground subsidence and govern gangue. To solve the problem of thin coal seam mining under villages, a new thin seam backfill mining technology was proposed. This paper investigated a reasonable proportion of filling materials by experiments, designed the filling system and introduced key technologies for thin seam working face filling. Finally, an industrial test of thin seam backfill mining technology was carried out in the C1661 working face, Beixu Coal Mine. The results show that the developed filling material meets both the pumping liquidity and strength requirements of the filling body during the early and late stages. The design and equipment selection of the paste filling system were reasonable. By using the key technologies for thin seam working face filling, the time needed for working face filling, the connection and disconnection of the filling pipeline and gob-side entry retaining were all greatly shortened. The labor intensity of the workers was reduced, and the mechanization level of the mine was improved. A fill mining length of 480 m was successfully completed. With effective roof subsidence control, the ground subsidence can be reduced, and good results can be achieved. This study can contribute to the development of backfill mining in thin coal seams.

Background: With the widespread use of computed tomography (CT), the detection rate of pulmonary nodules in children has gradually increased. Due to the lack of epidemiological evidence and clinical guideline on pulmonary nodule treatment in children, we aimed to provide a reference for the clinical diagnosis and management of pediatirc pulmonary nodules. Methods: This retrospective study collected consecutive cases from April 2012 to July 2021 in the Shanghai Children's Medical Center. The sample included children with pulmonary nodules on chest CT scans and met the inclusion criteria. All patients were categorized into tumor and non-tumor groups by pre-CT clinical diagnosis. Nodule characteristics between groups were analyzed. To establish a clinical assessment model for the benign versus malignant pulmonary nodules, patients who have been followed-up for three months were detected and a decision tree model for nodule malignancy prediction was constructed and validated. Results: The sample comprised 1341 patients with an average age of 7.2 ± 4.6 years. More than half of them (51.7%) were diagnosed with malignancies before CT scan. 48.3% were diagnosed with non-tumor diseases or healthy. Compared to nontumor group, children with tumor weremore likely to havemultiple nodules in both lungs, with larger size and often be accompanied by osteolytic or mass lesions. Based on the decision tree model, patients' history of malignancies, nodules dia meter size=5mm, and specific nodule distribution (multiple in both lungs, multiple in the right lung or solitary in the upper or middle right lobe) were important potential predictors for malignity. In the validation set, sensitivity, specificity and AUC were 0.855, 0.833 and 0.828 (95%CI: 0.712-0.909), respectively. Conclusion: This study conducted a clinical assessment model to differentiate benignity and malignancy of pediatric pulmonary nodules. We suggested that a nodule's diameter, distribution and patient's history of malignancies are predictable factors in benign or malignant determination. [ABSTRACT FROM AUTHOR]