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Owing to rapid urbanization, coastal regions worldwide are experiencing immense resource and environmental stress. Ecological restoration is vital for maintaining and sustainably developing coastal regions. This study proposed a method for delineating priority areas for ecological restoration based on the social-ecological systems (SES) theory. First, an analytical model was established based on three dimensions: ecosystem function, social system pressure, and SES evolution, for analyzing the social and natural systems of coastal regions. Second, based on the modes of land-sea interaction relevant to ecological restoration, auxiliary marine factors were incorporated to aid the delineation of priority areas for ecological restoration. A case study was conducted on the Dapeng New District of Shenzhen City to validate our method. The marine areas of the Dapeng New District have significantly poorer ecosystem function than its terrestrial areas because of the natural geography of this area and human activities. A total of 43.4% of marine areas require artificially assisted ecological restoration, and inland areas 1.5 km from the shoreline are significant for ecological conservation and restoration. Additionally, estuaries and artificial shorelines should be the focus of ecological restoration work in the study area. This case study proved the efficacy of our method. The findings will serve as a reference for the planning and implementation of ecological restoration plans in coastal regions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A patient with fever, chills, and pancytopenia as major clinical manifestations was presented. To investigate the cause, the patient's peripheral blood was collected for pathogen screening using metagenomic next - generation sequencing (mNGS). The DNA sequence of Leishmania donovani was detected, and Leishmania amastigotes were found in bone marrow smears using microscopy. The case was therefore definitively diagnosed as visceral leishmaniasis, and was cured and discharged from hospital following treatment with liposomal amphotericin B for 14 days. This is the first imported case of visceral leishmaniasis since the founding of Shenzhen City in 1979.

With landsat-series multi-temporal image data, percentage of vegetation cover (PVC) was estimated by pixel dichotomy. The linear regression analysis and center of gravity migration methods were used to explore the characteristics of the spatiotemporal changes of vegetation cover in Shenzhen from 2000 to 2018. The CA-Markov model was combined to predict future land cover in Shenzhen. The results showed that the PVC in Shenzhen demonstrated obvious regional differentiation characteristics from 2000 to 2018. The eastern region occupied larger proportion than the wes-tern part, while the southern region was larger than the north part. This feature exhibited good consistency with regional topographic effect. The spatial migration characteristic of the center of gravity of PVC was from northwest to southeast, and then from southeast to northwest, with a migration rate of 551.2 m·a -1 . This process was closely related to urbanization in Shenzhen. The PVC in Shen-zhen tended to be generally improved from 2000-2018, with a improvement rate of 0.005·a -1 . The percentage of significantly improved and degraded PVC area was 30.8% and 12.8%, respectively. The CA-Markov method was used to predict the land cover/use pattern of Shenzhen in 2024 under two scenarios, theoretical scenario and natural scenario. There was no significant difference in proportion of the area of the land cover/use patterns obtained by the two kinds of prediction method, with the difference threshold being 0-1.2%. Compared with the data before 2018, the proportion of arbor forests and arable land converted into construction land in Shenzhen would be significantly reduced in 2024, whereas the contradiction between supply and demand would be still tense.

The global pandemic of COVID-19 has made it the focus of current attention. At present, the law of COVID-19 spread in cities is not clear. Cities have long been difficult areas for epidemic prevention and control because of the high population density, high mobility of people, and high frequency of contacts. This paper analyzed case information for 417 patients with COVID-19 in Shenzhen, China. The nearest neighbor index method, kernel density method, and the standard deviation ellipse method were used to analyze the spatio-temporal characteristics of the COVID-19 spread in Shenzhen. The factors influencing that spread were then explored using the multiple linear regression method. The results show that: (1) The development of COVID-19 epidemic situation in Shenzhen occurred in three stages. The patients showed significant hysteresis from the onset of symptoms to hospitalization and then to diagnosis. Prior to 27 January, there was a relatively long time interval between the onset of symptoms and hospitalization for COVID-19; the interval decreased thereafter. (2) The epidemic site (the place where the patient stays during the onset of the disease) showed an agglomeration in space. The degree of agglomeration constantly increased across the three time nodes of 31 January, 14 February, and 22 February. The epidemic sites formed a "core area" in terms of spatial distribution and spread along the "northwest-southeast" direction of the city. (3) Economic and social factors significantly impacted the spread of COVID-19, while environmental factors have not played a significant role.

The acceleration of urbanization has aggravated the fragmentation of ecological patches and increased the uncertainty risk of habitat connectivity. In the context of landscape fragmentation, government need to establish sound policies that effectively protect the stepping-stones of habitat connection and realize urban ecological integration. In this study, a circuit theory model was used to identify the potential ecological corridors in the city and corresponding stepping-stone groups, with two important stepping-stone groups selected as our areas of focus. By establishing the potential linkages between stepping-stone nodes, we constructed stepping-stone networks within the potential ecological corridors and formulated four scenarios to analyze the robustness of the stepping-stone networks under different policies. The results show that there are 46 important habitats and 22 potential ecological corridors in Shenzhen, including 22 stepping-stone networks. The most important stepping-stone network in the central Shenzhen area connects 7 important habitats and contains 110 stepping-stone nodes. The most important stepping-stone network in the northeast area of Shenzhen connects 5 important habitats and contains 130 stepping-stone nodes. Comparing the robustness and form of the stepping-stone networks under the four policy scenarios, we found that the centrality of stepping-stones is of great significance for maintaining the connectivity of important habitats. For instance, there are five stepping-stone networks in Shenzhen that have not been successfully protected by existing ecological protection policies because their highly central nodes are vulnerable to threats. This study analyzed the maintenance of habitat connectivity under different ecological protection policies in the process of urbanization and discussed the significance of highly central stepping-stone nodes in maintaining habitat connectivity. With this effort, a new perspective on habitat connectivity protection under landscape fragmentation is provided, producing a reference for the formulation of urban ecological protection policy., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Since the onset of reform and opening up in China, large cities in the nation have been experiencing problems related to limited medical resources. These resource limitations are due to rapid population growth and urban expansion. As the country's fastest growing city, Shenzhen has experienced a substantial misalignment between the supply and the demand of healthcare services. Numerous researchers have analyzed spatial inequity in healthcare services by focusing on the spatial accessibility of medical facilities, such as hospitals, clinics, and community health service centers (CHSCs). However, the issue of inequity in healthcare services for vulnerable groups has largely been ignored. We chose general hospitals (GHs) and CHSCs, which provide direct healthcare services to residents, as the study objects. By performing spatial accessibility analysis using the gravity model and the two-step floating catchment area method, we investigated healthcare services inequity for vulnerable groups based on four dimensions: residential type, age, education level, and occupation. We found that the services provided by GHs cannot meet the demand in Shenzhen. This inadequacy is characterized by spatial centralization and neglect of those who reside in urban villages, who have low education levels, and who are employed in the manufacturing industry. In contrast, CHSCs generally serve a relatively broad population. This phenomenon is related to differences in the land and capital needs between GHs and CHSCs. Our study reveals that an appropriate adjustment of GH location could significantly improve healthcare services inequity. Therefore, to alleviate this inequity, it is particularly necessary to increase the number of GHs in the peripheral circle and in areas with large vulnerable populations, accelerate the implementation of the hierarchical medical system, and promote the transfer of medical resources to grassroot institutes through CHSCs. This study helps improve our understanding of healthcare services inequity in rapid expanding cities, which is of substantial significance for improving the planning and construction of medical facilities, facilitating scientific decision-making, and promoting social equity.

The release of pollutants in soils owing to rainfall is a major challenge related to urbanization. Here, urban soils from different functional zones were collected to evaluate the release risk and estimate their annual release amounts of trace metals (Co and Ni) using multiple techniques, including diffusive gradients in thin-films (DGT), DGT-induced fluxes in sediments (DIFS) model, and Fourier-transform infrared (FTIR) spectroscopy. The results indicate that the average concentration of Co (6.55 mg kg -1 ) was slightly lower than that of the local soil background, whereas for Ni, the trend was reversed. Risk assessments based on total concentrations show that the soil samples were uncontaminated with Co while uncontaminated to moderately contaminated with Ni. However, the mobility coefficients indicate that Co posed low to medium risk, while Ni posed low risk. Hence, further investigation of DGT measurements and DIFS model show that the DGT-measured Co and Ni concentrations were lower than the corresponding concentrations in solution, leading to low R values and the partial resupply of Co and Ni from the solid phase. The FTIR spectra and elemental analysis suggest that because of the electrostatic attraction and complexation of the hydrosilicate minerals and organic matters, the metal resupply was restrained, resulting in them being only a partial resupply. Moreover, the mobility of Co was mainly controlled by the resupply ability, response time, and desorption rate; while for Ni, the particle concentration and porosity played important roles in determining mobility. In addition, the release amounts of the trace metals were quantified using the binary mixing equation. The estimated annual release amounts of Co and Ni in Pingshan District were 0.44-3.54 t and 1.93-16.47 t, respectively. This study provides an effective in-situ method for estimating the release amounts of trace metals in soils during rainfall combining DGT and DIFS model., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A clear understanding of the characteristics of generated household food waste (HFW) is necessary to formulate an effective food waste management policy. The present study has focused on the quantity and composition of generated HFW as well as the driving forces, and further explored potential means of reducing HFW. The quantity of avoidable HFW generated in Shenzhen City in 2015 was estimated to be two-fold greater than that in 2001, which consequently produced 1,378 thousand metric tonnes CO 2 eq. emissions during their ultimate waste disposal. This suggests that HFW prevention can yield great environment benefits by reducing carbon emissions. Based on a survey in which 418 households in Shenzhen City participated, it was apparent that both household size and income are the major drivers to HFW generation. A substantial reduction in HFW generation can be achieved through improvements in consumer behaviors, consciousness and attitudes. Priority should be given to the strategies that can increase people's awareness of HFW induced problems, with the purposes to achieve a more sustainable development., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Diverse species of rodents and shrews, which are abundant worldwide, harbor a variety of viruses; some of these are closely related to human viruses and possess zoonotic potential. Previously studies have demonstrated that the mammarenavirus and hantavirus carried by rodents or shrews could cause diseases in human population. To determine the distribution of zoonotic viruses in Shenzhen city, the major city in southern China with a high population density, we analyzed 225 rodents (Rattus norvegicus and Rattus flavipectus) and 196 shrews (Suncus murinus) from urban and rural districts for the presence of mammarenavirus, hantavirus, and hepatitis E virus (HEV) by RT-PCR targeting the conserved regions. The infection rates for mammarenavirus, hantaviruses, and HEV in rodents and shrews were 3.56%, 6.89%, and 1.66%, respectively. Partial genome fragment analysis indicated that mammarenavirus and hantavirus strains had more than 90% and 99% nucleic acid identity with Cardamones virus and Seoul virus, respectively, which cause diseases in humans. Although the present HEV strains identified are typically found worldwide, phylogenetic analysis demonstrated a divergence of 16%. To our knowledge, the present work is the first report of the prevalence of mammarenavirus, hantaviruses, and rat HEV strains in rodents and shrews from Shenzhen city, China. Our findings highlight the zoonotic potential of rodent- and shrew-borne mammarenavirus and hantavirus, and the biodiversity of rat HEV isolates in Shenzhen city. The present work suggests that utilization of good hygiene habits is important to minimize the risk of zoonosis.