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The rapid development of China's new urbanization has created favorable conditions for economic growth and social development. Urbanization includes population urbanization and land urbanization, among which land urbanization leads to land ecological security problems. At present, there is a lack of comprehensive understanding of land ecological security in China's new urbanization construction. This paper aims to fill the gap by systematically combing relevant literature on the connotation, status, and governance of land ecological security in China's new urbanization. Literature review shows that China's land ecological security is still at a low level, and the new urbanization construction has significant impacts on land ecological security. Land contamination is the most critical factor threatening land ecological security, and there are differences in the levels of land contamination and types of pollutants in different new urbanization construction forms. According to an example of land ecological security governance with enterprises as the main body and multiple subjects cooperating, the governance of land ecological security needs to integrate a variety of different subjects to coordinate governance. Future research directions should focus on the construction of land ecological security assessment index system, development of land contamination multi-level control technology, and construction of multi-subject collaborative governance model with "government-enterprise-social organization-residents." [ABSTRACT FROM AUTHOR]

DNS filtering is the practice of blocking access to certain sites for a specific purpose, often content-based filtering. Unlike previous studies that focused on the behavior of national-level DNS filtering itself (e.g., location of filtering devices), we demonstrate and evaluate in depth the impact of DNS filtering on different types (public, ISP, and open) of DNS resolvers in the censored networks. In particular, we actively send DNS queries for 83 well-selected domain names to three types of DNS resolvers and keep track of the resolvers' responses changing over time and space in China. Here, we present the results of our system running for 40 days, during which we obtained a total of 1.7 billion DNS records. Using these collected data, we found that specific DNS resolvers are unaffected by DNS filtering devices and can respond with the correct IP addresses for particular blocked domains. Furthermore, we revealed that three factors should be considered to evaluate the impact of a country-level DNS filtering mechanism: DNS resolver, client location, and blocked domain. Finally, we propose and implement a system to identify the correct IP addresses of blocked domain names in censored networks based on the characteristics of country-level DNS filtering. [ABSTRACT FROM AUTHOR]

The root server is at the top of the domain name hierarchical structure. To improve root service performance, each root deploys anycast nodes worldwide. What is the actual service performance of these nodes after deployment? We analyze the service performance of the root anycast nodes deployed in China based on the active measurement data detected by the VPs of different ISPs in different geographical locations. From the analysis, we find that the resolution performance of the roots with anycast nodes deployed in China is higher than that of roots without deployment. However, users of different operators have significant differences in accessing the root servers, such as parsing time, hitting anycast nodes, and most anycast nodes only providing services for one operator, limiting the service scope and reducing the service performance. The analysis results can help the root management and introduction institutions master the actual service status of the root servers, which can be used to optimize the performance of the existing root anycast nodes and provide a basis for deploying new root anycast nodes in the next step. Finally, we find that 67 top-level domain names are hijacked on the resolution path based on the measured data. [ABSTRACT FROM AUTHOR]

A large number of domains are abused every day for cybercrime. At the same time, the fight against abusive domains is not the fight of one person or organization but a battle that requires the cooperation of the entire community. However, very little research has been done to quantify the positive benefits of this strategy for dealing with abusive domains. As a result, using pornography and gambling domain names as examples, we present the first empirical study evaluating the usability and effectiveness of all Internet entities (e.g., registrars and hosting providers) in the DNS ecosystem for receiving and handling abusive domain reports. First, the paper thoroughly demonstrates the mechanisms for receiving and handling abusive domain reports at various Internet entities in China. Second, we select and report the appropriate 2433 abusive domains to 43 service providers across six categories of Internet entities. Finally, we discover the methods and response time used by each Internet entity to handle abuse reports based on the changes in reported domains. Based on the above data, we analyze and evaluate the effectiveness of Internet entities in dealing with abusive domains. Moreover, we indicate the scope of protection and disadvantages of each method, i.e., whether the abusive domain can escape handling. The paper aims to provide a more detailed overview and reference for the security communities, service providers, and Internet entities concerned with dealing with abusive domains. [ABSTRACT FROM AUTHOR]

The construction of "sponge city" made the belts on both roadsides be built in the form of bioretention tanks, resulting in runoff pollutants were accumulated in the bioretention tanks. To identify the pollution level and source of polycyclic aromatic hydrocarbons (PAHs) in the bioretention tanks, the soil samples were collected on the eight typical roads of the sponge city. The total contents of ∑PAHs in the bioretention tanks were 10,524–20,462 μg/kg (mean 15,029 μg/kg), and the pollution level of PAHs in the non-flood season was significantly higher than that in the flood season. The PAHs in bioretention tanks were dominated by 4-ring PAHs, with a proportion of 39.36%. The characteristic ratio method was proposed to identify the chemical source of PAHs, and the results indicated that PAHs in the bioretention tanks were mainly supplied by the combustion source and petroleum source. The ecological risk quotient (RQ) values showed that the accumulation of PAHs in the bioretention tank had certain potential ecological risks, and the RQ values of pyrene (PYR) were the highest. Incremental lifetime cancer risks (ILCR) indicated that PAHs in soil posed negligible cancer risks by inhalation way, but much stronger risks by dermal and ingestion ways. The roads with the highest and lowest PAHs content were selected for microbial ecology analysis, and the microbial abundances showed significant decreasing trends from the flood season to the non-flood season. The PAHs accumulated in the bioretention tanks had significant impacts on the microbial community, which made the microorganisms tend to PAHs-degrading bacteria. • PAHs showed different accumulation levels in road green infrastructures of sponge city. • The combustion source was the main source of the PAHs in bioretention tanks. • Pyrene (PYR) in the bioretention tank had higher potential ecological risks. • There were potential carcinogenic risks caused by dermal and ingestion ways. • The accumulation of PAHs made microorganisms tend to PAHs-degrading bacteria. [ABSTRACT FROM AUTHOR]

As the bioretention facilities have been extensively built in the construction of "Sponge City" in China, urban non-point source pollutants could be effectively controlled. The influences on microbial community in three bioretention facilities with different underlying types/built times at field scale were studied. The results showed that nutrient loads in road runoff were 1.1–3 times higher than of roof. Compared with the other two rain gardens, the bioretention tank (BT) was relatively stable and showed >90% nutrient load reduction rates. The nutrients brought by the stormwater runoff changed the original habitat in the soil. Nutrient removal led to the deterioration of the living environment of microorganisms, and then the number of microorganisms and diversity changed. Ten dominant bacteria species were found in the facilities, and Proteobacteria were the most dominant bacteria phyla, with the relative abundances all >30%. Suspended solids were found to be the most important factor and had a high correlation to the most dominant microorganisms. With the increased operation period, the microorganism species tended to be concentrated on Proteobacteria , resulting in decreases of other functional microorganisms. The bioretention facility with the road underlying had the lowest microbial diversity, and the built time was the factor that had the greatest impact on microbial diversity. Based on these results, the future design and construction of bioretention facilities should consider the risk after nutrients entered the bioretention facility and the changes in microbial diversity. [Display omitted] • The nutrient removal effects of bioretention facilities with different underlying types/built time were monitored. • The changes of TOC and nutrients (N and P) contents were studied. • The evolutions of the microbial communities were explored. • The relationship between soil nutrient contents and microorganisms was built. • The influences of different design types on the microbial diversity were determined. [ABSTRACT FROM AUTHOR]

• Field performance data were obtained for four typical LID facilities. • Exceedance probabilities of effluent concentration is reduced obviously. • The weighted annual load reduction is more than 60% and stable. • An estimation method for LID extent and cost in urban built-up areas is proposed. Field studies are valuable because of the insufficient number of field performance data in low-impact development (LID)-related research. Four typical LID facilities in northwest China were built and monitored. These facilities differ in their impervious/pervious bottom, inflow underlying surface, media types, and combinations. The water volume reduction of impervious rain garden filled with native loess decreases by approximately 20% when the total daily rainfall levels gradually increase from light to heavy. Several technical measures, such as media modification, setting internal storage area, reducing drainage area, and increasing media thickness, have been taken to improve the runoff regulation effect. The volume reduction rate in light and medium-sized rainfall (daily rainfall totals < 25 mm) is above 68.2% for two improved facilities, namely, mixed media rain garden and layered media bioswale. For impervious native loess rain garden, mixed media rain garden, and layered media bioswale, the median values of inflow total suspended solid (TSS) event mean concentrations (EMC) are reduced from 43.5 to 68.5 mg/L to 22.4–24.3 mg/L. In accordance with the Class IV limits of Surface Water Environmental Quality Standards (total nitrogen (TN) = 1.5 mg/L; total phosphorus (TP) = 0.3 mg/L), the probabilities of the effluent TN concentration exceeding the IV limit are 32.7%, 42.3%, and 19.8% for the three facilities. The exceedance probabilities for TP are 18.5%, 6.5%, and 8.9%. The weighted results indicate that the annual load reduction rate is more stable than the fluctuating concentration removal, which is above 60%. An approach to estimate the total scale of LID construction was established on the basis of rainfall level proportion, land use types, and monitored data. When native loess and mixed media rain garden are applied in building areas and layered media bioswale is applied in road area, the LID implementation cost is approximately 36.0 billion CNY until 2030 for Xi'an City. [ABSTRACT FROM AUTHOR]

Background: With the fast growth of the older population and the increasing rates of chronic illnesses, the demand for hospice care is increasing at a rapid pace. This is bringing great challenges to the healthcare system in China. Given that nursing students will be the main healthcare workforce in the future, and as such, have responsibilities to prepare for these challenges. Therefore, understanding nursing students' perspectives and attitudes towards hospice care in China is important to promote the development of hospice care services., Objectives: To explore the perspectives and attitudes of Chinese nursing students towards hospice care., Method: The descriptive phenomenology of a qualitative approach was used for the study. Data were collected through semi-structured individual interviews from 11 nursing students in China between April and June 2021. Data were analysed using Colaizzi's seven-step approach., Findings: Three main themes were identified: (1) Lack of knowledge and skills; (2) lack of clinical experience; and (3) needs for service improvement. These findings indicated the problems of hospice care education and hospice care services in China., Conclusion: The nursing students in this study lacked theoretical knowledge and the practical skills of hospice care. This suggests that medical educational institutions and the government should take action to increase hospice care training for nursing students, in order to increase the capacity and availability of hospice care services. It also informs policy-makers, health professionals, and health educators about the further need for the development of hospice care services in China., Competing Interests: Declaration of competing interest The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2022. Published by Elsevier Ltd.)

Rhododendron micranthum is used traditionally as a remedy for the treatment of chronic bronchitis in China. To clarify the chemical basis and provide a reference for the rational use of this medicinal plant, a phytochemical study was carried out on the twigs and leaves of R. micranthum, which afforded eight new compounds (1-8) and eight known compounds (9-16). Their structures were rigorously determined by comprehensive HRESIMS, NMR and electronic circular dichroism (ECD) analyses. The anti-inflammatory activities of these compounds were evaluated. Compounds 3, 13, and 14 suppressed the transcription of the NF-κB-dependent reporter gene in LPS-induced 293T/NF-κB-luc cells at 10 μM, while no effect on cell viability was observed., (Copyright © 2019 Elsevier B.V. All rights reserved.)