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Rapid economic development, industrialization and urbanization lead to environmental pollution and damage the stability of regional ecosystems. The Yangtze River Delta region is an economically developed region in China, faces the problems of water environment pollution and water ecosystem service degradation. Reasonable assessment of water ecosystem service value (ESV) is of great significance for grasping the status of regional water ecosystem services, improving water ecological environment, and realizing regional sustainable development. This study collects 119 research literature about China, including 156 observations to establish a value transfer database; specially builds a Meta-analysis model including the variables of climate conditions, environmental pollution and environmental protection, then assesses the waters ESV in the Yangtze River Delta using the model and analyzes the changes from 2009 to 2018. The study finds that the location, population density, the area of the site, average annual precipitation, literature characteristics, landscape characteristics, wastewater discharge, environmental protection expenditure, and wastewater treatment costs can affect the water ESV significantly. Based on the meta-analysis benefit transfer model to evaluate the water ESV in Yangtze River Delta region is RMB 177,126 yuan/ hha/year and the growth rate is 27.18%. The place with the highest value per unit area is Shanghai, and the total value in Jiangsu Province is the highest. Economic development, waste water discharge and wastewater treatment costs are the main reasons for the changes and differences in the value of water ecosystem services in the Yangtze River Delta region. The contribution of this study to the field of water ESV assessment is that the meta-analysis model includes a broader set of influencing variables, including landscape, population density, climate change and environmental protection. It provides a practical reference for water ESV assessment on the local scale and a scientific basis for water area management related to the development of water area and ecological compensation, as well as promote the sustainable development of water ecosystems.

Background and aims: Long-term peritoneal dialysis (PD) causes intestinal dysfunction, including constipation, diarrhea, or enteric peritonitis. However, the etiology and pathogenesis of these complications are still unclear and there are no specific drugs available in the clinic. This study aims to determine whether Astragaloside IV (AS IV) has therapeutic value on PD-induced intestinal epithelial barrier dysfunction in vivo and in vitro.Methods: We established two different long-term PD treatment mice models by intraperitoneally injecting 4.25% dextrose-containing peritoneal dialysis fluid (PDF) in uremia mice and normal mice, which were served as controls. In addition, PDF was applied to T84 cells in vitro. The therapeutic effects of AS IV on PD-induced intestinal dysfunction were then examined by histopathological staining, transmission electron microscopy, western blotting, and reverse transcription polymerase chain reaction. The protein levels of protein kinase B (AKT), glycogen synthase kinase 3β (GSK-3β) and β-catenin were examined after administration of AS IV.Results: In the present study, AS IV maintained the intestinal crypt, microvilli and desmosome structures in an orderly arrangement and improved intestinal epithelial permeability with the up-regulation of tight junction proteins in vivo. Furthermore, AS IV protected T84 cells from PD-induced damage by improving cell viability, promoting wound healing, and increasing the expression of tight junction proteins. Additionally, AS IV treatment significantly increased the levels of phosphorylation of AKT, inhibited the activity GSK-3β, and ultimately resulted in the nuclear translocation and accumulation of β-catenin.Conclusion: These findings provide novel insight into the AS IV-mediated protection of the intestinal epithelial barrier from damage via the AKT-GSK3β-β-catenin signal axis during peritoneal dialysis.

Additional file 1. Additional figures and table.

Background and aims: Renal fibrosis is the common outcome in all progressive forms of chronic kidney disease. Unfortunately, the pathogenesis of the renal fibrosis remains largely unexplored, among which metabolic reprogramming plays an extremely crucial role in the evolution of renal fibrosis. Ceria nanoparticles have strong ROS scavenging and anti-inflammatory activity. The present study aims to determine whether CeNPPEG has therapeutic value for renal fibrosis.Methods: Ceria nanoparticles and Ceria nanoparticles-PEG were synthesized according to previously reported procedures with slight modifications. For the in vivo studies, unilateral ureteral obstructive -induced kidney fibrosis was chosen. Through cellular studies, TGF-β1-induced epithelial-to-mesenchymal transition in HK-2 cells of enhanced glycolysis was initially utilized to report the associations among Ceria nanoparticles-PEG, oxidative phosphorylation, glycolysis and renal fibrosis.Results: In this study, Ceria nanoparticles were developed and the Ceria nanoparticles-PEG treatment significantly ameliorated renal fibrosis in unilateral ureteral obstructive mice as well as protected HK-2 cells from transforming growth factor beta1 -induced epithelial-to-mesenchymal transition process. Furthermore, we found that Ceria nanoparticles-PEG suppressed hexokinase 1and hexokinase 2 to block the dysregulated metabolic status, in which damaged epithelial cells take glycolytic metabolism as priority to oxidative phosphorylation, exerting the protective function in the progress of renal fibrosis.Conclusions: The application of Ceria nanoparticles-PEG in this study is attempted to provide another therapeutic option on renal fibrosis.

The bilayer Al 2 O 3 /in-situ SiN x gate dielectric stacks were applied to fabricate high-performance AlGaN/GaN MIS-HEMTs. Both the normally-off and normally-on operations were realized on the ultrathin-barrier Al 0.05 Ga 0.95 N/GaN heterojunctions. Moreover, the low $V_{th}$ hysteresis of 50 mV and subthreshold swing of 70 mv/dec were achieved based on the in-situ SiN x /Al 0.05 Ga 0.95 N interface. The combination of Al 2 O 3 layer and in-situ SiN x layer can also increase the output current and suppress the gate current leakage.

A model predictive voltage control strategy for distribution network is proposed to solve the problem of rapid and frequent fluctuation of voltage in distribution network under large-scale access of distributed energy. Firstly, the voltage prediction model of distribution network based on sensitivity is established, which will analyze and judge the voltage state of distribution network. Then, aimed at the optimal prediction in distribution network voltage deviation voltage optimization control model is established. The plan adjustment amount of the distributed generation system is obtained by solving the model. Finally, the voltage control strategy was tested through a distribution network containing a large amount of distributed energy. Compared with the conventional voltage control method, the feasibility and effectiveness of the proposed voltage control strategy are verified.

Understanding the individual contributions of the factors that influence the electrical properties of a material is important for controlling these properties. In this study, the effects of multiple factors on the electrical properties of thin-barrier AlGaN/GaN heterojunctions with in-situ SiNx caps were investigated using step etching and annealing treatments. The sheet density of the two-dimensional electron gas decreased by 5.9% and 29.5% due to the decrease in the piezoelectric polarization of the AlGaN barrier and the variations in interface charges during SiNx removal, respectively, and it recovered greatly by 72% after annealing-induced surface reconstruction. Capacitance-voltage results clearly revealed few interface traps on the heterojunction with the in-situ SiNx cap. Moreover, a maximum output current of 705 mA/mm and threshold voltage hysteresis below 50 mV were achieved by optimizing the in-situ SiNx interlayer on a thin-barrier metal-insulator-semiconductor structure. This study presents an efficient method for modulating the properties of two-dimensional electron gas and provides insights into the functionality of in-situ SiNx passivation on thin-barrier AlGaN/GaN heterojunctions.

The water-based MoS2 nano-lubricant was prepared and tentatively applied in cold rolling lubricant recirculation systems to investigate its recycling prospect and sustainable lubrication mechanism. The tribological properties and rolling lubrication performance of recycled nano-lubricants with different cycle stages were preliminarily evaluated using four-ball tribotester and two-high rolling mills. To determine the phase transformation of MoS2 in recycled nano-lubricants, the already used MoS2 nano-lubricant was collected, dried and then analyzed by means of X-ray diffraction (XRD). Molecular dynamics simulation was conducted to analyze the specialized lubrication mechanism of reused MoS2 nano-lubricant. The results revealed that the MoS2 was considered to gradually transform into MoO3 during cold rolling process. Those oxidizing metamorphic MoS2 nano-lubricants still had excellent friction reducing and wear resistance. That indicated MoS2 nano-lubricant could be recycled in cold rolling process. The recirculation of MoS2 nano-lubricant reduced the use of lubricants, the discharge of waste liquid and the production cost. Not only the pollution to environment was relieved, but also resources and costs were saved. The calculation results of adsorption energy between nanoparticles and steel surface further demonstrated the absorbing type of lubricating film in different cycle stages. A lubrication model suitable for MoS2 nano-lubricants under steel strip cold rolling lubrication circulation condition was established to explain their sustainable lubrication mechanism.

For the unrestricted investment of face recognition technology, whether it is to protect the safety of people’s life and property or to infringe on people’s basic rights. Face recognition is the most typical one of pattern recognition. It extracts the feature information of face in different ways, compares or tests the collected information with the original information, to realise the record verification of identity or the tracking and positioning of personnel. Nowadays, face recognition technology has been widely used in everyone’s daily life. On the one hand, it brings great convenience to life, on the other hand, whether personal information security and privacy can be guaranteed. Everything has two sides, and face recognition technology is no exception. How to balance the advantages and disadvantages of privacy and security still needs to be further explored.

We show that black phosphorus has room-temperature charge mobilities on the order of 10$^4$ cm$^2$V$^{-1}$s$^{-1}$, which are about one order of magnitude larger than silicon. We also demonstrate strong anisotropic transport in black phosphorus, where the mobilities along the armchair direction are about one order of magnitude larger than zigzag direction. A photocarrier lifetime as long as 100 ps is also determined. These results illustrate that black phosphorus is a promising candidate for future electronic and optoelectronic applications., Comment: 5 pages, 4 figures