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Acer palmatum (A. palmatum), a deciduous shrub or small arbour which belongs to Acer of Aceraceae, is an excellent greening species as well as a beautiful ornamental plant. In this study, a high-quality chromosome-level reference genome for A. palmatum was constructed using Oxford Nanopore sequencing and Hi-C technology. The assembly genome was ∼745.78 Mb long with a contig N50 length of 3.20 Mb, and 95.30 % (710.71 Mb) of the assembly was anchored into 13 pseudochromosomes. A total of 28,559 protein-coding genes were obtained, ∼90.02 % (25,710) of which could be functionally annotated. The genomic evolutionary analysis revealed that A. palmatum is most closely related to A. yangbiense and A. truncatum, and underwent only an ancient gamma whole-genome duplication event. Despite lacking a recent independent WGD, 25,795 (90.32 %) genes of A. palmatum were duplicated, and the unique/expanded gene families were linked with genes involved in plant-pathogen interaction and several metabolic pathways, which might underpin adaptability. A combined genomic, transcriptomic, and metabolomic analysis related to the biosynthesis of anthocyanin in leaves during the different season were characterized. The results indicate that the dark-purple colouration of the leaves in spring was caused by a high amount of anthocyanins, especially delphinidin and its derivatives; and the red colouration of the leaves in autumn by a high amount of cyanidin 3-O-glucoside. In conclusion, these valuable multi-omic resources offer important foundations to explore the molecular regulation mechanism in leaf colouration and also provide a platform for the scientific and efficient utilization of A. palmatum.

Diabetic nephropathy is a serious complication of diabetes. Hyperoside has been widely reported to ameliorate diabetes-associated disease. The current study is designed to explore the mechanism of hyperoside in diabetic nephropathy. In the present study, high glucose was used to treat podocytes. Diabetic nephropathy mice models were established by high-fat feeding followed by multiple low dose injections of streptozocin. Western blot analysis was conducted for detection of extracellular matrix accumulation, inflammatory response and cell apoptosis. We found out that hyperoside improved high glucose-induced cell injury. Additionally, hyperoside prevented mice with diabetic nephropathy from diabetic symptoms and renal dysfunction. Mechanistically, hyperoside inhibited the mRNA and protein expression of APC. MiR-499-5p was found to be an upstream negative mediator of APC, and hyperoside induced the upregulation of miR-499-5p. MiR-499-5p bound with the 3' untranslated region of APC to inhibit its expression. Finally, rescue assays revealed that the suppressive effects of miR-499-5p overexpression on renal dysfunction were rescued by upregulation of APC in mice with diabetic nephropathy. In conclusion, these findings indicated that hyperoside ameliorates diabetic nephropathy via targeting the miR-499-5p/APC axis, suggesting that hyperoside may offer a potential tactic for diabetic nephropathy treatment.

Considering the rigid-flexible coupling system of 5 MW wind turbine, the static pressure, fluid temperature, Mach number, vorticity, shear stress and velocity distribution of tower flange are obtained under the combined action of wind shear and fluctuating wind. The dynamic response of rigid-flexible coupling structure is studied by the combined action of the whole vibration and local vibration of 5 MW wind turbine. Through the analysis of dynamic parameter change curve, the improvement measures of tower structure are put forward, and the dynamic response of the structure before and after improvement is compared. The superiority of the improved structure is expounded, so as to provide reference basis for engineering application.

China implemented the first phase of its National Healthy Cities pilot program from 2016-20. Along with related urban health governmental initiatives, the program has helped put health on the agenda of local governments while raising public awareness. Healthy City actions taken at the municipal scale also prepared cities to deal with the COVID-19 pandemic. However, after intermittent trials spanning the past two decades, the Healthy Cities initiative in China has reached a crucial juncture. It risks becoming inconsequential given its overlap with other health promotion efforts, changing public health priorities in response to the pandemic, and the partial adoption of the Healthy Cities approach advanced by the World Health Organization (WHO). We recommend aligning the Healthy Cities initiative in China with strategic national and global level agendas such as Healthy China 2030 and the Sustainable Development Goals (SDGs) by providing an integrative governance framework to facilitate a coherent intersectoral program to systemically improve population health. Achieving this alignment will require leveraging the full spectrum of best practices in Healthy Cities actions and expanding assessment efforts.Tsinghua-Toyota Joint Research Fund "Healthy city systems for smart cities" program.

The toxic effects of lead on human health and the environment have long been a focus of research. To explore sources of lead in Guangzhou, China, we investigated atmospheric lead-containing particles (LCPs) during wintertime using a single particle aerosol mass spectrometer (SPAMS). Based on mass spectral features, LCPs were classified into eight major particle types, including Pb-Cl and Pb-Cl-Li (coal combustion and waste incineration), Pb-Cl-EC and Pb-Cl-OC (diesel trucks and coal combustion), Pb-Cl-Fe (iron and steel industry), Pb-Cl-AlSi (dust), Pb-Sec (secondary formation), and Pb-Cl-Zn (industrial process); these sources (in parentheses) were identified by comparing atmospheric LCP mass spectra with authentic Pb emission source mass spectra. Sampling periods with LCP number fractions (NFs) more than three times the average LCP NF (APF = 4.35%) and below the APF were defined as high LCP NF periods (HLFPs: H1, H3, and H5) and low LCP NF APF periods (LLFPs: L2 and L4), respectively. Diurnal patterns and high Pb-Sec content during LLFPs indicate that photochemical activity and heterogeneous reactions may have controlled Pb-Sec particle formation. The inverse Pb-Cl and Pb-Sec particle diurnal trends during LLFPs suggest the replacement of Cl by sulfate and nitrate. On average over the five periods, ~ 76% of the LCPs likely arose from coal combustion and/or waste incineration, which were dominant sources during all five periods, followed by diesel trucks during LLFPs and iron- and steel-related sources during HLFPs; HLFP LCPs arose mainly from primary emissions. These results can be used to more efficiently control Pb emission sources and prevent harm to human and environmental health from Pb toxicity.

Operation states of multiple solitons (MS), noise-like pulses (NLP), and a special pattern of MS coexist with NLP have been observed in a passively mode-locked erbium-doped fiber laser. By increasing the pump power or adjusting the polarization state of the cavity, the operation state from MS to NLP will go through three states: pure MS, MS & NLP, and pure NLP. The experiment results show that the state transition from pure MS to MS & NLP is mutational, while the state transition from MS & NLP to pure NLP is gradual. To our knowledge, this is the first time detailed exploration of the conversion process from MS to NLP operation in mode-locked fiber laser.

With the development of nuclear power and the depletion of uranium resources on land, extracting uranium from seawater has become a grand task. In particular, the synthesis of highly efficient and selective adsorbents becomes very important. Three copolymers (P(AO/C2VIM+Br−)-6, P(AO/C6VIM+Cl−)-3 and P(AO/C12VIM+Cl−)-2 were synthesized by radical polymerization, alkyl substitution and the amidoximation reaction of hydroxylamine. The copolymers were characterized by using FTIR, XPS, 1H NMR, and elemental analysis. The effects of different amount of imidazole cation and different length of branched chain on the adsorption were investigated by batch experiments, including solid-liquid ratio, contact time, pH, ionic strength, and coexisting ions. Meanwhile, the adsorption thermodynamics and kinetics of U(VI) on the copolymers were carried out. The results proved that the U(VI) adsorption by the copolymers strongly depended on ionic strength and pH, and fit well with pseudo–second-order model and Langmuir model and displayed endothermic, spontaneous process. Based on FTIR and XPS analysis, the possible binding mechanism involved uranyl with oxime O and amino nitrogen by bidentate coordination model or through bidentate coordination of oxime O, amino N and imidazole N. In addition, a little uranium might be adsorbed with positive charges by coulombic interaction, especially the adsorption of uranium on copolymer P(AO/C12VIM+Br−)-2. Finally, reuse performance of copolymers and adsorption of uranium in simulated seawater were studied comparatively. The results showed that P(AO/C2VIM+ Br−)-6 can be regarded as a good adsorbent for extracting uranium in simulating seawater.

Graph-based methods have shown their potentialities for saliency detection. In this paper, a graph-based framework is proposed for saliency detection, which incorporates perceptual cues into the framework and uses the background-excluded seeds to propagate saliency. Firstly, a graph is constructed by two perceptual cues, including proximity and similarity. Secondly, probable background nodes are generated by a novel background probability measure and used to pick out reliable seeds. Then a label propagation model is developed to diffuse saliency based on these reliable seeds. Lastly, another perceptual cue called rareness is integrated into a cost function to optimize the propagation result. Results on four datasets demonstrate that the proposed method achieves superior performance against fifteen state-of-the-art methods in terms of different evaluation metrics.

While wetlands contribute significantly to ecosystem services, their nature as a public good implies that the public sector, rather than the market, values their conservation, utilization, and trade-offs among various ecosystem services. Thus, the valuation of wetlands and their ecosystem services is important for policy makers. This study conducts a meta-analysis of valuation research on China’s wetlands based on 133 independent studies that involved 146 cases over the period 2000–2017. The study evaluates the weight of different factors in the existing valuation results, discusses the errors of benefit transfer, and applies the benefit transfer method to evaluate the ecosystem services of Yancheng wetland in Jiangsu province. The primary results are as follows. Wetland size influences the wetland service valuation results the most significantly. The value of all ecosystem services increases as wetland area increases with an average elasticity of 0.83. Factors such as economic and social development level, wetland type, research time, literature source, and valuation methods have impacts only on several individual service types. It is feasible to apply the meta-analysis results to benefit transfer. Compared with the per unit area value model, which is more stable in transfer errors, the wetland service value has better goodness of fit. Therefore,in conducting benefit transfer, the wetland service value models are suggested.

This paper aims to evaluate the cost of environmental degradation by adopting the conventional environmental economic methodology in China from 2004 to 2017 and summarize the change in both the causes and costs of China’s environmental degradation. Results from this study revealed the following: i. The environmental degradation cost in China increased from 511 billion yuan to 1,892 billion yuan from 2004 to 2017, and its share in the GDP decreased from 3.05% to 2.23%; ii. The environmental degradation cost growth rate was lower than the GDP growth rate. The environmental degradation cost growth rate decreased sharply, by dropping from 10% in 2014 to 2% in 2017. The environmental benefits of industrial transformation have emerged; iii. The provinces of Shandong, Hebei, Jiangsu, Henan, and Guangdong had the highest environmental degradation costs. The annual average growth rate of the environmental degradation costs in Jiangsu, Guangdong, and Zhejiang were lower than their growth rate of the GDP respectively; iv. Consideration of environmental degradation cost in decision-making could contribute to the high-quality development of China.

The feasibility of applying rapid and non-destructive analysis based on Visible/ Near-Infrared Spectroscopy (VIS/NIR spectrometer) in detecting Malus Asiatica Nakai’s firmness during different shelf lives was discussed in this manuscript. Based on the best preprocessing technique found for each method, calibration models established by Partial Least-Square (PLS), Principal Component Regression (PCR), and Least Squares-Support Vector Machine (LS-SVM) were compared. The optimal models for firmness of Malus Asiatica Nakai were obtained by PLS with SNV as the best pretreatment. On the 1st day of shelf life, the correlation coefficients of prediction (Rp) and the Root-Mean-Square Errors of Prediction (RMSEP) were 0.7999 and 0.7994, respectively. On the 4th day of shelf life, the indexes were 0.7494 and 0.5856. But with the extension of shelf life, weightlessness rate of Malus Asiatica Nakai was reduced, the mealiness phenomenon became serious, quality had dropped sharply, hence the research of Malus Asiatica Nakai became insignificant. Results showed that, the potential of non-destructive measure for predicting accepted fruit parameters enabled the determination of optimum harvest date and fruit quality in different shelf lives.