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Inconsistent measurements of city-size and a lack of time-series information on urban socioeconomic development have hindered determining whether China's city-size distribution (CD) follows a Pareto distribution according to multiple perspectives. This article has attempted to evaluate China's CD based on the defense meteorological satellite program- operational line-scan system (DMSP-OLS) nighttime light data in terms of socioeconomic size (SS) and spatial size (SC). First, city size was defined from the DMSP-OLS data. Then, whether China's CD followed a Pareto distribution was evaluated from different perspectives. The results show that China's CD from 1995 to 2015 presents a flat distribution trend; the flat distribution trend of the SC is more obvious than that of the SS; “borrowed size” has become an important reason for the flat trend of China's CD; and residential suburbanization, transportation cost reductions, local government policies, and land finances could effectively explain the CD differences in the flat trends between the SS and SC. This article offers an effective means for quantifying and comparing CD in long time series at a large scale (e.g., national scale or regional scale) and provides a scientific decision basis for governments to build a reasonable CD system in China.

In order to improve early osseointegration and long-term survival rate of implants, a multifunctional titanium surface that promotes osteogenesis and antibacterial properties is expected. Incorporation of bioactive trace elements such as magnesium ions was proved a promising method to improve osseointegration of titanium. Phytic acid has strong chelating ability with multivalent cations, which has been used in surface modification. Moreover, phytic acid was proved antibacterial potential. Herein, to improve the osteogenic and antibacterial properties, a phytic acid-magnesium (PA-Mg) layer was introduced on titanium using phytic acid as a cross-linker molecule. No obvious changes of the surface characterization were observed by scanning electron microscopy and atomic force microscopy. X-ray photoelectron spectroscopy confirmed that the PA-Mg layer covalently bond to the Ti surface, and the thickness of the PA-Mg layer was about 150 nm. Besides, improved hydrophilic and more protein adsorption were observed on Ti-PA-Mg. Notably, a relatively controlled magnesium release was also observed on Ti-PA-Mg. Human bone mesenchymal stem cells showed better adhesion, proliferation, and osteogenic differentiation on Ti-PA-Mg samples, indicating improved biocompatibility and osteoinductivity. Moreover, Ti-PA-Mg had better antibacterial properties against porphyromonas gingivalis than Ti. Overall, the PA-Mg layer on Ti surface improved the osteogenic and antibacterial properties, which may have promise for use in dental implantation.

Currently, whether the urban development in China satisfies Zipf&rsquo, s law across different scales is still unclear. Thus, this study attempted to explore whether China&rsquo, s urban development satisfies Zipf&rsquo, s law across different scales from the National Polar-Orbiting Partnership&rsquo, s Visible Infrared Imaging Radiometer Suite (NPP-VIIRS) nighttime light data. First, the NPP-VIIRS data were corrected. Then, based on the Zipf law model, the corrected NPP-VIIRS data were used to evaluate China&rsquo, s urban development at multiple scales. The results showed that the corrected NPP-VIIRS data could effectively reflect the state of urban development in China. Additionally, the Zipf index (q) values, which could express the degree of urban development, decreased from 2012 to 2018 overall in all provinces, prefectures, and counties. Since the value of q was relatively close to 1 with an R2 value &gt, 0.70, the development of the provinces and prefectures was close to the ideal Zipf&rsquo, s law state. In all counties, q &gt, 1 with an R2 value &gt, 0.70, which showed that the primate county had a relatively stronger monopoly capacity. When the value of q &lt, 1 with a continuous declination in the top 2000 counties, the top 250 prefectures, and the top 20 provinces in equilibrium, there was little difference in the scale of development at the multiscale level with an R2 &gt, 0.90. The results enriched our understanding of urban development in terms of Zipf&rsquo, s law and had valuable implications for relevant decision-makers and stakeholders.

Mo-based Tb 2 O 3 -Dy 2 O 3 composites used as neutron absorbers in nuclear power reactor were synthesized by powder metallurgy. The comparative studies of Mo-based Tb 2 O 3 and Mo-based Dy 2 O 3 composites were carried out to deeply understand the phase evolution and microstructure characteristics of Mo-based Tb 2 O 3 -Dy 2 O 3 composites. Ball milling induced terbium oxide and dysprosium oxide in the powder mixtures to be first fined, nano-crystallized, amorphized and finally dissolved into Mo matrix to form the supersaturated nanocrystalline solid solution that was driven by mechanical work, not by negative heat of mixing. Mo lattice parameter increased with increasing ball-milling time, opposite for Mo grain size. A phase transformation of Dy 2 O 3 crystal from cubic to monoclinic and then to amorphous was observed during ball milling. The microhardness of sintered bulks was first increased and then decreased with increasing sintering time. The maximum value was obtained at the bulks sintered for 8 h. The microhardness and bulk density were increased with increasing sintering temperature before 1600 °C. The mechanism of ball milling and sintering was also discussed.

There is no consensus on the effect of China’s rapid urban expansion on the fine particulate matter (PM2.5) emissions from fossil fuel combustion (PC). Previous studies usually focused on the environmental effect of urban expansion from a single mode (e.g., spatial expansion). However, studies that simultaneously considered and compared the effect from spatial and socioeconomic modes are still lacking. Thus, we combined multiple data sources (e.g., nighttime light data, urban land datasets, and PC) and econometric methods to evaluate the effect of urban expansion on PC within different regions from spatial and socioeconomic modes. The results show that China’s urban socioeconomic expansion (UE) and urban spatial expansion (US) increased from 68.50% and 11.81 × 10−4, respectively, in 1992 to 72.23% and 66.86 × 10−4, respectively in 2012. The UE is the Granger cause of the increased PC in China. Through variance decomposition analysis, we also found that the UE contributed much more to the PC in China than the US. When comparing the different regions, we recognized that the UE was the key factor in explaining the increase in the PC in the eastern and northeastern regions, and the US could effectively explain the changes in the PC in the central region. The study provides a novel perspective for quantifying the effect of urban intensive and extensive development on haze pollution.

For a better environment and sustainable development of China, it is indispensable to unravel how urban forms (UF) affect the fine particulate matter (PM2.5) concentration. However, research in this area have not been updated consider multiscale and spatial heterogeneities, thus providing insufficient or incomplete results and analyses. In this study, UF at different scales were extracted and calculated from remote sensing land-use/cover data, and panel data models were then applied to analyze the connections between UF and PM2.5 concentration at the city and provincial scales. Our comparison and evaluation results showed that the PM2.5 concentration could be affected by the UF designations, with the largest patch index (LPI) and landscape shape index (LSI) the most influential at the provincial and city scales, respectively. The number of patches (NP) has a strong negative influence (−0.033) on the PM2.5 concentration at the provincial scale, but it was not statistically significant at the city scale. No significant impact of urban compactness on the PM2.5 concentration was found at the city scale. In terms of the eastern and central provinces, LPI imposed a weighty positive influence on PM2.5 concentration, but it did not exert a significant effect in the western provinces. In the western cities, if the urban layout were either irregular or scattered, exposure to high PM2.5 pollution levels would increase. This study reveals distinct ties of the different UF and PM2.5 concentration at the various scales and helps to determine the reasonable UF in different locations, aimed at reducing the PM2.5 concentration.

Manual hand counting of parasites in fecal samples requires costly components and substantial expertise, limiting its use in resource-constrained settings and encouraging overuse of prophylactic medication. To address this issue, a cost-effective, automated parasite diagnostic system that does not require special sample preparation or a trained user was developed. It is composed of an inexpensive (~US$350), portable, robotic microscope that can scan over the size of an entire McMaster chamber (100 mm2 ) and capture high-resolution (~1 μm lateral resolution) bright field images without need for user intervention. Fecal samples prepared using the McMaster flotation method were imaged, with the imaging region comprising the entire McMaster chamber. These images are then automatically segmented and analyzed using a trained convolution neural network (CNN) to robustly separate eggs from background debris. Simple postprocessing of the CNN output yields both egg species and egg counts. The system was validated by comparing accuracy with hand-counts by a trained operator, with excellent performance. As a further demonstration of utility, the system was used to conveniently quantify drug response over time in a single animal, showing residual disease due to Anthelmintic resistance after 2 weeks.

Multivariate metal-organic frameworks with active Fe/Ni building blocks that are spatially arranged in an open structure are synthesized and explored for oxygen evolution reaction. The heterogeneity and porosity of this system prove to show synergy effect and give low onset overpotential at 170 mV. These MOFs are further fabricated into thin films over nickel foam by controlled electrochemical deposition to improve the surface conductivity and the overall stability. The Fe/Ni metal-organic framework film exhibits outstanding electrocatalytic activity with low overpotential of 270 mV at 10 mA cm(-2), small Tafel slope, high Faradaic efficiency, high turnover frequency, and great stability.

We first present a blockchain-based trusted cloud radio over optical fiber network architecture (BlockONet) with anonymous access identification for future 5G fronthaul. The feasibility and efficiency of the architecture are experimentally verified on our testbed.

Artificial photosynthesis requires efficient anodic electrode materials for water oxidation. Cobalt metal thin films are prepared through facile physical vapor deposition (PVD) on various nonconductive substrates, including regular and quartz glass, mica sheet, polyimide, and polyethylene terephthalate (PET). Subsequent surface electrochemical modification by cyclic voltammetry (CV) renders these films active for electrocatalytic water oxidation, reaching a current density of 10 mA cm-2 at a low overpotential of 330 mV in 1.0 m KOH solution. These electrodes are robust with unchanged activity throughout prolonged chronopotentiometry measurements. This work is thus significant to show that the combination of PVD and CV is very valuable and convenient to fabricate active electrodes on various nonconductive substrates, particularly with flexible polyimide and PET substrates. This efficient, safe and convenient method can potentially be expanded to many other electrochemical applications.