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Plastic debris (including macro-plastics, microplastics (MPs), and nanoplastics), defined as an emerging contaminant, has been proven to significantly affect soil ecosystem functioning. Accordingly, there is an urgent need to robustly quantify the pollution situation and potential sources of plastics in soils. China as the leading producer and user of agricultural plastics is analyzed as a typical case study to highlight the current situation of farmland macro-plastics and MPs. Our study summarized information on the occurrence and abundance of macro-plastics and MPs in Chinese farmland soils for the first time based on 163 publications with 728 sample sites. The results showed that the average concentration of macro-plastics, and the abundance of MPs in Chinese farmlands were 103 kg ha−1 and 4537 items kg−1 (dry soil), respectively. In addition, this study synthesized the latest scientific evidence on sources of macro-plastics and MPs in farmland soils. Agricultural plastic films and organic wastes are the most reported sources, indicating that they contribute significantly to plastic debris in agricultural soils. Furthermore, the modeling methods for quantifying macro-plastics and MPs in soils and estimating the stock and flow of plastic materials within agricultural systems were also summarized. [ABSTRACT FROM AUTHOR]

Plant biomass is a kind of renewable, abundant, eco-friendly, and clean natural resource. Recent increase in industrial demand, coupled with development and utilization of biocatalysts for utilization and production of high value-added products from plant biomass have attracted numerous research interest. The ester bond, between plant cell wall polysaccharides and ferulic acid (FA), can be hydrolysed by feruloyl esterases (FAE), thereby destroying compactness of lignocellulosic materials, which is beneficial during utilization of biomass resources. This is this research focus. In this article, we reviewed classification, characteristics, and application of FAE from different species, then highlighted the synergistic effect of FAE action with other enzymes. The findings are considered to provide insights into role of FAE in functional research, biochemical properties, and industrial application, especially with focus on processing of lignocellulosic biomass, harnessing hydroxycinnamate from agricultural by-products, and production of biofuels among other industrial uses. [ABSTRACT FROM AUTHOR]

Road network models form the foundation of road network analyses, route planning, navigation and traffic predictions. However, existing models cannot effectively represent the dynamic topological relationships that exist among lanes due to the effects of time-dependent traffic control measures. To address this problem, we propose a time-dependent road network model (TRNM) to represent these topological relationships, and present its construction method based on a traditional carriageway network model. We constructed two TRNMs in Changzhou and Shanghai and then conducted path-planning experiments to verify the effectiveness of the models. Our results showed that TRNMs could be constructed readily from traditional road networks without introducing large volumes of data, while effectively representing the time-dependent topological relationships among lanes. It is particularly beneficial to path planning, as it not only provides valid and shorter paths but also lane-level navigation information. Time-dependent road network models mirror real-world road networks and can represent more time-dependent traffic controls, such as non-periodic changes at different frequencies. The TRNM developed here can provide support for applications based on road network models, as well as a useful reference for the geographic information system (GIS) and complex networks. [ABSTRACT FROM AUTHOR]

We apply integrated parameter and tolerance design (IPTD) to optimize the nominal values and tolerances of 10 geometric design variables of a centrifugal compressor based on a computational fluid dynamics simulator. The compressor quality is quantified by the conformance probabilities of three performance measures (PMs) and optimizing the simulator directly is time-consuming. Gaussian process (GP) emulators are constructed to predict the PMs. A conservative conformance probability estimator penalized by its standard deviation and an efficient method to compute it are developed to facilitate optimization. Eight tolerances are loosened and two are tightened. Design variable effects on quality are better understood. [ABSTRACT FROM AUTHOR]

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Surface water is the main source of water for human life and production. The quality of water affects living conditions and the overall health of people. Ecological protection and restoration engineering technology, combining ecological revetment and an ecological floating bed, is applied to a selected shallow beach experimentation area of a reservoir water source area in Northeast China. According to local conditions, the ecological revetment plants were identified as Goosegrass, sedges, and water grasses, and other local species of Polygonum hydropiper bagen, reeds, and bulrushes were identified as ecological floating bed plants. Regular monitoring of water quality in the experimentation area and a control area showed that the ecological protection and restoration technology can effectively reduce the concentrations of BOD5 (five day biochemical oxygen demand), COD (chemical oxygen demand), TN, NH3-N, NO3−-N, TP, TDP, Mn, Zn, Fe, Pb, total coliforms, and other indicators of surface water in the experimentation area. The BOD5, COD, Max TN, NH3-N, NO3−-N, TP, and TDP reduction rates were 84.76%, 57.14%, 86.76%, 83.78%, 89.26%, 94.02%, and 95.89%, respectively, with the implementation of water pollution prevention and the purifying shoal. [ABSTRACT FROM AUTHOR]

The article analyzes whether China's Belt and Road Initiative (BRI) is a geopolitical strategy. Topics discussed are responsibility of China in reviving the ancient Silk Road and goal of BRI to promote inclusive development towards globalization, concept of Community of Shared Future as manifestation of Chinese Harmonious and Syncretic Culture that aims for geoeconomy and geocivilization, and misperceptions about the BRI.

This study aims to reveal the role of nitric oxide (NO) in substituting nitrite with lactic acid bacteria. Three lactic acid bacterial strains (L. fermentum JCM1173, L. fermentum IFO3956, Weissella cibaria X31) with nitrite substitution ability were inoculated into fermented sausages, respectively. Results indicated that the ratio of nitrosomyoglobin (NO-Mb) to total pigments was positively correlated with the substitution ability of the strain. UV-visible and resonance Raman spectroscopy suggested the NO-Mb was five-coordinated. In addition, the intracellular NO detected by fluorescent DAF-FM probe showed that W. cibaria X31 had the strongest NO-producing ability. Inhibitory experiments showed that both nitrate reductase and nitric oxide synthase-like protein participated in the NO production. These results indicated the vital role NO played in the substitution through the formation of NO-Mb and demonstrated the sources of NO in lactic acid bacteria preliminarily. [ABSTRACT FROM AUTHOR]

Surveillance cameras are widely deployed to monitor the geographical environment, traffic condition, public security, so on. Optimal deployment of surveillance cameras is an effective way to promote their validity and utilization. Because of the ignorance of geographic environment in major existing researches, a new optimization method which considers the constraining relationships between cameras and geographic environment is proposed. Firstly, coverage models for single camera and camera network which consider the occlusions in geographic environment are discussed. Secondly, the objective of optimization is put forward, which is to employ the minimum cameras to monitor the specific areas. Thirdly, to achieve the objective, the heuristic search algorithm is introduced. The deployable camera pose and location, and target area are discretized to promote the efficiency. Consequently, the deployment optimization problem is abstracted into a combinatorial optimization problem. Then optimization model including the graph structure, cost function and heuristic function for the algorithm is built to meet the requirement of the heuristic search algorithm, and its correctness is also strictly proofed. Finally, experiment in real city area with occlusions (such as building) validates the usability of our method. The sampling steps of camera pose and location and the split size of target area for discrete process are two important factors to influence the degree of accuracy and efficiency. The results obtained by our method can provide decision support for optimal camera deployment in real geographic environment, as well as provide reference for other environmental monitoring sensor deployment optimization tasks. [ABSTRACT FROM PUBLISHER]

Promoting public transit is a well-recognized policy for sustainable urban transport development. Transit demand analysis proves to be a challenging task in fast growing cities, partially due to the lack of reliable data and applicable techniques for rapidly changing urban contexts. This paper presents an effort to meet the challenge by developing a framework to estimate peak-hour boarding at light-rail transit (LRT) stations. The core part of the framework is an accessibility-weighted ridership model that multiplies potential demand by integral LRT accessibility. Potential demand around LRT stations is generated by using a distance-decay function. The integral LRT accessibility is a route-level factor that indicates the degree of attractiveness to LRT travel for stations in an LRT corridor. A case study in Wuhan, China, shows that the proposed method produces results useful for improving transit demand analysis. [ABSTRACT FROM AUTHOR]

Urban water sources are the major source of water resources for urban life, and its water quality affects the daily life and health of the local people. However, there were some reports on the poor water quality status of water sources in the past. In the present study, by applying fuzzy synthetic evaluation, the water quality was studied from a total of 24 water samples from a reservoir-type water source in the northeastern region of China. Health risks of eight trace elements in source water were assessed using health risk assessment model and Monte Carlo simulation, and source apportionment of eight trace elements in source water were also analyzed. The results indicated that the water quality of the source water was acceptable for category I surface water, while the concentrations of total phosphorus (TP) and manganese (Mn) were higher than the permissible level. The noncarcinogenic risks due to eight trace elements exposure were As > Mn > Pb > Cd ≈ Cr > Se > Zn > Cu and carcinogenic risk of Arsenic (As) was 3E−05 with a maximum probability. Furthermore, statistical analyses, such as correlation analysis, principal component analysis (PCA) and cluster analysis (CA) showed that the trace metals in the water source have a certain degree of anthropogenic contributions, especially Mn. Overall, both the contents of TP and Mn and the health risk of As require some attention of the relevant department, and further protected measures should be taken in the source water. [ABSTRACT FROM PUBLISHER]

A novel anticoagulant protein (E-II-1) was separated and purified fromHypomesus olidus, a unique freshwater fish in northern China. E-II-1 had a molecular mass of approximately 40 kDa with no subunits. The high content of hydrophobic amino acids and negatively charged amino acids in E-II-1 demonstrated that the amino acid compositions might contribute to the anticoagulant activity. E-II-1 containedα-helices 16.75%,β-sheets 42.67%,β-turn 25.58% and random coil 15.00%.In vitroblood coagulation time assay, E-II-1 significantly prolonged the activated partial thrombin time in a dose-dependent manner. Results indicated that E-II-1 acted as anticoagulants through the endogenous pathway with an inhibition of FXa. The specific activity of E-II-1 was 103.50 U/mg at a concentration of 1.00 mg/mL. Therefore, E-II-1 might be one of the promising anticoagulants originated from natural food sources with more safety and less side effects. [ABSTRACT FROM PUBLISHER]

Two novel triblock copolymers poly(hydroxypropyl acrylate)-b-poly (methyl methacrylate)-b-poly(N,N-dimethylaminoethyl methacrylate) and poly(hydroxypropyl acrylate)-b-poly(methyl methacrylate)-b-poly(acrylic acid) were successfully synthesized. In acetone media, using the electrostatic interactions betweenN,N-dimethylaminoethyl methacrylate and acrylic acid units, they could form spherically shaped multilayer micelles with pH-responsive, and have a mean diameter around 110 nm. The critical micelle concentration of it was determined to be 2.42 mg/L. In vitro release experiments, the folic acid-loaded micelles exhibited sustained release behavior and the drug release rate was affected by the pH value of release media. These results indicate that the multilayer micelles may serve as a novel intelligent drug delivery system. [ABSTRACT FROM AUTHOR]

Through unflooded mulching in field plots and 15nitrogen microplot tracer experiments, nitrogen (N) uptake of rice and N utilization have been studied compared with normal irrigation cultivation. The results showed that N uptake of unflooded rice and N derived from fertilizer (NDFF) of root, stem, and grain under mulching cultivation were lower than that under cultivation without mulching. However, the NDFF of rice under unflooded cultivation was higher than that under normal irrigation cultivation. The N utilization has been greatly enhanced under unflooded cultivation without mulching and unflooded plastic film cultivation with mulching as compared with normal irrigation. At the same time, there was no significant difference on the N uptake of unflooded rice among different ways of mulching cultivations. During the growth period of rice, no prominent differences were found in the soil residue, recovery, and N losses of fertilizer except the N uptake of rice between unflooded mulching and normal irrigation. The yield of rice under film mulching and straw mulching cultivation was higher than that of cultivation without mulching in the condition of unflooded cultivation, whereas the yield of rice under irrigation cultivation was higher than that under unflooded cultivation. [ABSTRACT FROM AUTHOR]

The syntheses of three hexadecaimino nanocapsules 4b-d via the trifluoroacetic acid-catalysed condensation of four equivalents of a tetraformylcavitand 2 with eight equivalents of 1,4-phenylenediamine 3b, benzidine 3c or 4,4'-ethylenedianiline 3d, respectively, are reported. These nanocapsules are shaped like a tetragonal tetrahedron and have solvodynamic diameters of 2.5-3 nm, which were estimated from their diffusion constants. The smallest of these tetragonal tetrahedra 4b, which has a cavity volume of 1250 Å3, forms 1:1 and 2:1 complexes with R4N+Br- salts (R = n-pentyl, n-hexyl, n-heptyl) in organic solvents. Complexation-induced shifts and the slow exchange rates between the free and complexed guests are consistent with the guest being fully encapsulated inside the nanocapsule. [image omitted] [ABSTRACT FROM AUTHOR]

The objective of this research is to study the relationship between terrain complexity and terrain analysis results from grid‐based digital elevation models (DEMs). The impact of terrain complexity represented by terrain steepness and orientation on derived parameters such as slope and aspect has been analysed. Experiments have been conducted to quantify the uncertainties created by digital terrain analysis algorithms. The test results show that (a) the RMSE of derived slope and aspect is negatively correlated with slope steepness; (b) the RMSE of derived aspect is more sensitive to terrain complexity than that of derived slope; and (c) the uncertainties in derived slope and aspect tend to be found in flatter areas, and decrease with increasing terrain complexity. The study shows that although primary surface parameters can be well defined mathematically, the implementation of those mathematical models in a GIS environment may generate considerable uncertainties related to terrain complexity. In general, when terrain is rugged with steep slopes, the uncertainty of derived parameters is quite minimal. While in flatter areas, the DEM‐based derivatives, particularly the aspect, may contain a great amount of uncertainty, causing significant limitation in applying the analytical results. [ABSTRACT FROM AUTHOR]

Understanding the effects on nitrogen (N) transformations and supply to crops of dicyandiamide (DCD) and the various plant residues applied with N fertilizer in China is vital for maximizing crop yields and minimizing environmental pollution. Nitrogen transformations were measured in a Chinese Aquic Cambisol following the application of urea (U), or U with DCD, wheat straw (WS), alfalfa straw (AS), and poultry manure (PM) by aerobic incubation in the laboratory. Nitrification was rapid in the 7 days after U or U with WS, AS, and PM were applied; almost all the applied N from U was nitrified by the 14th day, but only 20% by the 35th day, where DCD was applied with the U. The NH4-N concentrations in the soil with U + DCD was always much higher than those in the other treatments. The results thus showed that DCD significantly inhibited nitrification on this soil. The high C:N ratio of WS significantly decreased the amount of Nmin (NH4-N plus NO3-N) in soil, while the low C:N ratio of AS and PM significantly increased Nmin compared with the U treatment. The content of Norg (organic N extracted by 0.01 M CaCl2 solution) in the soil was much lower than that of Nmin and was not significantly different between the treatments, except for the U + DCD treatment, where it measured as DCD. The N recovery and loss rate after 35 days' incubation, as measured by 15N tracer, was not significantly different in the U, U + WS, U + AS, and U + PM treatments, but recovery was significantly higher and loss correspondingly smaller when DCD was applied. With DCD, the N fertilizer was mostly fixed in soil after 35 days but without DCD was present as NO3-N. For effective use of fertilizers in the North China Plain, an understanding of the effects of applying inhibitors such as DCD and plant residues is needed. [ABSTRACT FROM AUTHOR]

This paper reports an investigation on the accuracy of grid-based routing algorithms used in hydrological models. A quantitative methodology has been developed for objective and data-independent assessment of errors generated from the algorithms that extract hydrological parameters from gridded DEM. The generic approach is to use artificial surfaces that can be described by a mathematical model, thus the 'true' output value can be pre-determined to avoid uncertainty caused by uncontrollable data errors. Four mathematical surfaces based on an ellipsoid (representing convex slopes), an inverse ellipsoid (representing concave slopes), saddle and plane were generated and the theoretical 'true' value of the Specific Catchment Area (SCA) at any given point on the surfaces could be computed using mathematical inference. Based on these models, tests were made on a number of algorithms for SCA computation. The actual output values from these algorithms on the convex, concave, saddle and plane surfaces were compared with the theoretical 'true' values, and the errors were then analysed statistically. The strengths and weaknesses of the selected algorithms are also discussed. [ABSTRACT FROM AUTHOR]