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In recent years, microplastics (MPs) as emerging carriers for environmental pollutants have attracted increasing worldwide attention. However, the adsorption of heavy metals on MPs, especially for biodegradable MPs, has been still poorly understood in estuarine environments. In this study, we investigated the aging of biodegradable and conventional MPs in the Pearl River Estuary after long-term exposure and their impacts on the adsorption of heavy metals from seawater. The results showed that the changes in surface characteristics were more prominent on biodegradable MPs than on conventional MPs after aging. Both biodegradable and conventional MPs could adsorb heavy metals, and their adsorption capacities fluctuated greatly on different MPs and different exposure times. The adsorption capacities of Cu, Pb, and As on biodegradable MPs were higher than those on conventional MPs, whereas Mn, Cr, and Co had lower adsorption on biodegradable MPs after 9–12 months by inductively coupled plasma-mass spectrometry (ICP-MS). The aging characteristics (CI, O/C, and X c) of MPs accounted for a contribution of 51.0% on heavy metal adsorption, while the environmental factors (temperature, salinity, pH, and heavy metal concentration) only contributed to 13.2%. Therefore, the present study can provide important evidence on the environmental behaviors and ecological risks of biodegradable and conventional MPs in estuarine systems. [Display omitted] • Adsorption of heavy metals on biodegradable MPs was first reported in the Pearl River Estuary. • The changes in the physicochemical property of biodegradable MPs were distinct. • Biodegradable MPs tend to particularly adsorb Cu, Pb, and As. • The aging properties of MPs had a strong relationship with heavy metal adsorption. [ABSTRACT FROM AUTHOR]

Abstract: This article first studied the nature of multiregional CGE models and reviewed relevant studies in such models. The article also constructed a static eight-region CGE model using an interregional input-output table for China. The model reflected the sizes of economies and differences in industrial structures across regions. More importantly, based on related empirical research, the model characterized the main economic relations across regions, such as interregional commodity flows, labor flows, and capital flows. Finally, some simulations were carried out to reveal the important effect that comes from the regional differences and linkages. The results shows the specifications of the regional differences and key linkages have significant influences on policy analysis. [ABSTRACT FROM AUTHOR]

• Microbial mats from the Jixian Group, North China were systemically investigated and three types of them were recognized. • Five kinds of sedimentary structure which were built by or related to microbial mat were recovered. • Bottleneck structures and bubble structures have been recovered and studied for the first time. Microbial mats were well established and widespread during the Proterozoic eon, playing a pivotal role in atmospheric oxygen content. In this study, microbial mats were systematically investigated from the 1600 Ma to 1400 Ma Jixian Group, North China. Three types of microbial mats were recognized, including Microbial Mat dominated by Filaments (MMF), Microbial Mat dominated by Coccoids (MMC), Microbial Mat dominated by Filaments and Coccoids (MMFC). These microbial mats were mainly built by Siphonophycus kestron , Siphonophycus solidum , Myxococcoides sp. and Coniunctiophycus majorinum. Due to in situ preservation, five sedimentary structures related to photosynthesis and oxygen release were discovered in these microbial mats. The alternating light-dark laminae and bottleneck structure may be caused by immediate mineralization and phototropism of filaments in a hypersaline environment. Bubble structure, fenestrae structure and hourglass structure probably were related to oxygen release, and their emergence fill the gap between oxygenic photosynthesis of microbial mat and atmospheric oxygen content in Proterozoic eon. [ABSTRACT FROM AUTHOR]

Margin trading in which investors purchase shares with money borrowed from brokers is blamed to be a major cause of the 2015 Chinese stock market crash. We propose a cascading failure model and examine how an increase in margin trading increases share price vulnerability. The model is based on a bipartite graph of investors and shares that includes four margin trading factors, (i) initial margin k , (ii) minimum maintenance r , (iii) volatility v , and (iv) diversity s . We use our model to simulate margin trading and observe how the share prices are affected by these four factors. The experimental results indicate that a stock market can be either vulnerable or stable. A stock market is vulnerable when an external shock can cause a cascading failure of its share prices. It is stable when its share prices are resilient to external shocks. Furthermore, we investigate how the cascading failure of share price is affected by these four factors, and find that by increasing v and r or decreasing k we increase the probability that the stock market will experience a phase transition from stable to vulnerable. It is also found that increasing s decreases resilience and increases systematic risk. These findings could be useful to regulators supervising margin trading activities. [ABSTRACT FROM AUTHOR]

A mass of traces of human activities show rich dynamic patterns. In this article, we comprehensively investigate the dynamic patterns of 50 thousands of researchers’ activities in Sciencenet , the largest multi-disciplinary academic community in China. Through statistical analyses, we found that (i) there exists a power-law scaling between the frequency of visits to an academic forum and the number of corresponding visitors, with the exponent being about 1.33; (ii) the expansion process of academic forums obeys the Heaps’ law, namely the number of distinct visited forums to the number of visits grows in a power-law form with exponent being about 0.54; (iii) the probability distributions of time intervals and the number of visits taken to revisit the same academic forum both follow power-laws, indicating the existence of memory effect in academic forum activities. On the basis of these empirical results, we propose a dynamic model that incorporates the exploration, preferential return with memory effect, which can well reproduce the observed scaling laws. [ABSTRACT FROM AUTHOR]

[Display omitted] Establishing a suitable tunnel boring machine (TBM) performance estimation model is benefit to the machine type selection, project scheduling and budgeting. Although various models have been developed to predict TBM performance, most of these models use a relatively small specific database, which is difficult to be applied to engineering practice. In this study, some equations for estimating TBM penetration rate (PR) applicable to different geological conditions are proposed. Firstly, a TBM construction performance database containing 159 tunnel sections is built according to four different tunnel projects originating from China, which covers rock mass properties, TBM specification parameters and performance information. By eliminating the effects of some TBM specification and operating parameters, a normalized energy index is proposed for assessing the rock mass boreability. On this basis, a series of statistical analysis, i.e. linear multiple regression (LMR) and non-linear multiple regression (NLMR) are used to develop some empirical equations for estimating the PR by employing rock mass properties and TBM specification parameters, and more than 84% of the PR can be accurately predicted. Finally, to further evaluate the prediction performance of these equations, they are compared and discussed with fifteen published typical models, and the results proved that the models developed in this study are more reasonable and reliable. It should be noted that the input parameters of these equations are readily available at the project planning stage, thus they are very simple and practical for designers and constructors. [ABSTRACT FROM AUTHOR]

The power output of photovoltaic (PV) systems is chiefly affected by climate and weather conditions. In that, PV farm requires accurate weather data, particularly, solar irradiance, in order to predict its power output as a means to improve solar energy utilization. Nevertheless, publicly available datasets which consist both power and weather data are exceptionally few. This may be a combined effect of data propriety and cumbersome collection procedure. And the rarity of such data greatly hinders the progress of solar PV research. Indeed, most solar energy meteorology applications, such as solar forecasting or PV performance evaluation, can benefit from multi-source high-quality datasets. In view of that, we release a PV power output dataset (PVOD), which contains metadata, numerical weather prediction data, and local measurements data from 10 PV systems located in China. In PVOD, a Python toolkit with basic functions for data access and preprocessing is provided. Additionally, a case study on PV power output estimation is depicted to demonstrate the potential usage of the dataset. • A publicly available dataset named photovoltaic power output dataset (PVOD). • A simple and extensible Python toolkit for PVOD. • A PV power output modeling example based on PVOD and Python toolkit. [ABSTRACT FROM AUTHOR]

Abstract: Landscape design of tunnel portals has been under intensive study in recent years. This paper summarizes the general development of highway tunnels and the main problems concerning highway tunnel entrances during this development phase in China. It then analyzes the significance of mountain highway tunnel landscape design in terms of preventing travel fatigue, visual adaptation, communicating and displaying culture, land marking, and environmental protection. Thirdly, it lays down the principles for landscape design, e.g. safety, failure prevention, physiological, anthropological, blending and economic principles. Lastly, it discusses the diversity of landscape designs in China, including types of tunnel portals, integration with local cultures (subdivided into ethnological culture, regional culture and historical culture), environmental protection awareness, lighting transitions in tunnel entrances, blending with the surrounding environment, symbolic and metaphorical skills in tunnel portal landscape design, and special decorations. The results suggest that landscape design of tunnel portals is a comprehensive artistic endeavor, involving local culture; bionomics; psychology; environment protection; lighting; structural techniques; new material implementation; and new technical arts. In conclusion, good landscape design requires intensive and collaborative interdisciplinary studies. [Copyright &y& Elsevier]

• A review to summarize the studies of chemical constituents, pharmacological activities and clinical studies et al. of Ixeris sonchifolia. • Traditional uses of IS, covering 19 TCM classics and 19 traditional uses containing IS, were presented in the form of Table. • All known chemical constituents isolated from IS and their chemical structures were enumerated in this review. • So far there are 11 methods used for analysis of IS, but the development of more advanced analysis methods is indispensable. • The assistant therapy action and curative effect evaluation of IS were discussed in detail. The assistant therapy action and curative effect evaluation of IS were discussed in detail. Ixeris sonchifolia (IS), principally its dried form, is widely used as traditional and folk medicines in some Asian countries, especially China. In this review, we summarized its traditional uses, chemical constituents, quality control measures, pharmacological activities, therapeutic evaluation, toxicity evaluation and clinical applications. 130 chemical constituents isolated from IS have been reported, including flavones, sesquiterpenes, triterpenes, phenylpropanoids, organic acids and others. They showed various pharmacological activities, such as protecting cardiocerebral vascular system, anticancer effect and antiviral etc. The quality control evaluation studies, clinical applications, other possible applications and suggestions for future research also were discussed. The aim of this review is to critically appraise the available literature and suggest directions for further development of IS to improve its medical value and use. [ABSTRACT FROM AUTHOR]

Land subsidence is the ground surface response to underground space development, utilization and evolution. Presently, land subsidence has developed into a global, comprehensive and interdisciplinary complex systems problem. More than half a century has passed since the discovery of subsidence in the Beijing Plain in the 1960s. In this study, we investigate the land subsidence in the Beijing Plain over the period of 2003–2015 using ENVISAT ASAR and RADARSAT-2 interferometric datasets and the small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technique. Furthermore, we introduced the data field model and index-based built-up index (IBI) to obtain the dynamic and static load information of the Beijing Plain. Then, based on a machine learning method, we selected the gradient lifting decision tree (GBDT) model to quantitatively analyze the contributions of groundwater level change, compressible deposit thickness and dynamic and static loads to land subsidence. The results showed that the maximum land subsidence rate was 122 and 141 mm/year in 2003–2010 and 2010–2015, respectively. Comparisons between the SBAS-InSAR results and leveling measurements showed that the minimum absolute error achieved was only 0.2 mm/year. We suggest that the groundwater exploitation in the third confined aquifer has greater impacts on land subsidence in the Beijing Plain than the other factors. The land subsidence likely occurred in compressible deposit thicknesses exceeding 90 m. Moreover, we found that the compressible thickness and groundwater level contributions to land subsidence exceeded 60%. Our results provide a scientific basis for the regulation and control of regional land subsidence. Unlabelled Image • The causes of land subsidence in Beijing Plain are complex. • The maximum land subsidence rate is 122 and 141 mm/year in 2003–2010 and 2010–2015. • The dynamic load by using a spatial data mining method of data field model. • The third confined aquifer groundwater has greater impacts on land subsidence. • Compressible thickness and groundwater contribution to land subsidence exceed 60%. [ABSTRACT FROM AUTHOR]

Lower Cambrian assemblages of phosphatic and chitinous tubular fossils of probable cnidarian affinities were recovered from the Yanjiahe, Shuijingtuo and Shipai formations in the Three Gorges area, South China. Terreneuvian Cambrorhytium cf. C . major co-occur with an unnamed taxon in the Yanjiahe Formation. They can be compared with specimens from the Ediacaran Miaohe Fauna in the Three Gorges area. The most abundant and diversified cnidarian assemblages, including Cambrorhytium gracilis n. sp., Cambrorhytium cf. major , Cambrorhytium minor , Sphenothallus songlinensis , Sphenothallus taijiangensis ?, Sphenothallus kozaki , ? Sphenothallus sp., ? Byronia sp., and ? Mackenzia sp. are reported from the overlying, Cambrian Stage 3–4, Shuijingtuo and Shipai formations. These new fossils show previously unknown evidence for cnidarian affinities, such as an attachment disk, clonal clusters and probable budding structures. These diversified assemblages of probable cnidarian fossils further fill major gaps in the Cambrian record of stem metazoans and document associated early evolutionary patterns. In addition, our discovery suggests that along with sponges, these tubular fossils represent another important component of benthic ecosystems that colonized often dysoxic, deep-settings during the Cambrian explosion. The observed increases of average body-size and biomineralization among these probable cnidarians are tentatively linked to oxygenation of deep oceanic settings and appearance of predatory pressure during the Ediacaran–Cambrian transition, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Discrete structural styles and mineral assemblages from auriferous quartz-ankerite-pyrite-arsenopyrite veins (Q2 and Q3) suggest superimposing gold mineralization at Tuanshanbei. • Comprehensive geological and H-O-Nd isotopic composition evidences are features that better adhere to metamorphic devolatilization models, indicating that the two-staged gold mineralization events both formed from metamorphic hydrothermal fluids originated from Cangxiyan Group metamorphic rocks. The Jiangnan Orogen is China's third largest gold province, and has undergone complex orogenic processes and tectonic overprinting, forming multistage magmatism, deformation, metamorphism, and gold mineralization. Our field studies indicate that the Tuanshanbei gold ores (central Jiangnan Orogen) have two generations of auriferous quartz-ankerite-pyrite-arsenopyrite veins (Q2 and Q3), with the latter containing abundant ankerite and base metal sulfides. Both Q2 and Q3 veins are younger than the emplacement of the Tuanshanbei granodiorite vein-ore host, and cut by post-ore diabase dikes. Q2 veins were likely associated with the Early Devonian near N-S-directed shortening, along sub-horizontal EW-/WNW-striking transpressive faults, whereas Q3 veins (hosting ∼ 70% of the total Au resource), were primarily hosted in the Early Triassic moderately-/steeply-dipping NW-striking tensional/transtensional faults and moderately-dipping NE-/NNE-striking transpressive faults, associated with NW-SE-directed shortening. Discrete structural styles and mineral assemblages from Q2 and Q3 suggest superimposing gold mineralization at Tuanshanbei. To determine the source(s) of the ore-forming aqueous-carbonic fluids, we conducted mineralogical and in-situ LA-(MC)-ICP-MS Nd-isotope analyses on two generations of hydrothermal monazite, and H-O isotope analyses on the quartz from Q2 and Q3 veins. The results suggest that the Tuanshanbei ore fluids have δD = −66.7 to −57.6‰ (Q2) and −66.8 to −66.2‰ (Q3), and calculated δ18O H2O = 4.5–9.7‰ (Q2) and 6.1–7.8‰ (Q3). The H-O isotopic data suggest a metamorphic and/or magmatic water source for the ore fluids. Hydrothermal monazite (coexists with native gold and auriferous sulfides) from Q2 and Q3 veins displays subtle heterogeneous BSE response along cracks and grain margin, suggesting alteration there. The 147Sm/144Nd and 143Nd/144Nd ratios of altered parts of Q2 and Q3 monazite grain are significantly perturbed via dissolution–recrystallization by the hydrothermal fluids, whereas their initial Nd isotope compositions seem to be less affected. The unaltered Q2 and Q3 monazite samples have similar initial εNd values (Q2: −8.07 to −7.36, Q3: −10.87 to −9.99) to the Neoproterozoic Cangxiyan Group greenschist–amphibolite-facies metamorphic rocks. Geological and structural evidence suggest both Q2 and Q3 ore-forming events were related to metamorphism, typical of orogenic gold deposits. We interpreted that various parts of the basement were metamorphosed (to near the greenschist-amphibolite-facies boundary) at different times, during which the gold-bearing metamorphic fluids produced migrated into the same structural conduits and deposited the ores there in two ore-forming episodes. [ABSTRACT FROM AUTHOR]

Interferometric synthetic aperture radar (InSAR) time-series analysis provides high spatial resolution and continuous temporal coverage for investigations of long-term ground displacement. Beijing, the capital city of China, has suffered from land subsidence since the 1950s, and extreme groundwater extraction has led to subsidence rates of > 100 mm/year. In this study, InSAR time-series analysis is performed on different data subsets to investigate the ground displacement at Capital International Airport, Beijing, between June 2003 and November 2013. The results show that the ground surface in the airport has deformed at different rates ranging from − 66.2 mm/year (sinking) to 8.2 mm/year (uplift) relative to the reference point. The projected vertical displacement rates agreed with measurements estimated from ground-leveling surveys, and the correlation coefficient of the fitting result is 0.96, with a standard deviation of 0.9 mm/year and a mean different of 2.0 mm/year. The runways and terminals have been affected by land subsidence to various degrees. Previous studies has indicated that long-term intense groundwater extraction is the main reason leading to land subsidence in this area. Other triggering factors, such as active faults, the quaternary compressible layers and urbanization, also have different degrees of contribution or impact on land subsidence in Beijing Plain. Furthermore, some interesting behaviors from groundwater (such as inter- and semi-annual variations) and subsidence, the relationship between them are also found in this study. [ABSTRACT FROM AUTHOR]

[Display omitted] • We provided more evidence on associations between legacy PFASs and PFAS alternatives and glucose-homeostasis. • We explored the joint associations of legacy PFASs and PFAS alternatives. • 6:2 Cl-PFESA contributed the most in the joint associations. • Sex-specific associations were observed. Epidemiological studies on the associations of legacy per- and polyfluoroalkyl substances (PFASs) and glucose homeostasis remain discordant. Understanding of PFAS alternatives is limited, and few studies have reported joint associations of PFASs and PFAS alternatives. To investigate associations of novel PFAS alternatives (chlorinated perfluoroalkyl ether sulfonic acids, Cl-PFESAs and perfluorobutanoic acid, PFBA) and two legacy PFASs (Perfluorooctanoic acid, PFOA and perfluorooctane sulfonate, PFOS) with glucose-homeostasis markers and explore joint associations of 13 legacy and alternative PFASs with the selected outcomes. We used cross-sectional data of 1,038 adults from the Isomers of C8 Health Project in China. Associations of PFASs and PFAS alternatives with glucose-homeostasis were explored in single-pollutant models using generalized linear models with natural cubic splines for PFASs. Bayesian Kernel Machine Regression (BKMR) models were applied to assess joint associations of exposures and outcomes. Sex-specific analyses were also conducted to evaluate effect modification. After adjusting for confounders, both legacy (PFOA, PFOS) and alternative (Cl-PFESAs and PFBA) PFASs were positively associated with glucose-homeostasis markers in single-pollutant models. For example, in the total study population, estimated changes with 95% confidence intervals (CI) of fasting glucose at the 95th percentile of 6:2Cl-PFESA and PFOS against the thresholds were 0.90 (95% CI: 0.59, 1.21) and 0.44 (95% CI: 0.26, 0.62). Positive joint associations were found in BKMR models with 6:2Cl-PFESA contributing most. Sex-specific associations existed in both single- and multi-pollutant models. Legacy and alternative PFASs were positively associated with glucose-homeostasis markers. 6:2Cl-PFESA was the primary contributor. Sex-specific associations were also identified. These results indicate that joint associations and effect modification should be considered in risk assessment. However, further studies are recommended to strengthen our findings and to elucidate the mechanisms of action of legacy and alternative PFASs. [ABSTRACT FROM AUTHOR]