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Projections of global rice yields account for climate change. They do not, however, consider the coupled stresses of impending climate change and arsenic in paddy soils. Here, we show in a greenhouse study that future conditions cause a greater proportion of pore-water arsenite, the more toxic form of arsenic, in the rhizosphere of Californian Oryza sativa L. variety M206, grown on Californian paddy soil. As a result, grain yields decrease by 39% compared to yields at today’s arsenic soil concentrations. In addition, future climatic conditions cause a nearly twofold increase of grain inorganic arsenic concentrations. Our findings indicate that climate-induced changes in soil arsenic behaviour and plant response will lead to currently unforeseen losses in rice grain productivity and quality. Pursuing rice varieties and crop management practices that alleviate the coupled stresses of soil arsenic and change in climatic factors are needed to overcome the currently impending food crisis.

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Carbon nanomaterials have proven their wide applicability in molecular separation and water purification techniques. Here, an unzipped carbon nanotubes (CNT) embedded graphene oxide (GO) membrane (uCNTm) is reported. The multiwalled CNTs were longitudinally cut into multilayer graphene oxide nanoribbons by a modified Hummer method. To investigate the varying effects of different bandwidths of unzipped CNTs on their properties, four uCNTms were prepared by a vacuum-assisted filtration process. Unzipped-CNTs with different bandwidths were made by unzipping multiwalled CNTs with outer diameters of 0–10, 10–20, 20–30, and 30–50 nm and named uCNTm-1, uCNTm-2, uCNTm-3, and uCNTm-4, respectively. The uCNTms exhibited good stability in different pH solutions, and the water permeability of the composite membranes showed an increasing trend with the increase of the inserted uCNTm’s bandwidth up to 107 L·m–2·h–1·bar–1, which was more than 10 times greater than that of pure GO membranes. The composite membranes showed decent dye screening performance with the rejection rate of methylene blue and rhodamine B both greater than 99%.

Purpose The purpose of this paper is to study the participation behaviors in the context of crowdsourcing projects from the perspective of gamification. Design/methodology/approach This paper first proposed a model to depict the effect of four categories of game elements on three types of motivation based upon several motivation theories, which may, in turn, influence user participation. Then, 5 × 2 between-subject Web experiments were designed for collecting data and validating this model. Findings Game elements which provide participants with rewards and recognitions or remind participants of the completion progress of their tasks may positively influence the extrinsic motivation, whereas game elements which can help create a fantasy scene may strengthen intrinsic motivation. Besides, recognition-kind and progress-kind game elements may trigger the internalization of extrinsic motivation. In addition, when a task is of high complexity, the effects from game elements on extrinsic motivation and intrinsic motivation will be less prominent, whereas the internalization of extrinsic motivation may benefit from the increase of task complexity. Originality/value This study may uncover the motivation mechanism of several different kinds of game elements, which may help to find which game elements are more effective in enhancing engagement and participation in crowdsourcing projects. Besides, as task complexity is used as a moderator, one may be able to identify whether task complexity is able to influence the effects from game elements on motivations. Last, but not the least, this study will indicate the interrelationship between game elements, individual motivation and user participation, which can be adapted by other scholars.

PurposeUnderstanding health experts' online free knowledge contribution behavior is vital for promoting health knowledge and improving health literacy. This study focuses on the spillover effects of different monetary incentive levels on health experts' free knowledge contribution behavior.Design/methodology/approachIn 2016, Zhihu Live and Zhi Hu were launched as two types of paid knowledge products on Zhihu.com, a hybrid knowledge exchange platform. Focusing on the policy impact of launching Zhihu Live and Zhi Hu, this study uses the difference-in-differences model to analyze the heterogeneous spillover effects of high-yield and low-yield monetary incentives on health experts' free knowledge contribution behavior.FindingsIn the short term, the high-yield monetary incentive has positive spillover effects on the quantity and quality of free knowledge contribution while the low-yield monetary incentive generates opposite effects. In the long term, the effects of the high-yield monetary incentive remain significantly positive. The effect of the low-yield monetary incentive on the quantity of free knowledge contribution remains significantly negative, but its effect on the quality of free knowledge contribution is not significant.Originality/valueThis study combines theories of reciprocity and resource limitation to study the spillover effects of different monetary incentive levels on health experts' online behavior. The short-term and long-term effects of different monetary incentive levels on health experts' online behavior are also explored.

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Purpose-Due to the increasing demand for public services, as a new form of public governance, e-participation has emerged. Scholars from various disciplines have published plenty of research results on e-participation. This paper aims to reveal the research status frontiers directly by mapping knowledge domains. Design/methodology/approach-The authors take 1,322 articles on e-participation published in Web of Science from 2001 to 2017 as research object. They then run the information visualization software CiteSpace to drill deeper into the literature data. Findings-The study found that e-participation research has the obvious interdisciplinary feature; the author and institution cooperation networks with less internal cooperation are relatively sparse; the USA ranks first in the field of e-participation research, followed by the UK, with the other countries lagged behind; and e-participation through social media is gradually becoming the new research focus. Originality/value-Based on the objective data and information visualization technology, the research intuitively reveals the research status and development trend of e-participation.