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Mercury (Hg) pollution control has become an urgent need at global and national scales. This study, for the first time, comprehensively examines Hg flows in Mainland China and uncovers domestic and external causal drivers of China's Hg emissions/releases. Results show that China's Hg input reaches 2643 t in 2010. China discharges 1368 t of Hg to the environment (to air, 633 t; water, 84 t; and land, 651 t). Embedded Hg transfers across production sectors via waste/byproduct flows reduce Hg releases to land, but lead to secondary Hg emissions to air. Such revelations of embedded Hg transfers adjusts China's comprehensive Hg control that would otherwise only tackle primary emitters. Domestic consumption causes 67% of China's Hg emissions/releases, and external consumption induces the remaining 33%. Besides traditional production-side Hg control measures, demand-side measures and international joint efforts are required to effectively combat Hg pollution. Uncovering embedded and embodied Hg flows within the global economy can assist a paradigm shift necessary to make real progress in global Hg control and the implementation of the Minamata Convention on Mercury.

MicroRNAs (miRNAs) are short non-coding RNAs that are involved in the epigenetic regulation of cellular processes. To identify more miRNAs which are involved in the macrophage inflammatory response to lipopolysaccharide (LPS) stimulation and dissect the mechanisms more clearly, microRNA profiling of LPS-treated RAW264.7 macrophage cells was performed by initial high-throughput array-based screen and further real-time RT-PCR validation; bioinformatics approaches were used to analyze the target genes of the differentially expressed miRNAs. Compared to the untreated control, two microRNAs (miR-146a and miR-155) with more than twofold higher expression and two microRNAs (miR-27a* and miR-532-5p) with twofold lower expression were detected by array-based screen, which can be validated by qRT-PCR, and more than 1,000 candidate target genes were detected by at least of one of four different algorithms (TargetScan, PicTar, miRDB, and microRNA.org); with gene ontology classification, we were able to correlate the upregulation and downregulation of miRNA to the differential expression of inflammation-related candidate target gene during LPS-induced inflammation. Our findings may provide the basic information for the precise roles of miRNAs in the macrophage inflammatory response to LPS stimulation in the future.

Abstract. Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg 0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 • C to below 300 • C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg 0 to gaseous divalent mercury (Hg 2+ ), with a portion of Hg 2+ adsorbed onto fly ash to form particulate-bound mercury (Hg p ). Halogen is the primary oxidizer for Hg 0 in flue gases, and active components (e.g., TiO 2 , Fe 2 O 3 , etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34-85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hg p , and wet flue gas desulfurization system (WFGD) captures 60-95 % of Hg 2+ . In non-ferrous metal smelters, most Hg 0 is converted to Hg 2+ and removed in acid plants (APs). For cement clinker production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hg p accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg 0 fraction (66-82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg 2+ fraction (29-90 %) from non-ferrous metal smelting, cement and iron and/or steel production. The higher Hg 2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases.

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Multi-doped carbon dots (C-dots) were synthesized using a facile one-pot solvothermal method, and the C-dots can be used as a ratiometric pH probe directly without integrating with other dyes, which was demonstrated by monitoring the proton-producing enzyme catalytic reactions.

Fabrication of nanostructures with great complexity and regularity is a topic of intense current interest because of their importance both in fundamental theories and applications. Here we report an interesting finding of the formation of ordered polymeric double helices with precise structures and high stability. These uniform double helices are hierarchically self-assembling results of undulated multicompartment cylinders which formed from primary amphiphilic mixed-shell nanoparticles. Diblock copolymers of P2VN-b-PAA (poly(vinylnaphthalene)-block-poly(acrylic acid) and PEO-b-PAA (poly(ethylene oxide)-block-poly(acrylic acid)) were noncovalently/electrostatically cross-linked into amphiphilic PEO/P2VN-shelled nanoparticles by 1,6-hexyldiamine in a common solvent DMF. When the common solvent changed into selective ones (water), undulated cylinders were facilely obtained due to their hydrophobic interparticles interactions. After a certain time aging, these undulated cylinders self-organized into finally thermodynamic-stable double helices with complex but regular superstructures. The conditions and processes of assembling were carefully examined through extensive experiments.

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