453 research outputs found

    Air Pollution Control Policies in China: A Retrospective and Prospects

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    With China’s significant role on pollution emissions and related health damage, deep and up-to-date understanding of China’s air pollution policies is of worldwide relevance. Based on scientific evidence for the evolution of air pollution and the institutional background of environmental governance in China, we examine the development of air pollution control policies from the 1980s and onwards. We show that: (1) The early policies, until 2005, were ineffective at reducing emissions; (2) During 2006–2012, new instruments which interact with political incentives were introduced in the 11th Five-Year Plan, and the national goal of reducing total sulfur dioxide (SO2) emissions by 10% was achieved. However, regional compound air pollution problems dominated by fine particulate matter (PM2.5) and ground level ozone (O3) emerged and worsened; (3) After the winter-long PM2.5 episode in eastern China in 2013, air pollution control policies have been experiencing significant changes on multiple fronts. In this work we analyze the different policy changes, the drivers of changes and key factors influencing the effectiveness of policies in these three stages. Lessons derived from the policy evolution have implications for future studies, as well as further reforming the management scheme towards air quality and health risk oriented direction

    Air Pollution Control Policies in China: A Retrospective and Prospects

    Get PDF
    With China’s significant role on pollution emissions and related health damage, deep and up-to-date understanding of China’s air pollution policies is of worldwide relevance. Based on scientific evidence for the evolution of air pollution and the institutional background of environmental governance in China, we examine the development of air pollution control policies from the 1980s and onwards. We show that: (1) The early policies, until 2005, were ineffective at reducing emissions; (2) During 2006–2012, new instruments which interact with political incentives were introduced in the 11th Five-Year Plan, and the national goal of reducing total sulfur dioxide (SO2) emissions by 10% was achieved. However, regional compound air pollution problems dominated by fine particulate matter (PM2.5) and ground level ozone (O3) emerged and worsened; (3) After the winter-long PM2.5 episode in eastern China in 2013, air pollution control policies have been experiencing significant changes on multiple fronts. In this work we analyze the different policy changes, the drivers of changes and key factors influencing the effectiveness of policies in these three stages. Lessons derived from the policy evolution have implications for future studies, as well as further reforming the management scheme towards air quality and health risk oriented direction

    Continuous variable entanglement enhancement and manipulation by a sub-threshold type-II optical parametric amplifier

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    We experimentally demonstrate that the quantum entanglement between amplitude and phase quadratures of optical modes produced from a non-degenerate optical parametric amplifier (NOPA) can be enhanced and manipulated phase-sensitively by means of another NOPA. When both NOPAs operate at de-amplification, the entanglement degree is increased at the cavity resonance of the second NOPA. When the first NOPA operates at de-amplification and the second one at amplification, the spectral features of the correlation variances are significantly changed. The experimental results are in good agreement with the theoretical expectation

    Genome-wide analysis of mono-, di- and trimethylation of histone H3 lysine 4 in Arabidopsis thaliana

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    Analysis of the genome-wide distribution patterns of histone H3 lysine4 methylation in Arabidopsis thaliana seedlings shows that it has widespread roles in regulating gene expression

    Effective Techniques for Working with the Tongue Twister in the Elementary Level of Training Russian as a Foreign Language

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    The selection of material for teaching phonetics is a topical problem in the practice of teaching Russian as a foreign language. In this article the tongue twister, as the material for the development of phonetic skills at the elementary level of teaching Russian to foreigners, will be discussed. It is proposed to work only with one tongue twister during daily phonetic exercises. It is also important to organize the work with different types of activities. This paper presents a set of tasks (about 20 exercises) and builds on the principle "from syllable to phrases and sentences", which can be done in a short time. In addition, this paper describes the tasks employing tongue twisters by studying grammatical material. These methods can be called effective because they develop different skills, introduce diversity, dynamism in the learning process and help to combat fatigue

    Genome-Wide Association of Histone H3 Lysine Nine Methylation with CHG DNA Methylation in Arabidopsis thaliana

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    Methylation of histone H3 lysine 9 (H3K9) is a hallmark of transcriptional silencing in many organisms. In Arabidopsis thaliana, dimethylation of H3K9 (H3K9m2) is important in the silencing of transposons and in the control of DNA methylation. We constructed a high-resolution genome-wide map of H3K9m2 methylation by using chromatin immunoprecipitation coupled with whole genome Roche Nimblegen microarrays (ChIP-chip). We observed a very high coincidence between H3K9m2 and CHG methylation (where H is either A,T or C) throughout the genome. The coding regions of genes that are associated exclusively with methylation in a CG context did not contain H3K9m2. In addition, we observed two distinct patterns of H3K9m2. Transposons and other repeat elements present in the euchromatic arms contained small islands of H3K9m2 present at relatively low levels. In contrast, pericentromeric/centromeric regions of Arabidopsis chromosomes contained long, rarely interrupted blocks of H3K9m2 present at much higher average levels than seen in the chromosome arms. These results suggest a complex interplay between H3K9m2 and different types of DNA methylation and suggest that distinct mechanisms control H3K9m2 in different compartments of the genome
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