Surface ozone (O 3 ) pollution showed a continuous increasing trend during the recent decades in China, posing an increasing threat to food security. A wide range of yield reductions have been reported and thus more s...
Surface ozone (O 3 ) pollution showed a continuous increasing trend during the recent decades in China, posing an increasing threat to food security. A wide range of yield reductions have been reported and thus more studies are needed to narrow down the uncertainty resulting from spatiotemporal accuracy of O 3 metrics and extrapolation methods. Based on a high spatial resolution (0.1°) hourly surface O 3 data, here we analyzed the spatiotemporal O 3 pollution patterns and impacts on yield, production and economic losses for wheat, rice, and maize in China during 2005–2020. The accumulated O 3 exposure over a threshold of 40 ppb (AOT40) increased by 10 % during 2005–2019, and a decrease of 5.56 % was observed in 2020 due to the COVID-19 lockdowns. Rising O 3 pollution reduced national level wheat, rice and maize yields by 14.51 % ± 0.43 %, 11.10 % ± 0.6 %, and 3.99 % ± 0.11 %, respectively. A Business-As-Usual projection suggested that the relative yield loss (RYL) would potentially reach 8 %–18 % at the national scale by 2050 if no emission control is implemented. COVID-19 lockdowns in 2020 led to significantly reduced RYL for maize (0.52 %) and rice (2.17 %) but not for wheat (0.11 %), with the largest reduction (1.88 %–9.4 %) in North China Plain, highlighting the potential benefits of emission control. Our findings provided robust evidence that rising O 3 pollution has significantly affected China's crop yields, production and economic losses, underscoring the urgent need to curb O 3 pollution to safeguard food security, particularly in densely populated and industrialized regions.
Approaches to the interagency coordination of R&D policy adopted by the governments of five West European countries and the United States are described and analyzed comparatively in terms of four variables: (1) pr...
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Approaches to the interagency coordination of R&D policy adopted by the governments of five West European countries and the United States are described and analyzed comparatively in terms of four variables: (1) procedures; (2) aims; (3) distribution and sources of influence among participating agencies; and (4) the frame of reference which orders governmental actions in R&D for coordination purposes. Differences stem from general features of policy formation within each system and changes over time in the conception and goals of “science policy”. The inherent ambiguities of the coordination concept and the difficulties in defining the “perfectly coordinated” system are the primary obstacles in evaluating coordination formats both within and across
A substantial literature on risk perception demonstrates the limits of human rationality, especially in the face of catastrophic risks. Human judgment, it seems, is flawed by the tendency to overestimate the magnitude...
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The room-temperature tetragonal-to-cubic transformation in BaTiO3 powders with decreasing particle size has been carefully studied, using materials prepared mainly by hydrothermal methods. Hydrothermal BaTiO3 powders ...
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The room-temperature tetragonal-to-cubic transformation in BaTiO3 powders with decreasing particle size has been carefully studied, using materials prepared mainly by hydrothermal methods. Hydrothermal BaTiO3 powders exhibited a more uniform particle size distribution than oxalate-route powders, with x-ray diffraction and electron microscopy indicating that powders less than or equal to 0.19 mu m in size were fully cubic while powders greater than or equal to 0.27 mu m were completely tetragonal (within a 5% detection limit for cubic material) at room temperature. The tetragonal-to-cubic transformation temperature was also found to lie int he range of 121 degrees +/- 3 degrees C for BaTiO3 powders with room-temperature (c/a) values > 1.008. No transformation could be detected using differential scanning calorimetry for BaTiO3 particles with a (c/a) < 1.008 at room temperature. BaTiO3 powder with a particle size just too small (0.19 mu m) to be tetragonal at room temperature remained cubic down to 80 K. Different models for the cubic-to-tetragonal room-temperature transformation are discussed. Hydroxyl ions do not appear to greatly affect the cubic-to-tetragonal transformation, which appears to be essentially dependent on particle size. It is concluded that a model based on surface free energy, as previously discussed for the monoclinic-to-tetragonal transformation at room temperature of fine ZrO2 particles, is consistent with the experimental data.
This paper shows how ethnographic research methods can be valuable tools for examining complex human/automation issues in commercial aviation. Ethnography is a participant/observer technique adapted from anthropology ...
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The introduction of genetically modified (GM) food crops has generated considerable debate over the role of public participation in science and technology decision-making. In 2002 and 2003 the newly established Office...
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