Assessment of air quality benefits from national air pollution control policies in China. Part II: Evaluation of air quality predictions and air quality benefits assessment

Following the meteorological evaluation in Part I, this Part II paper presents the statistical evaluation of air quality predictions by the U.S. Environmental Protection Agency (U.S. EPA)’s Community Multi-Scale Air Quality (Models-3/CMAQ) model for the four simulated months in the base year 2005. The surface predictions were evaluated using the Air Pollution Index (API) data published by the China Ministry of Environmental Protection (MEP) for 31 capital cities and daily fine particulate matter (PM_2.5, particles with aerodiameter less than or equal to 2.5 μm) observations of an individual site in Tsinghua University (THU). To overcome the shortage in surface observations, satellite data are used to assess the column predictions including tropospheric nitrogen dioxide (NO₂) column abundance and aerosol optical depth (AOD). The result shows that CMAQ gives reasonably good predictions for the air quality.The air quality improvement that would result from the targeted sulfur dioxide (SO₂) and nitrogen oxides (NO_x) emission controls in China were assessed for the objective year 2010. The results show that the emission controls can lead to significant air quality benefits. SO₂ concentrations in highly polluted areas of East China in 2010 are estimated to be decreased by 30–60% compared to the levels in the 2010 Business-As-Usual (BAU) case. The annual PM_2.5 can also decline by 3–15 μg m^?3 (4–25%) due to the lower SO₂ and sulfate concentrations. If similar controls are implemented for NO_x emissions, NO_x concentrations are estimated to decrease by 30–60% as compared with the 2010 BAU scenario. The annual mean PM_2.5 concentrations will also decline by 2–14 μg m^?3 (3–12%). In addition, the number of ozone (O₃) non-attainment areas in the northern China is projected to be much lower, with the maximum 1-h average O₃ concentrations in the summer reduced by 8–30 ppb.     

Reproductive toxicity of metals in calanoid copepods

This study investigated the effect of exposure route on metal accumulation, tissue distribution, and toxicity in the marine copepods Acartia hudsonica and A. tonsa. Sublethal toxicity was measured as decreases in egg production, hatching rate, ovarian development and protein (yolk) content of the egg. When algal food, exposed to Hg at 1 nM or Cd at 5 nM resulting in cells containing 34 and 64 nmol metal g^-1 dry weight, respectively, was ingested over a 4-h period by copepods, the total copepod body burden increased nine-fold for Hg and two-fold for Cd over background concentrations, and egg production decreased by 50%. Sublethal concentrations of metals were >2 orders of magnitude lower than LC₅₀ concentrations. Hatching rate, ovarian development and egg protein content all decreased following trophic exposure to metals, implying that the process of yolk accumulation (vitellogenesis) was affected. Exposure to dissolved Cd had no effect, but dissolved Hg at concentrations as low as 0.25 nM did affect egg production. Different toxic effects following different exposure routes were related to different metal distributions in the copepods: exposure to dissolved metal resulted in metal deposition in the exoskeleton, whereas exposure to dietary metal resulted in metal deposition in internal tissues. These findings indicate that enrichment of metal concentrations in internal tissues, which occurs primarily after exposure to dietary metal, affects vitellogenesis. The reproduction rate decreases by about 75% at metal concentrations only moderately higher than levels in coastal waters. Toxicity tests involving aquatic animals need to consider effects following uptake by different pathways, including the trophic transfer of metals.     

Differences in volatile methyl siloxane (VMS) profiles in biogas from landfills and anaerobic digesters and energetics of VMS transformations

The objectives of this study were to compare the types and levels of volatile methyl siloxanes (VMS) present in biogas generated in the anaerobic digesters and landfills, evaluate the energetics of siloxane transformations under anaerobic conditions, compare the conditions in anaerobic digesters and municipal solid waste (MSW) landfills which result in differences in siloxane compositions. Biogas samples were collected at the South District Wastewater Treatment Plant and South Dade Landfill in Miami, Florida. In the digester gas, D4 and D5 comprised the bulk of total siloxanes (62% and 27%, respectively) whereas in the landfill gas, the bulk of siloxanes were trimethylsilanol (TMSOH) (58%) followed by D4 (17%). Presence of high levels of TMSOH in the landfill gas indicates that methane utilization may be a possible reaction mechanism for TMSOH formation. The free energy change for transformation of D5 and D4 to TMSOH either by hydrogen or methane utilization are thermodynamically favorable. Either hydrogen or methane should be present at relatively high concentrations for TMSOH formation which explains the high levels present in the landfill gas. The high bond energy and bond distance of the Si–O bond, in view of the atomic sizes of Si and O atoms, indicate that Si atoms can provide a barrier, making it difficult to break the Si–O bonds especially for molecules with specific geometric configurations such as D4 and D5 where oxygen atoms are positioned inside the frame formed by the large Si atoms which are surrounded by the methyl groups.     

Disappearance and dispersal of Spermophilus elegans juveniles in relation to behavior

Summary Patterns of disappearance and dispersal of Spermophilus elegans juveniles during the first 6-weeks postemergence were compared for 1977 and 1978 and related to quantitative and qualitative changes in social interaction involving juveniles.Juvenile disappearance (emigration or mortality) and dispersal within the study site varied between the sexes within and between years. Female disappearance and dispersal were significantly greater in 1977, and male losses in 1978 significantly exceeded male losses in 1977. Greater female loss in 1977 resulted in total male — female losses being equivalent, whereas in 1978 juvenile loss was strongly biased toward males by the end of the 6-week period.Greater female loss in 1977 was attributed primarily to increased aggression between female juveniles in that year because of larger average litter size with more females per litter. Increased disappearance of males in 1978 showed no correlation with litter size or relative increase in number of males per litter. Male young interacted with individuals of several age/sex classes, and a possible behavioral influence on male disappearance was increased aggressiveness by yearling males toward juvenile males in 1978.Behavior appeared to act as a proximate factor in juvenile disappearance and dispersal, and the observed differences between how male and female juveniles interacted in 1977 and 1978 were hypothesized to reflect the operation of different selective pressures to increase individual male or female fitness.     

绿色团队

当主流商学院开始将更多的企业社会责任（CSR）话题带入教室时，一些教育家仍认为这些机构的努力不够。他们相信，现在所需要的，是围绕可持续发展概念来确定MBA教学大纲，大纲仍然讲授基础科目，但要染上绿色。     

Functional reference in an alarm signal given during nest defence: seet calls of yellow warblers denote brood-parasitic brown-headed cowbirds

Field observations and model-presentation experiments have shown that yellow warblers (Dendroica petechia) produce seet calls preferentially in response to brood-parasitic brown-headed cowbirds (Molothrus ater). In this study, we investigated whether seet calls are functionally referential alarm calls denoting cowbirds by determining whether female warblers responded appropriately to seet calls in the absence of a cowbird, whether alarm calling by warblers varied with response urgency, and how warblers in a population allopatric with cowbirds responded to cowbird and avian predator models and seet playbacks. As a control, we presented chip calls, which are elicited by nest predators as well as by non-threatening intruders, but are not strongly associated with cowbirds. Yellow warblers responded differently to playbacks of seet than chip calls. To seet playbacks, almost 60% of females gave seet calls and rushed to sit in their nests, responses typically elicited by cowbirds, whereas these responses were given infrequently in response to chip calls. Yellow warblers seet called equally in situations that simulated low, medium and high risk of parasitism, which suggests that these calls did not vary with response urgency. In a population allopatric with cowbirds, seet calls were rarely produced in response to cowbird or avian nest predator models and never to seet playbacks. These results suggest that seet calls are functionally referential signals denoting cowbirds and that cowbird parasitism was a strong selective pressure in the evolution of functional referentiality in the seet call of yellow warblers.Communicated by W.A. Searcy     

Testis size variation in frogs: testing the alternatives

While sperm competition may be a major factor affecting relative testis size in vertebrates as a whole, additional hypotheses have not been given much attention in frogs. This is important because sperm competition is relatively uncommon in frogs and relative testis size varies in frogs that do not have multiple-male breeding systems. This paper tests two additional hypotheses for differences in relative testis size among frogs: relative clutch size (number of eggs/snout vent length) and androgen level. Testis size was measured in 90 species of frogs belonging to five families. Relative testis size was found to be positively correlated with relative clutch size in species that lack sperm competition. Mean androgen levels of species also positively covaried with relative testis size. However, there was no correlation between relative testis size and level of male agonistic behavior among species, despite other work indicating that testosterone levels are positively correlated with agonistic behavior in at least some species. These findings suggest that a number of factors in addition to sperm competition are important in the evolution of testis size in male frogs. Received: 17 January 1997 / Accepted after revision: 23 June 1997     

Structure and freedom in creativity: The interplay between externally imposed structure and personal cognitive style

This research investigates how creativity is influenced by externally imposed structure (how structured the task is), internal, cognitively produced, structure (how structured the individuals' cognitive style is), and the interaction between these two factors. Reviewing past literature, we find a contradiction. Studies that focused on the situational perspective found that externally imposed structure increases creativity. In contrast, studies that focused on the individual found that systematic (structured) cognitive style decreases creativity. In two empirical studies we investigated this seeming contradiction. We focused on two aspects of externally imposed structure: The construction of the task (Study 1) and the instructions provided (Study 2). The findings of both studies revealed that creativity was higher under structured conditions. We also show that intuitive individuals are more creative than systematic individuals, but mainly under free conditions, where structure is not externally imposed. Copyright © 2009 John Wiley & Sons, Ltd.