A new inventory of air pollutant emissions in Asia in the year 2006 is developed to support the Intercontinental Chemical Transport Experiment-Phase B (INTEX-B) funded by the National Aeronautics and ...Space Administration (NASA). Emissions are estimated for all major anthropogenic sources, excluding biomass burning. We estimate total Asian anthropogenic emissions in the year 2006 as follows: 47.1 Tg SO2, 36.7 Tg NOx, 298.2 Tg CO, 54.6 Tg NMVOC, 29.2 Tg PM10, 22.2 Tg PM2.5, 2.97 Tg BC, and 6.57 Tg OC. We emphasize emissions from China because they dominate the Asia pollutant outflow to the Pacific and the increase of emissions from China since 2000 is of great concern. We have implemented a series of improved methodologies to gain a better understanding of emissions from China, including a detailed technology-based approach, a dynamic methodology representing rapid technology renewal, critical examination of energy statistics, and a new scheme of NMVOC speciation for model-ready emissions. We estimate China's anthropogenic emissions in the year 2006 to be as follows: 31.0 Tg SO2, 20.8 Tg NOx, 166.9 Tg CO, 23.2 Tg NMVOC, 18.2 Tg PM10, 13.3 Tg PM2.5, 1.8 Tg BC, and 3.2 Tg OC. We have also estimated 2001 emissions for China using the same methodology and found that all species show an increasing trend during 2001–2006: 36% increase for SO2, 55% for NOx, 18% for CO, 29% for VOC, 13% for PM10, and 14% for PM2.5, BC, and OC. Emissions are gridded at a resolution of 30 min×30 min and can be accessed at our web site (http://mic.greenresource.cn/intex-b2006).
We present one case study of magnetic islands and energetic electrons in the reconnection diffusion region observed by the Cluster spacecraft. The cores of the islands are characterized by strong ...core magnetic fields and density depletion. Intense currents, with the dominant component parallel to the ambient magnetic field, are detected inside the magnetic islands. A thin current sheet is observed in the close vicinity of one magnetic island. Energetic electron fluxes increase at the location of the thin current sheet, and further increase inside the magnetic island, with the highest fluxes located at the core region of the island. We suggest that these energetic electrons are firstly accelerated in the thin current sheet, and then trapped and further accelerated in the magnetic island by betatron and Fermi acceleration.
Key Points
Strong core fields, density depletion, intense currents inside magnetic islands
Energetic electron increase in the thin current sheet, and magnetic island
Energetic electrons are first accelerated in thin current sheet, then in island
This study is the first evaluation of dynamical downscaling using the Weather Research and Forecasting (WRF) Model on a 4 km × 4 km high resolution scale in the eastern US driven by the new Community ...Earth System Model version 1.0 (CESM v1.0). First we examined the global and regional climate model results, and corrected an inconsistency in skin temperature during the downscaling process by modifying the land/sea mask. In comparison with observations, WRF shows statistically significant improvement over CESM in reproducing extreme weather events, with improvement for heat wave frequency estimation as high as 98%. The fossil fuel intensive scenario Representative Concentration Pathway (RCP) 8.5 was used to study a possible future mid-century climate extreme in 2057-9. Both the heat waves and the extreme precipitation in 2057-9 are more severe than the present climate in the Eastern US. The Northeastern US shows large increases in both heat wave intensity (3.05 °C higher) and annual extreme precipitation (107.3 mm more per year).
We present the first comprehensive observations of turbulence properties within high speed reconnection jet in the plasma sheet with moderate guide field. The power spectral density index is about ...−1.73 in the inertial range, and follows the value of −2.86 in the ion dissipation range. The turbulence is strongly anisotropic in the wave‐vector space with the major power having its wave‐vector highly oblique to the ambient magnetic field, suggesting that the turbulence is quasi‐2D. The measured “dispersion relations” obtained using the k‐filtering technique are compared with theory and are found to be consistent with the Alfvén‐Whistler mode. In addition, both Probability Distribution Functions and flatness results show that the turbulence in the reconnection jet is intermittent (multifractal) at scales less than the proton gyroradius/inertial lengths. The estimated electric field provided by anomalous resistivity caused by turbulence is about 3 mV/m, which is close to the typical reconnection electric field in the magnetotail.
Key Points
The turbulence is strongly anisotropic, and intermittent
The measured dispersion relations are consistent with the Alfven‐Whistler mode
The electric field caused by turbulence is close to typical reconnection field
The Atmosphere Radiation Measurements Program's Ancillary Facility (AAF/SMART‐COMMIT) was deployed to Zhangye (39.082°N, 100.276°E), which is located in a semidesert area of northwest China, during ...the period of late April to mid June in 2008. We selected 11 cases to retrieve dust aerosol optical depth (AOD), Angstrom exponent, size distribution, single‐scattering albedo (SSA) and asymmetry parameter (ASY) from multifilter rotating shadowband radiometer (MFRSR) measurements. These cases are dominated by large particles with Angstrom exponent values ranging from 0.34 to 0.93. The values of AOD at 0.67 μm range from 0.07 to 0.25. The mean SSA value increases with wavelength from 0.76 ± 0.02 at 0.415 μm to 0.86 ± 0.01 at 0.870 μm, while the mean ASY value decreases from 0.74 ± 0.04 to 0.70 ± 0.02. Before estimating dust aerosol direct radiative forcing, a radiative closure experiment was performed to verify that the retrieved aerosol optical properties and other input parameters to the radiative transfer model appropriately represent atmospheric conditions. The daytime‐averaged differences between model simulations and ground observations are −8.5, −2.9, and −2.1 W m−2 for the total, diffuse, and direct normal fluxes, respectively. The mean difference in the instantaneous reflected solar fluxes at the top of atmosphere (TOA) between the model and CERES observations is 8.0 W m−2. The solar aerosol direct radiative forcing (ARF), averaged over a 24 h period, at the surface is −22.4 ± 8.9 W m−2, while the TOA ARF is small and has an average value of only 0.52 ± 1.69 W m−2. The daily averaged surface aerosol radiative forcing efficiency at 0.5 μm is −95.1 ± 10.3 W m−2τ−1. Our results illustrate that the primary role of dust aerosol is to alter the distribution of solar radiation within the climate system rather than to reflect solar energy to space. We assess the satellite aerosol optical depth products from Mutiangle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) observations by comparing them with our ground‐based retrievals. Reasonable agreements with the ground‐based observations are found for the MISR product and MODIS Deep Blue product.
Mutation of highly conserved residues in transcription factors may affect protein-protein or protein-DNA interactions, leading to gene network dysregulation and human disease. Human mutations in ...GATA4, a cardiogenic transcription factor, cause cardiac septal defects and cardiomyopathy. Here, iPS-derived cardiomyocytes from subjects with a heterozygous GATA4-G296S missense mutation showed impaired contractility, calcium handling, and metabolic activity. In human cardiomyocytes, GATA4 broadly co-occupied cardiac enhancers with TBX5, another transcription factor that causes septal defects when mutated. The GATA4-G296S mutation disrupted TBX5 recruitment, particularly to cardiac super-enhancers, concomitant with dysregulation of genes related to the phenotypic abnormalities, including cardiac septation. Conversely, the GATA4-G296S mutation led to failure of GATA4 and TBX5-mediated repression at non-cardiac genes and enhanced open chromatin states at endothelial/endocardial promoters. These results reveal how disease-causing missense mutations can disrupt transcriptional cooperativity, leading to aberrant chromatin states and cellular dysfunction, including those related to morphogenetic defects.
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•Systems-level approach reveals GATA4 roles in human cardiac development and function•Heterozygous GATA4 missense mutation impairs cardiac gene program•GATA4 G296S mutation disrupts TBX5 genome occupancy at cardiac super-enhancers•PI3K signaling is a key “hub” in the GATA4 gene regulatory network
A human missense mutation that causes congenital heart defects disrupts the cooperation between transcription factors at cardiac super-enhancers and gives rise to aberrant gene expression.
Novel polymer grafted metal-organic framework (MOF) nanoparticles were synthesized. The formed core/shell nanoparticles exhibit outstanding water dispersity and pH sensitivity, and show their ...catalytic effect for the reduction reaction of 4-nitrophenol (NP) to 4-aminophenol (AP) when loaded with Pd(0) catalyst.
Flow regimes are believed to be of major evolutionary significance in fish. The flow regimes inhabited by cyprinids vary extensively from still flow regimes to riptide flow regimes. To test (i) ...whether flow‐driven swimming performance and relevant morphological differentiation are present among fish species and (ii) whether evolutionary shifts between high‐flow and low‐flow habitats in cyprinids are associated with evolutionary trade‐offs in locomotor performance, we obtained data on both steady and unsteady swimming performance and external body shape for 19 species of cyprinids that typically occur in different flow regimes (still, intermediate and riptide). We also measured the routine energy expenditure (RMR) and maximum metabolic rate (MMR) and calculated the optimal swimming speed. Our results showed that fish species from riptide groups tend to have a higher critical swimming speed (Ucrit), maximum linear velocity (Vmax) and fineness ratio (FR) than fish from the other two groups. However, there was no correlation between the reconstructed changes in the steady and unsteady swimming performance of the 19 species. According to the phylogenetically independent contrast (PIC) method, the Ucrit was actively correlated with the MMR. These results indicated that selection will favour both higher steady and unsteady swimming performance and a more streamlined body shape in environments with high water velocities. The results suggested that steady swimming performance was more sensitive to the flow regime and that for this reason, changes in body shape resulted more from selective pressure on steady swimming performance than on unsteady swimming performance. No evolutionary trade‐off was observed between steady and unsteady swimming performance, although Ucrit and MMR were found to have coevolved. However, a further analysis within each typically occurring habitat group suggested that the trade‐off that may exist between steady and unsteady swimming performance may be concealed by the effect of habitat.
A high O3 episode was detected in urban Shanghai, a typical city in the Yangtze River Delta (YRD) region in August 2010. The CMAQ integrated process rate method is applied to account for the ...contribution of different atmospheric processes during the high pollution episode. The analysis shows that the maximum concentration of ozone occurs due to transport phenomena, including vertical diffusion and horizontal advective transport. Gas-phase chemistry producing O3 mainly occurs at the height of 300–1500 m, causing a strong vertical O3 transport from upper levels to the surface layer. The gas-phase chemistry is an important sink for O3 in the surface layer, coupled with dry deposition. Cloud processes may contribute slightly to the increase of O3 due to convective clouds or to the decrease of O3 due to scavenging. The horizontal diffusion and heterogeneous chemistry contributions are negligible during the whole episode. Modeling results show that the O3 pollution characteristics among the different cities in the YRD region have both similarities and differences. During the buildup period, the O3 starts to appear in the city regions of the YRD and is then transported to the surrounding areas under the prevailing wind conditions. The O3 production from photochemical reaction in Shanghai and the surrounding area is most significant, due to the high emission intensity in the large city; this ozone is then transported out to sea by the westerly wind flow, and later diffuses to rural areas like Chongming island, Wuxi and even to Nanjing. The O3 concentrations start to decrease in the cities after sunset, due to titration of the NO emissions, but ozone can still be transported and maintain a significant concentration in rural areas and even regions outside the YRD region, where the NO emissions are very small.
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