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Takashi Nakamura, Hitomi Tanimoto, Masayuki Okamoto, Mitsuaki Takeuchi, Yoshiharu Tsubamoto, Hitoshi Noda Biological Research Group Drug Discovery Laboratories, Sanwa Kagaku Kenkyusho, Mie, JapanCorrespondence: Takashi NakamuraSanwa Kagaku Kenkyusho, Biological Research Group Drug Discovery Laboratories, 363 Shiosaki, Hokusei-Cho, Inabe-City, Mie, 511-0406, JapanTel +81-594-72-6221Fax +81-594-72-0071Email ta_nakamura@mb4.skk-net.comIntroduction: Glucose-dependent insulinotropic polypeptide (GIP) plays a crucial role in the regulation of lipid metabolism via lipoprotein lipase (LPL). GIP receptor antagonist, SKL-14959, suppressed the weight gain in the diet-induced obesity model. However, the mechanism is not unclear. Therefore, we aimed to give insight into the reason.Methods: Mice were divided into three groups of the low-fat diet, high-fat diets mixture with or without SKL-14959 for 151 days, and were monitored body weight and food consumption through the test. Oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were also performed. After that, blood, liver, muscle and adipose tissue were collected. Blood samples were measured glycosylated hemoglobin A1c (HbA1c), glucose, insulin, GIP level and plasma LPL activity. Triacylglycerol (TG) contents of liver and muscles were also measured. Moreover, a simple correlation analysis was performed.Results: SKL-14959 suppressed the body weight gain, decreased body mass index (BMI), HbA1c, and fasting glucose level, and trended to decline adipose tissues weight and TG contents compared with the vehicle, and inhibited plasma LPL activity. OGTT and ITT in the SKL-14959 group were not significantly changed relative to the vehicle. Additionally, upon treatment with SKL-14959 treatment, weight gain had weak correlation with lipase activity. Furthermore, lipase activity was associated with the fat mass and not white but red muscle TG contents and liver TG contents were not associated with lipase activity but HbA1c.In Conclusion: SKL-14959 might direct lipids metabolism to catabolism by inhibition of plasma LPL activity, resulting in the suppression of weight gain on diets-induced obesity mice.Keywords: GIP, GIP receptor antagonist, anti-obesity, lipase activity, lipid metabolism

The computational balance between the model grid resolution and the complexity of the data assimilation technique is essential for accurate aerosol forecasting and obtaining aerosol reanalysis data sets. This study aimed to develop a high‐resolution aerosol assimilation system. A 2‐dimensional variational method (2DVar) was implemented in a non‐hydrostatic icosahedral atmospheric model (NICAM). This new model (NICAM/2DVar), with a global grid size of 56 km, assimilated the observed aerosol optical depth (AOD) that is estimated by combining multiple products of geostationary and polar‐orbital satellites. The model results were evaluated against ground‐based AOD observations on a global scale. They exhibited higher correlations, lower uncertainties, and lower biases than those obtained without the 2DVar. The model also reproduced the observed surface aerosols (PM2.5) mass concentrations, especially in Kyushu, Japan. This occurred because the satellite‐estimated AODs over ocean close to air pollution sources were obtained for many occasions. The correlation coefficient values against the PM2.5 observations increased from 0.44 to 0.65 compared to the results without the 2DVar. The impact of the 2DVar on the forecast results was investigated, and the forecast values for 2–3 days were improved. Because satellite‐retrieved AODs are often lacking over land owing to retrieval difficulties, the use of ground‐based AODs in assimilations is essential for precise processing the of aerosol reanalysis data sets. The computational cost with the use of the 2DVar was only 0.6% more than that without its use. Thus, aerosol assimilation using the NICAM/2DVar can be realistically extended to finer grid sizes. Plain Language Summary: High‐resolution models and data assimilation techniques should be used to obtain more accurate aerosol distributions. We combined a high‐resolution model and an assimilation method at a low computational cost. We also integrated multiple aerosol satellite products. The new procedure successfully reproduced the aerosol observations. The results were significantly better when observations for multiple grids and times were available. Surface measurements on land, for which satellites often lack aerosol signals, are helpful. Key Points: Combined geostationary and polar orbital satellite aerosol products were assimilatedThe aerosol assimilation results improved with increasing spatiotemporal coverage of the observationsEven though the column‐integrated aerosol optical depth was assimilated, surface aerosol (PM2.5) concentration improved [ABSTRACT FROM AUTHOR]

Measurements of the major reactive nitrogen species (NOy)i (NOx, peroxyacyl nitrates, HNO3, and particulate nitrate (NO3-), total reactive nitrogen (NOy), volatile organic compounds, OH and HO2, and organic aerosol were made near the urban center of Tokyo in different seasons of 2003-2004 to study the processes involving oxidized forms of reactive nitrogen and O3. Generally, NOx constituted the dominant fraction of NOy throughout the seasons. The NOx/NOy and HNO3/NOy ratios were lowest and highest, respectively, in summer, owing to the seasonally high OH concentration. The fraction of NOy that remained in the atmosphere after emission (RNOy) decreased with the decrease in the NOx/NOy ratio in summer and fall. It is likely that the median seasonal-diurnal variations Of Ox = O3 + NO2 were controlled by those of the background O3 levels, photochemical O3 formation, and vertical transport. Ox showed large increases during midday under stagnant conditions in mid-August 2004. Their in situ production rates calculated by a box model were too slow to explain the observed increases. The high Ox was likely due to the accumulation of Ox from previous days in the upper part of the boundary layer (BL) followed by transport down to near the surface by mixing after sunrise. Considering the tight correlation between Ox and secondary organic aerosol (SOA), it is likely that SOA also accumulated during the course of sea-land breeze circulation in the BL. Copyright 2008 by the American Geophysical Union.

[ 1] Tropospheric carbon monoxide ( CO) was measured throughout 2001 using groundbased Fourier transform IR ( FTIR) spectrometers at Moshiri (44.4 degrees N) and Rikubetsu (43.5 degrees N) observatories in northern Japan, which are separated by 150 km. Seasonal and day-to-day variations of CO are studied using these data, and contributions from various CO sources are evaluated using three-dimensional global chemistry transport model (GEOS-CHEM) calculations. Seasonal maximum and minimum FTIR-derived tropospheric CO amounts occurred in April and September, respectively. The ratio of partial column amounts between the 0 - 4 and 0 - 12 km altitude ranges is found to be slightly greater in early spring. The GEOS-CHEM model calculations generally reproduce these observed features. Source-labeled CO model calculations suggest that the observed seasonal variation is caused by seasonal contributions from various sources, in addition to a seasonal change in chemical CO loss by OH. Changes in meteorological fields largely control the relative importance of various source contributions. The contributions from fossil fuel (FF) combustion in Asia and photochemical CO production have the greatest yearly averaged contribution at 1 km among the CO sources (31% each). The Asian FF contribution increases from winter to summer, because weak southwesterly wind in summer brings more Asian pollutants to the observation sites. The seasonal variation from photochemical CO production is small ( +/- 17% at 1 km), likely because of concurrent increases ( decreases) of photochemical production and loss rates in summer ( winter), with the largest contribution between August and December. The contribution from intercontinental transport of European FF combustion CO is found to be comparable to that of Asian FF sources in winter. Northwesterly wind around the Siberian high in this season brings pollutants from Europe directly to Japan, in addition to southward transport of accumulated pollution from higher latitudes. The influences are generally greater at lower altitudes, resulting in a vertical gradient in the CO profile during winter. The model underestimates total CO by 12 - 14% between March and June. Satellite-derived fire-count data and the relationship between FTIR-derived HCN and CO amounts are generally consistent with biomass burning influences, which could have been underestimated by the model calculations.

The magnetic properties and structures of Ni and NiFe nanocrystalline films prepared with the gas-deposition method (GDM) are investigated. From the results of STM and SEM, fine particles, approximately 10 nm in diameter, were seen in the films. Furthermore, aggregates several tens of nm in diameter, composed of the small particles, are also observed. The magnetization of the Ni nanocrystalline films is about 50 emu/g, or 90% of that of bulk Ni. Coercivity of the Ni nanocrystals ranged from 4 to 20 Oe. In the case of NiFe, the concentration of Fe is slightly increased as the evaporation temperature is increased.