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Abstract. As a part of the CAREBeijing-2008 campaign, observations of O 3 , oxides of nitrogen (NO x and NO y ), CO, and hydrocarbons (NMHCs) were carried out at the air quality observatory of the Peking University in Beijing, China during August 2008, including the period of the 29th Summer Olympic Games. The measurements were compared with those of the CAREBeijing-2006 campaign to evaluate the effectiveness of the air pollution control measures, which were conducted for improving the air quality in Beijing during the Olympics. The results indicate that significant reduction in the emissions of primary air pollutants had been achieved; the monthly averaged mixing ratios of NO x , NO y , CO, and NMHCs decreased by 42.2, 56.5, 27.8, and 49.7 %, respectively. In contrast to the primary pollutants, the averaged mixing ratio of O 3 increased by 42.2 %. Nevertheless, it was revealed that the ambient levels of total oxidant (O x = O 3 +NO 2 +1.5NO z ) and NO z were reduced by 21.3 and 77.4 %, respectively. The contradictions between O 3 and O x were further examined in two case studies. Ozone production rates of 30-70 ppbv h −1 and OPEx of ∼8 mole mole −1 were observed on a clear-sky day in spite of the reduced levels of precursors. In that case, it was found that the mixing ratio of O 3 increased with the increasing NO 2 /NO ratio, whereas the NO z mixing ratio leveled off when NO 2 /NO>8. Consequently, the ratio of O 3 to NO z increased to above 10, indicating the shift from VOC-sensitive regime to NO x -sensitive regime. However, in the other case, it was found that the O 3 production was inhibited significantly due to substantial reduction in the NMHCs. According to the observations, it was suggested that the O 3 and/or O x production rates in BeijingCorrespondence to: C. C.-K. Chou (ckchou@rcec.sinica.edu.tw) should have been reduced as a result of the reduction in the emissions of precursors during the Olympic period. However, the nighttime O 3 levels increased due to a decline in the NO-O 3 titration, and the midday O 3 peak levels were elevated because of the shift in the photochemical regime and the inhibition of NO z formation.

SummaryA quantitative and non-occlusive deep vein thrombosis model was developed in rabbits. We used this model to test the antithrombotic activity of the prothrombinase complex inhibitors factor rXai and its chemical analog glutamyl-glycyl-arginyl chloromethyl ketone inactivated human factor Xa (EGR-Xai), along with the thrombin inhibitors D-phenylalanyl-prolyl-arginyl chloromethyl ketone (PPACK) and heparin. Dose dependent effects of the inhibitors during constant infusion were monitored. Measurements included thrombus weights, hemostatic parameters and both cuticle and ear bleeding times. In this model, factor rXai and EGR-Xai had comparable in-vivo efficacy, and showed 80%-93% inhibition at plasma levels of 6.5 nM (rXai) and 8 nM (EGR-Xai). Effects on ex-vivo clotting times varied among the inhibitors. At 80-100% thrombus inhibition, factor rXai and EGR-Xai had no statistically significant effect, while PPACK extended thrombin clotting time (TCT) times 2.3-fold, and heparin prolonged both activated partial thromboplastin time (APTT), prothrombin time (PT) and TCT ex-vivo clotting times 6.9-, 1.2-, and 7-fold respectively. At these dosages, cuticle and ear bleeding times were prolonged for all inhibitors and showed increases of 177%-389% (cuticle) and 45%-129% (ear). Our results demonstrate that direct inhibition of prothrombinase complex assembly is effective in arresting venous thrombosis.

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Two contrasting localized heavy rainfall events during Taiwan's early summer rainy season with the daily rainfall maximum along the windward mountain range and coast were studied and compared using a combination of observations and numerical simulations. Both events occurred under favorable large-scale settings including the existence of a moisture tongue from the tropics. For the 31 May case, heavy rainfall occurred in the afternoon hours over the southwestern windward slopes after a shallow surface front passed central Taiwan. The orographic lifting of the prevailing warm, moist, west-southwesterly flow aloft, combined with a sea breeze-upslope flow at the surface provided the localized lifting needed for the development of heavy precipitation. On 16 June before sunrise, pronounced orographic blocking of the warm, moist, south-southwesterly flow occurred because of the presence of relatively cold air at low levels as a result of nocturnal and rain evaporative cooling. As a result, convective systems intensified as they moved toward the southwestern coast. During the daytime, the cold pool remained over southwestern Taiwan without the development of onshore/upslope flow. Furthermore, with a south-southwesterly flow aloft parallel to terrain contours, orographic lifting aloft was absent and preexisting rain cells offshore diminished after they moved inland. Over northern Taiwan on the lee side, a sea breeze/onshore flow developed in the afternoon hours, resulting in heavy thundershowers. These results demonstrate the importance of diurnal and local effects on determining the location and timing of the occurrences of localized heavy precipitation during the early summer rainy season over Taiwan.

This study characterizes and compares the chemical composition of fog water at four sites in Taiwan. Fog was sampled with identical active fog collectors (modified Caltech design) using identical sampling strategies at all four sites. While the sites varied largely in terms of altitude above mean sea level (asl), type of fog, and the potential sources of constituents in fog water, the chemical composition of fog water was in all cases clearly dominated by H + , NH 4 + , NO 3 -and SO 4 2-, making up more than 85% of the total ion concentrations. The pH ranged from 2.27 to 5.95.Sulfur dioxide emissions from coal combustion in Mainland China and Taiwan as well as nitrogen oxide emissions from urbanized central-west Taiwan and the greater Taipei region were the main precursors of fog acidity. Ammonia, originating from agriculture emissions, was the main neutralizer. The Kinmen site (48 m asl), situated on an island close to Mainland China, exhibited the lowest pH and the highest sulfate concentrations. At the Xitou site on the western slopes of the Taiwan Central Mountain Range (1150 m asl), ammonium from agriculture dominated and lead to relatively high pH. At the same time, the nitrate/sulfate ratio was highest at this site (> 1 in equivalent units), resulting from relatively large contributions from street traffic. The ion concentrations at the Chilan site (1650 m asl) and the Lulin high mountain site (2862 m asl) were much lower than those at Xitou and Kinmen. While the ion concentrations at Chilan were considerably lower than at Lulin, the ion loadings, which is the amount of dissolved ions per volume of air, were similar at Chilan and Lulin.