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[1] A three-dimensional regional chemical transport model, STEM 2K1, coupled with a detailed radiation model is used to study the influences of aerosols and clouds on photolysis rates and photochemical processes over East Asia-Western Pacific during the TRACE-P period. Measured J-values are compared with those calculated using three-dimensional modeled fields of clouds and aerosols. The model is shown to accurately represent observed J-values over a broad range of conditions. Model studies with and without aerosols and clouds are performed and compared with clear-sky conditions to isolate the various influences. Clouds are shown to have a large impact on photolysis rates during the observation periods of TRACE-P, with J[NO2] decreased by 20% below clouds and enhanced by ∼30% from 1 km to 8 km. Clouds also exert a dominant influence on short-lived radicals, like OH and HO2. For March, clouds reduce OH by 23% at altitudes below 1 km and increase OH by ∼25% above 1 km. Asian aerosols contain large amounts of carbonaceous material, inorganic components such as sulfates, and mineral oxides. These aerosols significantly influence J-values and photochemical processes. When averaged over all TRACE-P DC-8 and P-3 flights, the aerosol influence via affecting J-values reduces OH by ∼40% below 1 km, and by ∼24% above 1 km. Aerosols have a stronger impact on longer-lived chemical species than clouds do because aerosols tend to be coemitted with precursors and have a longer contact time with the polluted air masses. The accumulated aerosol impact generally is to reduce O3 concentrations by about 6 ppbv in the biomass burning plumes emitted from Southeast Asia. In megacity plumes, aerosols can increase NOx concentration by 40% via reducing its photolytic loss and reduce NOz concentration by a similar amount. A detailed case study of the DC-8 and P-3 flights on 27 March is used to make comparisons for cloud and aerosol influences. During these flights, the cloud impact on J-values is stronger than the aerosol impact, but aerosols are shown to exert a much stronger accumulated influence on O3 production.

[1] An inventory of air pollutant emissions in Asia in the year 2000 is developed to support atmospheric modeling and analysis of observations taken during the TRACE-P experiment funded by the National Aeronautics and Space Administration (NASA) and the ACE-Asia experiment funded by the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA). Emissions are estimated for all major anthropogenic sources, including biomass burning, in 64 regions of Asia. We estimate total Asian emissions as follows: 34.3 Tg SO2, 26.8 Tg NOx, 9870 Tg CO2, 279 Tg CO, 107 Tg CH4, 52.2 Tg NMVOC, 2.54 Tg black carbon (BC), 10.4 Tg organic carbon (OC), and 27.5 Tg NH3. In addition, NMVOC are speciated into 19 subcategories according to functional groups and reactivity. Thus we are able to identify the major source regions and types for many of the significant gaseous and particle emissions that influence pollutant concentrations in the vicinity of the TRACE-P and ACE-Asia field measurements. Emissions in China dominate the signature of pollutant concentrations in this region, so special emphasis has been placed on the development of emission estimates for China. China's emissions are determined to be as follows: 20.4 Tg SO2, 11.4 Tg NOx, 3820 Tg CO2, 116 Tg CO, 38.4 Tg CH4, 17.4 Tg NMVOC, 1.05 Tg BC, 3.4 Tg OC, and 13.6 Tg NH3. Emissions are gridded at a variety of spatial resolutions from 1° × 1° to 30 s × 30 s, using the exact locations of large point sources and surrogate GIS distributions of urban and rural population, road networks, landcover, ship lanes, etc. The gridded emission estimates have been used as inputs to atmospheric simulation models and have proven to be generally robust in comparison with field observations, though there is reason to think that emissions of CO and possibly BC may be underestimated. Monthly emission estimates for China are developed for each species to aid TRACE-P and ACE-Asia data interpretation. During the observation period of March/April, emissions are roughly at their average values (one twelfth of annual). Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of ±16% for SO2 to a high of ±450% for OC.

(� HCN/� CO � 0.0015) and potassium (� K + /� CO � 0.0038) but very low NOy (� NOy/ � CO � 0.005) mixingratios,whichmaybeassociated withthespecialburning condition in this region. The biomass burning air masses have high ozone production efficiency. The observedO3/� NOz values were � 17 in biomass events and 1.7 in other events. The BB influence on the trace gas distributions can be divided into two categories: the influence through direct reactions and the influence caused by BB aerosols changing J values. These two influences are discussed for the BB-affected TRACE-P flights and for east Asia. The BBinfluencesonchemicalspeciesarenotonlydeterminedbytheBBplumeintensitybutalso bytheambientenvironmentcausedbyotheremissions.InSoutheastAsia,wherethebiogenic emissions are very strong, the OH background concentration is low, and the BB gas-phase compounds mainly contribute to OH production. Arranged in the sensitivity to the J value change caused by BB aerosols, we have OH > HO2 > HCHO > O3 when evaluated on a regional average.AveragedoverMarch,thebiomassburningnetinfluenceisashighas50% forOH,40%forHO2,60%forHCHO,and10ppbvforO3forthelayersbelow1km. INDEX TERMS: 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0322 Atmospheric Composition and Structure: Constituent sources and sinks; 0345 Atmospheric Composition and Structure: Pollution—urbanandregional(0305);3337MeteorologyandAtmospheric Dynamics:Numericalmodelingand data assimilation; 3359 Meteorology and Atmospheric Dynamics: Radiative processes; KEYWORDS: biomass burning, chemical transport model, TRACE-P, photochemical process, aerosols, radiative influence Citation: Tang, Y., et al., Influences of biomass burning during the Transport and Chemical Evolution Over the Pacific (TRACE-P) experiment identified by the regional chemical transport model, J. Geophys. Res., 108(D21), 8824, doi:10.1029/2002JD003110, 2003.

We investigate the sources, prevalence, and fine-particle inorganic composition of biosmoke over the western Pacific Ocean between 24 February and 10 April 2001. The analysis is based on highly time-resolved airborne measurements of gaseous and fine- particle inorganic chemical composition made during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) experiment. At latitudes below approximately 25 deg. N, relatively pure biomass burning plumes of enhanced fine-particle potassium, nitrate, ammonium, light-absorbing aerosols, and CO concentrations were observed in plumes that back trajectories and satellite fire map data suggest originated from biomass burning in southeast Asia. Fine-particle water-soluble potassium (K+) is confirmed to be a unique biosmoke tracer, and its prevalence throughout the experiment indicates that approximately 20% of the TRACE-P Asian outflow plumes were influenced, to some extent, by biomass or biofuel burning emissions. At latitudes above 25 deg. N, highly mixed urban/industrial and biosmoke plumes, indicated by SO(sup 2, sub 4) and K+, were observed in 5 out of 53 plumes. Most plumes were found in the Yellow Sea and generally were associated with much higher fine-particle loadings than plumes lacking a biosmoke influence. The air mass back trajectories of these mixed plumes generally pass through the latitude range of between 34 deg. and 40 deg. N on the eastern China coast, a region that includes the large urban centers of Beijing and Tianjin. A lack of biomass burning emissions based on fire maps and high correlations between K+ and pollution tracers (e.g., S(sup 2, sub 4) suggest biofuel sources. Ratios of fine-particle potassium to sulfate are used to provide an estimate of relative contributions of biosmoke emissions to the mixed Asian plumes. The ratio is highly correlated with fine-particle volume (r(sup 2) = 0.85) and predicts that for the most polluted plume encounter in TRACE-P, approximately 60% of the plume is associated with biosmoke emissions. On average, biosmoke contributes approximately 35-40% to the measured fine inorganic aerosol mass in the mixed TRACE-P plumes intercepted north of 25% latitude.

[1] The Models-3 Community Multiscale Air Quality modeling system (CMAQ) coupled with the Regional Atmospheric Modeling System (RAMS) is used to analyze the Asian continental outflow of carbon monoxide (CO), ozone (O3), and aerosol sulfate (SO42−) to the western Pacific Ocean during the period 17–24 March 2001. In this time period eight airborne observations (DC-8 flights 11–14 and P-3B flights 13–16) of the NASA Transport and Chemical Evolution Over the Pacific (TRACE-P) mission were being conducted over a broad area covering Hong Kong, Okinawa, the East China Sea, and southern Japan. Comparison of model results with observations shows that the model reproduces the main observed features of CO, O3, and SO42−, including horizontal and vertical gradients, of the Asian pollution outflow over the western Pacific. Model results show that the fast boundary outflow from Asia to the western Pacific is largely restricted to the middle latitudes, and the maximum outflow fluxes are in the lower free atmosphere (3–6 km) north of 25°N. Simulations with and without biomass burning emissions are conducted to quantify the impacts of biomass burning on tropospheric concentrations of CO and O3. Biomass burning is found to contribute more than 50% of the CO concentrations and up to 40% of the O3 concentrations in the boundary layer over the major source regions. The largest percentage contributions to CO and O3 levels (up to 40% and 30%, respectively) over the western Pacific are in the lower free troposphere (2–6 km).

Estimates of biomass burning in Asia are developed to facilitate the modeling of Asian and global air quality. A survey of national, regional, and international publications on biomass burning is conducted to yield consensus estimates of 'typical' (i.e., non-year-specific) estimates of open burning (excluding biofuels). We conclude that 730 Tg of biomass are burned in a typical year from both anthropogenic and natural causes. Forest burning comprises 45% of the total, the burning of crop residues in the field comprises 34%, and 20% comes from the burning of grassland and savanna. China contributes 25% of the total, India 18%, Indonesia 13%, and Myanmar 8%. Regionally, forest burning in Southeast Asia dominates. National, annual totals are converted to daily and monthly estimates at 1{sup o} x 1{sup o} spatial resolution using distributions based on AVHRR fire counts for 1999--2000. Several adjustment schemes are applied to correct for the deficiencies of AVHRR data, including the use of moving averages, normalization, TOMS Aerosol Index, and masks for dust, clouds, landcover, and other fire sources. Good agreement between the national estimates of biomass burning and adjusted fire counts is obtained (R{sup 2} = 0.71--0.78). Biomass burning amounts are converted to atmospheric emissions, yielding themore » following estimates: 0.37 Tg of SO{sub 2}, 2.8 Tg of NO{sub x}, 1100 Tg of CO{sub 2}, 67 Tg of CO, 3.1 Tg of CH{sub 4}, 12 Tg of NMVOC, 0.45 Tg of BC, 3.3 Tg of OC, and 0.92 Tg of NH{sub 3}. Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of {+-}65% for CO{sub 2} emissions in Japan to a high of {+-}700% for BC emissions in India.« less

Texto completo: acesso restrito. p. 1293–1308 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-01-13T15:13:59Z No. of bitstreams: 1 Gregory R Carmichael.pdf: 1253796 bytes, checksum: 9345158c493a45da2a2756470c6418a1 (MD5) Made available in DSpace on 2014-01-13T15:13:59Z (GMT). No. of bitstreams: 1 Gregory R Carmichael.pdf: 1253796 bytes, checksum: 9345158c493a45da2a2756470c6418a1 (MD5) Previous issue date: 2003 Measurements of gaseous SO2, NH3, and O3 using IVL passive sampler technology were obtained during a pilot measurement program initiated as a key component of the newly established WMO/GAW Urban Research Meteorology and Environment (GURME) project. Monthly measurements were obtained at 50 stations in Asia, Africa, South America, and Europe. The median SO2 concentrations vary from a high of 13 ppb at Linan, China, to

Measurements of gaseous SO2, NH3, and O3 using IVL passive sampler technology were obtained during a pilot measurement program initiated as a key component of the newly established WMO/GAW Urban Research Meteorology and Environment (GURME) project. Monthly measurements were obtained at 50 stations in Asia, Africa, South America, and Europe. The median SO2 concentrations vary from a high of 13 ppb at Linan, China, to

[1] The regional-scale aerosol transport model (CFORS) is used in the analysis of black carbon (BC) observed at five remote Japanese islands during the ACE-Asia experiment. BC is modeled online in the regional-scale meteorological model, using emissions estimates for 2000. Two model experiments are conducted (1) a control run that includes all the BC emission, and (2) a sensitivity run without open biomass burning emissions to clarify the impact of biomass burning on the BC levels in the western Pacific. The regional aerosol model (CFORS) is shown to accurately reproduce many of the important features observed. Model analysis shows that the spatial and temporal distributions of black carbon between the northern sites (Rishiri and Sado; located in the Japan Sea) and the southern stations (Hachijo, Chichijima, and Amami-Oshima; in the western Pacific Ocean) are under different flow regimes. It is shown that the major synoptic features controlling BC levels are associated with outflow in the warm conveyor belt of traveling cold fronts and the subsequent postfrontal transport. At the northern stations (Rishiri and Sado), elevated BC concentrations are calculated to be mainly below the heights of 2000 m, and the biomass burning fraction is estimated to be below 20%. At the southern sites (e.g., Chichijima) the contribution due to biomass burning reaches 32% at the surface and 52% in the free atmosphere. CFORS results indicate that the major black carbon source and transport height are different between the northern and southern sites.

[1] We report here airborne measurements of atmospheric CO2 over the western North Pacific during the March–April 2001 Transport and Chemical Evolution over the Pacific (TRACE-P) mission. The CO2 spatial distributions were notably influenced by cyclogenesis-triggered transport of regionally polluted continental air masses. Examination of the CO2 to C2H2/CO ratio indicated rapid outflow of combustion-related emissions in the free troposphere below 8 km. Although the highest CO2 mixing ratios were measured within the Pacific Rim region, enhancements were also observed further east over the open ocean at locations far removed from surface sources. Near the Asian continent, discrete plumes encountered within the planetary boundary layer contained up to 393 ppmv of CO2. Coincident enhancements in the mixing ratios of C2Cl4, C2H2, and C2H4 measured concurrently revealed combustion and industrial sources. To elucidate the source distributions of CO2, an emissions database for Asia was examined in conjunction with the chemistry and 5-day backward trajectories that revealed the WNW/W sector of northeast Asia was a major contributor to these pollution events. Comparisons of NOAA/CMDL and JMA surface data with measurements obtained aloft showed a strong latitudinal gradient that peaked between 35° and 40°N. We estimated a net CO2 flux from the Asian continent of approximately 13.93 Tg C day−1 for late winter/early spring with the majority of the export (79%) occurring in the lower free troposphere (2–8 km). The apportionment of the flux between anthropogenic and biospheric sources was estimated at 6.37 Tg C day−1 and 7.56 Tg C day−1, respectively.

Background Polymylgia rheumatic (PMR) is an inflammatory rheumatic disease characterized by pain and stiffness in the shoulders, pelvic girdles and neck. PMR is generally associated with elevation of acute phase reactants such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Although PMR is often underestimated, it is common in the elderly from Western countries, and the prevalence was apparently different according to race until now. Standard therapy is oral steroids, but there is considerable heterogeneity in pateints’ clinical courses, steroid requirements for suppression of symptoms and the likelihood of relapses. An epidemiologic study of PMR in Korea is limited. Objectives This study aims to find the clinical characteristics and prognostics factors of Korean patients with PMR. Methods We retrospectively evaluated the clinical data of 78 Korean patients with PMR who were treated in 5 tertiary hospitals, and analyzed the therapeutic response and prognostic factors of 39 patients who were followed up at least 1 year. Results Of 78 patients, 51 (65.4%) were women, with a mean age of 68.3±9.2 years. There was no giant cell arteritis in our case series. After 4 weeks of steroid therapy, patient-reported global improvement and ESR response was poor compared to a previous study. Only 57.6% of the patients achieved ≥50% improvement of symptoms and ESR was elevated in 60% of the patients. The rate of relapse (46.1%) was similar to that of previous reports, but only 20.5% of patients reached remission. Relapse occurred mostly in a year, especially between 6-12 months after diagnosis. The rate of relapse and remission at one year of follow-up was 38.4% and 2.5%, respectively. The percentage of females was higher in relapse group (88.9%, p=0.037). Cumulative steroid dose was significantly higher in the relapse group. Independent risk factors for relapse were initial CRP ≥2.5 mg/dl (OR 6.296, p=0.047) and the use of hydroxychloroquine (OR 6.798, p=0.035). Initial steroid dose and tapering speed did not influence prognosis. Conclusions In Korean patients with PMR, baseline clinical characteristics including relapse rate was similar to previous reports, but of special interest, our patients rarely accompanied giant cell arteritis and showed lower remission rate as well as delayed therapeutic response and later occurrence of relapse. More aggressive management will be needed according to the clinical status of patients. References Salvarani C, Cantini F, Boiardi L, Hunder GG (2002) Polymyalgia rheumatica and giant-cell arteritis. N Engl J Med 347:261-271. Lawrence RC, Felson DT, Helmick CG et al (2008) Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part II. Arthritis Rheum 58:26-35. Gonzalez-Gay MA, Agudo M, Martinez-Dubois C, Pompei O, Blanco R (2010) Medical management of polymyalgia rheumatica. Expert Opin Pharmacother 11:1077-1087 Dasgupta B, Borg FA, Hassan N et al (2010) BSR and BHPR guidelines for the management of polymyalgia rheumatica. Rheumatology (Oxford) 49:186-190 Kremers HM, Reinalda MS, Crowson CS, Zinsmeister AR, Hunder GG, Gabriel SE (2005) Relapse in a population based cohort of patients with polymyalgia rheumatica. J Rheumatol 32:65-73. Disclosure of Interest None Declared

Background Stromal cell-derived factor (SDF)-1 (CXCL12) is a chemokine promoting the migration of inflammatory cells into the inflamed synovium in rheumatoid arthritis (RA). The expression of SDF-1 is elevated in serum, synovial fluid, and synovial tissues and it can promote joint destruction by inducing angiogenesis and MMP production. Objectives This study aims to determine the effect and mechanism of SDF-1 on bony destructive process in RA through RANKL regulation from synovial fibroblasts and CD4+ T cells. Methods Synovial fibroblasts were isolated from synovial tissues of RA patients and CD4+ T cells were isolated from PBMC of RA patients. After RA synovial fibroblasts and CD4+ T cells were treated with rhSDF-1, the expression of RANKL mRNA was determined using real-time PCR. After inhibition of pro-inflammatory cytokines or intracellular signal molecules, the change of the SDF-1-induced RANKL expression was analyzed. Results The expression of RANKL mRNA in RA synovial fibroblasts was increased after SDF-1 stimulation in a dose dependent manner. The expression of RANKL mRNA in RA CD4+ T cells was also increased after SDF-1 stimulation in a similar pattern with synovial fibroblasts. After RA synovial fibroblasts were cultured with neutralizing antibodies of TNF-a and IL-6, the expression of RANKL mRNA was decreased in RA synovial fibroblasts. The expression of RANKL mRNA was decreased after CD4+ T cells were cultured with SDF-1 in presence of IL-1b, TNF-a and IL-6. SDF-1-induced RANKL expression was also diminished after inhibition of PI3 kinase, p38 MAP kinase, and JNK. Conclusions This result suggests that SDF-1 could induce RANKL from RA synovial fibroblasts mediated by TNF-a and IL-6. In RA CD4+ T cells, SDF-1-induced RANKL expression is mediated by IL-1b as well as TNF-a and IL-6. Disclosure of Interest None Declared