North American Boreal Wildfire and Anthropogenic Emissin Impacts in the Lower Free Troposphere over the North Atlantic Region: observations at the PICO-NARE station

AGU Fall Meeting. San Francisco, California, 11-15 December 2006.We present analyses of CO, O3, nitrogen oxides (NOx and NOy) and aerosol black carbon (BC) measurements made in the lower free troposphere (FT) over the North Atlantic region during summers 2004 (ICARTT period) and 2005

Late summer changes in burning conditions in the boreal regions and their implications for NO x and CO emissions from boreal fires

Copyright © 2008 American Geophysical Union. All Rights Reserved.Building emission inventories for the fires in boreal regions remains a challenging task with significant uncertainties in the methods used. In this work, we assess the impact of seasonal trends in fuel consumption and flaming/smoldering ratios on emissions of species dominated by flaming combustion (e.g., NO x ) and species dominated by smoldering combustion (e.g., CO). This is accomplished using measurements of CO and NO y at the free tropospheric Pico Mountain observatory in the central North Atlantic during the active boreal fire seasons of 2004 and 2005. ΔNO y /ΔCO enhancement ratios in aged fire plumes had higher values in June-July (7.3 × 10−3 mol mol−1) relative to the values in August-September (2.8 × 10−3 mol mol−1), indicating that NO x /CO emission ratios declined significantly as the fire season progressed. This is consistent with our understanding that an increased amount of fuel is consumed via smoldering combustion during late summer, as deeper burning of the drying organic soil layer occurs. A major growth in fuel consumption per unit area is also expected, due to deeper burning. Emissions of CO and NO x from North American boreal fires were estimated using the Boreal Wildland Fire Emissions Model, and their long-range transport to the sampling site was modeled using FLEXPART. These simulations were generally consistent with the observations, but the modeled seasonal decline in the ΔNO y /ΔCO enhancement ratio was less than observed. Comparisons using alternative fire emission injection height scenarios suggest that plumes with the highest CO levels at the observatory were lofted well above the boundary layer, likely as a result of intense crown fires

Impacts of anthropogenic and boreal fire emissions in the central North Atlantic lower free troposphere: summertime observations at the PICO-NARE observatory.

ICARTT 2004 Data Workshop. Durham, New Hampshire, August 9-12, 2005.We present measurements of CO, O3, aerosol Black Carbon (BC) made over the central North Atlantic lower Free Troposphere (FT) during the summers of 2001-2004 along with measurements of nitrogen oxides (NOx and NOy) made during the summer of 2004 (ICARTT period) and non-methane hydrocarbons (NMHCs) made during the winter 2004-spring 2005

Large-scale impacts of anthropogenic and boreal fire emissions apparent in multi-year free tropospheric observations in the Azores.

Gordon conference - Atmospheric Chemistry. Big Sky, Montana, September 4-9 2005.Pico Mountain in the Azores Islands provides an ideal location for studies of the central N. Atlantic lower free troposphere. The PICO-NARE station has operated there since summer 2001. Here, we present key findings from summertime measurements, during 2001-2004. Main Findings: Anthropogenic and boreal wildfire emissions dominate variations in CO and have major impacts on O3, nitrogen oxides, non-methane hydrocarbons (NMHCs) and black carbon

Current Trends in Treatment for Acid-Dependent Diseases: Clinical Efficacy and Safety of Rabeprazole

Aim. A comparative review of the rabeprazole properties vs. other PPIs, its efficacy and safety in treatment for aciddependent diseases.Key points. Rabeprazole provides a rapid proton pump blockade in parietal cells due to its high dissociation constant (pKa). A lower rabeprazole metabolic dependence on cytochrome P-450 enzyme system renders its antisecretory effect predictable and reduces the risk of interactions with other drugs metabolised through this system. A faster antisecretory effect and higher acid-suppressive activity of rabeprazole determine its better clinical efficacy in treatment for such acid-dependent diseases as gastroesophageal reflux disease and peptic ulcer. This makes rabeprazole (Pariet) a preferred drug in course and maintenance therapies for acid-dependent diseases, as well as in H. pylori eradication.Conclusion. The rabeprazole properties of high acid suppression potential, persistent antisecretory effect from first day of therapy, non-enzymatic metabolism and pleiotropic action determine its high efficacy in treatment for a wide range of acid-dependent diseases at a minimal risk of drug interaction

Investigating organic aerosol loading in the remote marine environment

Aerosol loading in the marine environment is investigated using aerosol composition measurements from several research ship campaigns (ICEALOT, MAP, RHaMBLe, VOCALS and OOMPH), observations of total AOD column from satellite (MODIS) and ship-based instruments (Maritime Aerosol Network, MAN), and a global chemical transport model (GEOS-Chem). This work represents the most comprehensive evaluation of oceanic OM emission inventories to date, by employing aerosol composition measurements obtained from campaigns with wide spatial and temporal coverage. The model underestimates AOD over the remote ocean on average by 0.02 (21 %), compared to satellite observations, but provides an unbiased simulation of ground-based Maritime Aerosol Network (MAN) observations. Comparison with cruise data demonstrates that the GEOS-Chem simulation of marine sulfate, with the mean observed values ranging between 0.22 μg m−3 and 1.34 μg m−3, is generally unbiased, however surface organic matter (OM) concentrations, with the mean observed concentrations between 0.07 μg m−3 and 0.77 μg m−3, are underestimated by a factor of 2–5 for the standard model run. Addition of a sub-micron marine OM source of approximately 9 TgC yr−1 brings the model into agreement with the ship-based measurements, however this additional OM source does not explain the model underestimate of marine AOD. The model underestimate of marine AOD is therefore likely the result of a combination of satellite retrieval bias and a missing marine aerosol source (which exhibits a different spatial pattern than existing aerosol in the model)

ASSESSMENT OF SURVIVAL OF ZYGOMATIC IMPLANTS AND ROOT DENTAL IMPLANTS

Currently, dental implantation has taken a leading position in the complex treatment of various dental diseases as the main and the most progressive method of restoring the quality of life of patients. Work is devoted to studying of implants survival at 29 patients of specialized unit of multi-speciality hospital. 68 zygomatic implants and 137 root dental implants were set up to these patients. Implants were set up to get stomatologic rehabilitation of patients with the acquired adentia of jaws. The comparative assessment of survival of zygomatic and dental implants was carried out, the period of observation was 36 months. The assessment of survival of root dental implants at all patients operated for the reporting period of time was carried also out

Regional and hemispheric impacts of anthropogenic and biomass burning emissions on summertime CO and O3 in the North Atlantic lower free troposphere

Copyright © 2004 American Geophysical Union. All Rights Reserved.We report summertime measurements of CO and O3 obtained during 2001–2003 at the PICO-NARE mountaintop station in the Azores. Frequent events of elevated CO mixing ratios were observed. On the basis of backward trajectories arriving in the free troposphere and global simulations of biomass burning plumes, we attribute nearly all these events to North American pollution outflow and long-range transport of biomass burning emissions. There was a high degree of interannual variability in CO levels: median [CO] ranged from 65 ppbv in 2001 to 104 ppbv in 2003. The highest concentrations were associated with transport of Siberian fire emissions during summer 2003, when Siberian fire activity was unusually high. Ozone mixing ratios also increased (by up to ∼30 ppbv) during the fire events. These findings demonstrate the significant hemispheric scale impact that biomass burning events have on background CO and O3 levels. O3 enhancements of similar magnitude were also observed in North American pollution outflow. O3 and CO were correlated during North American outflow events, with a slope averaging 1.0 (d[O3]/d[CO], ppbv/ppbv) when no fire impact was present. This slope is more than 80% larger than early 1990s observations made in the eastern United States and nearshore outflow region, even after accounting for declining U.S. CO emissions and for CO loss during transport to the Azores, and is not consistent with simple dilution of U.S. outflow with marine background air. We conclude that a significantly larger amount of O3 production occurred in the air sampled during this study, and we suggest several potential reasons for this, each of which could imply potentially significant shortcomings in current estimates of the hemispheric impact of North American emissions on tropospheric ozone and should be evaluated in future studies

Assessment of source contributions to seasonal vegetative exposure to ozone in the U.S.

W126 is a cumulative ozone exposure index based on sigmoidally weighted daytime ozone concentrations used to evaluate the impacts of ozone on vegetation. We quantify W126 in the U.S. in the absence of North American anthropogenic emissions (North American background or “NAB”) using three regional or global chemical transport models for May–July 2010. All models overestimate W126 in the eastern U.S. due to a persistent bias in daytime ozone, while the models are relatively unbiased in California and the Intermountain West. Substantial difference in the magnitude and spatial and temporal variability of the estimates of W126 NAB between models supports the need for a multimodel approach. While the average NAB contribution to daytime ozone in the Intermountain West is 64–78%, the average W126 NAB is only 9–27% of current levels, owing to the weight given to high O3 concentrations in W126. Based on a three-model mean, NAB explains ~30% of the daily variability in the W126 daily index in the Intermountain West. Adjoint sensitivity analysis shows that nationwide W126 is influenced most by NOx emissions from anthropogenic (58% of the total sensitivity) and natural (25%) sources followed by nonmethane volatile organic compounds (10%) and CO (7%). Most of the influence of anthropogenic NOx comes from the U.S. (80%), followed by Canada (9%), Mexico (4%), and China (3%). Thus, long-range transport of pollution has a relatively small impact on W126 in the U.S., and domestic emissions control should be effective for reducing W126 levels

Определение хлорсодержащих соединений в дезинфицирующих средствах с использованием ионообменной хроматографии

Objectives. To develop a method for the determination of hypochlorite, chloride, chlorite, chlorate, and perchlorate ions in solution; to determine the limits of detection and quantitation for ClO−, Cl−, ClO2−, ClO3−, and ClO4− ions; to evaluate the applicability of the developed method and its suitability for disinfectant analysis.Methods. Ionic chromatography using a conductometric detection system in isocratic elution mode.Results. The method developed for chromatographic determination of chlorine-containing ions can be used to quantify the content of hypochlorite, chloride, chlorite, chlorate, and perchlorate ions. In isocratic elution mode at 7.5 mM NaOH and a flow rate of 0.4 mL/min, the content of chlorine-containing ions can be determined with high sensitivity. The presented method does not require the use of expensive equipment for the ultrasensitive analysis of the studied compounds.Conclusions. A novel method for the simultaneous determination of hypochlorite, chloride, chlorite, chlorate, and perchlorate ions in case of their combined presence is proposed. The technique can be used to carry out routine control of the content of these disinfectant components during use, increasing their effectiveness at the same time as managing associated toxicological risks.Цели. Разработать методику определения гипохлорит-, хлорид-, хлорит-, хлорати перхлорат-ионов при их совместном присутствии в дезинфицирующих средствах. Определить пределы обнаружения и пределы количественного определения ионов ClO−, Cl−, ClO2−, ClO3−, ClO4−. Провести расчеты валидационных параметров разработанной методики, а также оценить ее пригодность для анализа дезинфицирующих средств.Методы. Ионообменная хроматография с системой кондуктометрического детектирования в изократическом режиме элюирования.Результаты. Новая методика хроматографического определения хлорсодержащих ионов позволяет количественно оценить содержание гипохлорит-, хлорид-, хлорит-, хлорат- и перхлорат-ионов при их одновременном нахождении в модельном растворе и в дезинфицирующих средствах. Изократический режим элюирования 7.5 мМ NaOH при скорости движения потока 0.4 мл/мин позволяет с высокой чувствительностью определять ионы, содержащие атом хлора. Разработанная методика не требует использования дорогостоящего оборудования, необходимого для сверхчувствительного анализа исследуемых соединений.Выводы. Впервые предложена методика определения гипохлорит-, хлорид-, хлорит-, хлорат- и перхлорат-ионов при совместном присутствии. Ожидается, что разработанная методика позволит проводить рутинный контроль содержания этих компонентов в дезинфицирующих средствах при их практическом использовании, что приведет к повышению эффективности применения дезинфектантов на их основе и снижению возможных токсикологических рисков