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Individual Days (individual + day)

Distribution by Scientific Domains
Earth and Environmental Science50%

Selected Abstracts

Efficacy of desloratadine in intermittent allergic rhinitis: a GA2LEN study

ALLERGY, Issue 10 2009
J. Bousquet
Background:, The Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines proposed a classification for allergic rhinitis based on the duration of symptoms (intermittent, persistent) rather than on the time of allergen exposure (seasonal, perennial). There is no placebo-controlled, randomized clinical trial on intermittent allergic rhinitis (IAR) to date. Desloratadine (DL) is recommended for the first-line treatment of seasonal and perennial allergic rhinitis. Objectives:, To assess the efficacy and safety of DL in subjects with IAR based on the ARIA classification. Methods:, Patients over 12 years of age with IAR were assessed over 15 days of treatment with DL 5 mg once daily (n = 276) or placebo (n = 271). The primary endpoint was the AM/PM reflective total 5 symptom score (T5SS). Secondary endpoints included AM/PM instantaneous T5SS and individual symptoms, therapeutic response, symptom severity by visual analogue scale, and quality-of-life. Results:, The mean reduction of AM/PM reflective T5SS was significantly greater with DL than with placebo over 15 days (,3.01 vs,2.13, P < 0.001) and on each individual day (P < 0.05). Mean AM instantaneous T5SS was reduced significantly with DL compared to placebo as early as day 2 (,1.84 vs,0.89; P < 0.001). The therapeutic response and improvement in quality-of-life were significantly greater with DL than with placebo (P < 0.001 for each). The frequency of treatment-related adverse events was low and similar between DL (7.2%) and placebo (7.0%). Conclusions:, This is the first large trial to show that treatment can be effective in IAR. Desloratadine was effective and safe. [source]

Non-linearity and error in modelling soil processes

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2001
T. M. Addiscott
Summary Error in models and their inputs can be propagated to outputs. This is important for modelling soil processes because soil properties used as parameters commonly contain error in the statistical sense, that is, variation. Model error can be assessed by validation procedures, but tests are needed for the propagation of (statistical) error from input to output. Input error interacts with non-linearity in the model such that it contributes to the mean of the output as well as its error. This can lead to seriously incorrect results if input error is ignored when a non-linear model is used, as is demonstrated for the Arrhenius equation. Tests for non-linearity and error propagation are suggested. The simplest test for non-linearity is a graph of the output against the input. This can be supplemented if necessary by testing whether the mean of the output changes as the standard deviation of the input increases. The tests for error propagation examine whether error is suppressed or exaggerated as it is propagated through the model and whether changes in the error in one input influence the propagation of another. Applying these tests to a leaching model with rate and capacity parameters showed differences between the parameters, which emphasized that statements about non-linearity must be for specific inputs and outputs. In particular, simulations of mean annual concentrations of solute in drainage and concentrations on individual days differed greatly in the amount of non-linearity revealed and in the way error was propagated. This result is interpreted in terms of decoherence. [source]

,18O of water vapour, evapotranspiration and the sites of leaf water evaporation in a soybean canopy

PLANT CELL & ENVIRONMENT, Issue 9 2008
LISA R. WELP
ABSTRACT Stable isotopes in water have the potential to diagnose changes in the earth's hydrological budget in response to climate change and land use change. However, there have been few measurements in the vapour phase. Here, we present high-frequency measurements of oxygen isotopic compositions of water vapour (,v) and evapotranspiration (,ET) above a soybean canopy using the tunable diode laser (TDL) technique for the entire 2006 growing season in Minnesota, USA. We observed a large variability in surface ,v from the daily to the seasonal timescales, largely explained by Rayleigh processes, but also influenced by vertical atmospheric mixing, local evapotranspiration (ET) and dew formation. We used ,ET measurements to calculate the isotopic composition at the sites of evaporative enrichment in leaves (,L,e) and compared that with the commonly used steady-state prediction (,L,s). There was generally a good agreement averaged over the season, but larger differences on individual days. We also found that vertical variability in relative humidity and temperature associated with canopy structure must be addressed in canopy-scale leaf water models. Finally, we explored this data set for direct evidence of the Péclet effect. [source]

In situ and remote-sensing measurements of the mean microphysical and optical properties of industrial pollution aerosol during ADRIEX

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue S1 2007
S. R. Osborne
Abstract We present a summary of the principal physical and optical properties of aerosol particles using the FAAM BAE-146 instrumented aircraft during ADRIEX between 27 August and 6 September 2004, augmented by sunphotometer, lidar and satellite retrievals. Observations of anthropogenic aerosol, principally from industrial sources, were concentrated over the northern Adriatic Sea and over the Po Valley close to the aerosol sources. An additional flight was also carried out over the Black Sea to compare east and west European pollution. Measurements show the single-scattering albedo of dry aerosol particles to vary considerably between 0.89 and 0.97 at a wavelength of 0.55 µm, with a campaign mean within the polluted lower free troposphere of 0.92. Although aerosol concentrations varied significantly from day to day and during individual days, the shape of the aerosol size distribution was relatively consistent through the experiment, with no detectable change observed over land and over sea. There is evidence to suggest that the pollution aerosol within the marine boundary layer was younger than that in the elevated layer. Trends in the aerosol volume distribution show consistency with multiple-site AERONET radiometric observations. The aerosol optical depths derived from aircraft measurements show a consistent bias to lower values than both the AERONET and lidar ground-based radiometric observations, differences which can be explained by local variations in the aerosol column loading and by some aircraft instrumental artefacts. Retrievals of the aerosol optical depth and fine-mode (<0.5 µm radius) fraction contribution to the optical depth using MODIS data from the Terra and Aqua satellites show a reasonable level of agreement with the AERONET and aircraft measurements. © Crown Copyright 2007. Reproduced with the permission of the Controller of HMSO. Published by John Wiley & Sons, Ltd [source]