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Comparable Magnitude (comparable + magnitude)

Distribution by Scientific Domains

Earth and Environmental Science	50%

Selected Abstracts

A comparison of various authoritarianism scales in Belgian Flanders

EUROPEAN JOURNAL OF PERSONALITY, Issue 2 2007
Alain Van Hiel
Abstract The present study compared in a Flemish adult sample (N,=,480) four recently developed authoritarianism scales as well as the widely used Right-Wing Authoritarianism (RWA) scale. Results revealed that all these measures were strongly related and that they showed relationships of comparable magnitude with various indicators of right-wing ideology such as conservatism and racism, as well as with political party preferences. Analyses confirmed the superior fit of a multidimensional model for the scales that are assumed to have an explicit underlying multidimensional structure, but it was also revealed that there was little consensus on what these dimensions exactly mean. Finally, the results indicated serious problems of overlap between cultural conservatism and authoritarianism for some of the scales. Having relied exclusively on an empirical method for comparing the utility of these scales, the use of other criteria for a final assessment of the authoritarianism scales is elaborated upon. Copyright © 2007 John Wiley & Sons, Ltd. [source]

The phosphate site of trehalose phosphorylase from Schizophyllum commune probed by site-directed mutagenesis and chemical rescue studies

FEBS JOURNAL, Issue 5 2008
Christiane Goedl
Schizophyllum commune,,,-trehalose phosphorylase utilizes a glycosyltransferase-like catalytic mechanism to convert its disaccharide substrate into ,- d -glucose 1-phosphate and ,- d -glucose. Recruitment of phosphate by the free enzyme induces ,,,-trehalose binding recognition and promotes the catalytic steps. Like the structurally related glycogen phosphorylase and other retaining glycosyltransferases of fold family GT-B, the trehalose phosphorylase contains an Arg507-XXXX-Lys512 consensus motif (where X is any amino acid) comprising key residues of its putative phosphate-binding sub-site. Loss of wild-type catalytic efficiency for reaction with phosphate (kcat/Km = 21 000 m,1·s,1) was dramatic (,107 -fold) in purified Arg507,Ala (R507A) and Lys512,Ala (K512A) enzymes, reflecting a corresponding change of comparable magnitude in kcat (Arg507) and Km (Lys512). External amine and guanidine derivatives selectively enhanced the activity of the K512A mutant and the R507A mutant respectively. Analysis of the pH dependence of chemical rescue of the K512A mutant by propargylamine suggested that unprotonated amine in combination with H2PO4,, the protonic form of phosphate presumably utilized in enzymatic catalysis, caused restoration of activity. Transition state-like inhibition of the wild-type enzyme A by vanadate in combination with ,,,-trehalose (Ki = 0.4 ,m) was completely disrupted in the R507A mutant but only weakened in the K512A mutant (Ki = 300 ,m). Phosphate (50 mm) enhanced the basal hydrolase activity of the K512A mutant toward ,,,-trehalose by 60% but caused its total suppression in wild-type and R507A enzymes. The results portray differential roles for the side chains of Lys512 and Arg507 in trehalose phosphorylase catalysis, reactant state binding of phosphate and selective stabilization of the transition state respectively. [source]

Daily dataset of 20th-century surface air temperature and precipitation series for the European Climate Assessment

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 12 2002
A. M. G. Klein Tank
Abstract We present a dataset of daily resolution climatic time series that has been compiled for the European Climate Assessment (ECA). As of December 2001, this ECA dataset comprises 199 series of minimum, maximum and/or daily mean temperature and 195 series of daily precipitation amount observed at meteorological stations in Europe and the Middle East. Almost all series cover the standard normal period 1961,90, and about 50% extends back to at least 1925. Part of the dataset (90%) is made available for climate research on CDROM and through the Internet (at http://www.knmi.nl/samenw/eca). A comparison of the ECA dataset with existing gridded datasets, having monthly resolution, shows that correlation coefficients between ECA stations and nearest land grid boxes between 1946 and 1999 are higher than 0.8 for 93% of the temperature series and for 51% of the precipitation series. The overall trends in the ECA dataset are of comparable magnitude to those in the gridded datasets. The potential of the ECA dataset for climate studies is demonstrated in two examples. In the first example, it is shown that the winter (October,March) warming in Europe in the 1976,99 period is accompanied by a positive trend in the number of warm-spell days at most stations, but not by a negative trend in the number of cold-spell days. Instead, the number of cold-spell days increases over Europe. In the second example, it is shown for winter precipitation between 1946 and 1999 that positive trends in the mean amount per wet day prevail in areas that are getting drier and wetter. Because of its daily resolution, the ECA dataset enables a variety of empirical climate studies, including detailed analyses of changes in the occurrence of extremes in relation to changes in mean temperature and total precipitation. Copyright © 2002 Royal Meteorological Society. [source]

Mie simulations as an error source in mineral aerosol radiative forcing calculations

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 623 2007
M. Kahnert
Abstract The role of aerosols remains a major uncertainty for climate and climate change. For the direct radiative forcing by mineral aerosols, the uncertainty in the refractive index m has been regarded as the most important error source, while the impact of aerosol non-sphericity has been considered a minor issue and is neglected in climate models. Here, the errors caused by the spherical particle approximation (SPA) are evaluated by comparing radiative fluxes based on (i) Mie simulations and (ii) laboratory measurements of aerosol optical properties. Furthermore, they are contrasted with the errors related to the uncertainty in the refractive index. These two error sources are found to be of comparable magnitude, although they are strongly dependent on optical depth, surface albedo, and particle size. Thus, our results provide evidence that, contrary to common beliefs, the use of spherical model particles in radiative transfer simulations is probably among the major sources of error in quantifying the climate forcing effect of mineral aerosols. This stems from misrepresentation of the scattering phase function and the asymmetry parameter. Aerosol single-scattering computations based on non-spherical model particles are expected to reduce the shape-related errors and thus significantly improve the accuracy of radiative forcing simulations. Copyright © 2007 Royal Meteorological Society [source]