			Home About us Contact

Necessary Requirement (necessary + requirement)

Distribution by Scientific Domains

Chemistry	40%

Selected Abstracts

Is EMDR an exposure therapy?

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 1 2002
A review of trauma protocols
This article presents the well established theoretical base and clinical practice of exposure therapy for trauma. Necessary requirements for positive treatment results and contraindicated procedures are reviewed. EMDR is contrasted with these requirements and procedures. By the definitions and clinical practice of exposure therapy, the classification of EMDR poses some problems. As seen from the exposure therapy paradigm, its lack of physiological habituation and use of spontaneous association should result in negligible or negative effects rather than the well researched positive outcomes. Possible reasons for the effectiveness of EMDR are discussed, ranging from the fundamental nature of trauma reactions to the nonexposure mechanisms utilized in information processing models. © 2002 John Wiley & Sons, Inc. J Clin Psychol 58: 43,59, 2002. [source]

Iminohydroxamato Early and Late Transition Metal Halide Complexes , New Precatalysts for Aluminoxane-Cocatalyzed Olefin Insertion Polymerization

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2004
Alexander Krajete
Abstract We report on new families of non-metallocene metal precatalysts for olefin polymerization with titanium, zirconium, vanadium and nickel as the active metal sites. The novel ligand design concept is based on iminohydroxamic acids and their derivatives as the principal chelating units. Various anionic and neutral [N,O] and [N,N] ligand systems are easily accessible by a modular synthetic sequence of imidoyl chlorides with substituted hydroxylamines or hydrazines, respectively. Steric protection of the metal coordination site, a necessary requirement for suppression of chain termination pathways of non-metallocene catalysts, is brought about by bulky aryl substituents on the imino nitrogen atoms. Crystal structures of some of the hydroxamato ligands reveal interesting intermolecular hydrogen-bridged structures, whereas in the solid-state structure of one titanium precatalyst a five-membered chelate was observed, in line with the design principle of these systems. Preliminary ethylene polymerization studies with methylaluminoxane-activated metal complexes (M = Ti, Zr, V, Ni) show that the most active systems are [N,O]NiBr2 catalysts containing neutral O -alkyl iminohydroxamate ligands. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source]

Abolishing the Tax-Free Threshold in Australia: Simulating Alternative Reforms,

FISCAL STUDIES, Issue 2 2009
John Creedy
H24; H31 Abstract This paper examines the role of the tax-free income tax threshold in a complex tax and transfer system consisting of a range of taxes and benefits, each with its own taper rates and thresholds. Considering a tax and benefit system with benefit taper rates whereby some benefits are received by income groups other than those at the bottom of the distribution, it is suggested that a tax-free threshold is not a necessary requirement to achieve redistribution. Four alternative policy changes, each involving the elimination of the tax-free threshold in Australia and designed to achieve approximate revenue neutrality, were examined using the Melbourne Institute Tax and Transfer Simulator. A range of implications were examined, including labour supply responses to tax changes and the effects of policy changes on inequality and social welfare. The results demonstrate that it is possible to eliminate the tax-free threshold under approximate overall revenue and distribution neutrality, but that it is impossible to improve labour supply incentives at the same time. In order to achieve improved incentives, either revenue or distribution neutrality has to be sacrificed. [source]

The interdependence of wavelength, redundancy and dose in sulfur SAD experiments

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 12 2008
Michele Cianci
In the last decade, the popularity of sulfur SAD anomalous dispersion experiments has spread rapidly among synchrotron users as a quick and streamlined way of solving the phase problem in macromolecular crystallography. On beamline 10 at SRS (Daresbury Laboratory, UK), a versatile design has allowed test data sets to be collected at six wavelengths between 0.979 and 2.290,Å in order to evaluate the importance and the interdependence of experimental variables such as the Bijvoet ratio, wavelength, resolution limit, data redundancy and absorbed X-ray dose in the sample per data set. All the samples used in the experiments were high-quality hen egg-white lysozyme crystals. X-radiation damage was found to affect disulfide bridges after the crystals had been given a total dose of 0.20 × 107,Gy. However, with such a total dose, it was still possible in all cases to find a strategy to collect data sets to determine the sulfur substructure and produce good-quality phases by choosing an optimum combination of wavelength, exposure time and redundancy. A ,|,ano|/,(,ano), greater than 1.5 for all resolution shells was a necessary requirement for successful sulfur SAD substructure location. Provided this is achieved, it seems possible to find an optimum compromise between wavelength, redundancy and dose to provide phasing information. The choice of the wavelength should then follow the sample composition and the diffracting properties of the crystal. For strongly diffracting crystals, wavelengths equal or shorter than 1.540,Å can be selected to capture the available data (provided the Bijvoet ratio is reasonable), while a longer wavelength, to gain as high a Bijvoet ratio as possible, must be used for more weakly diffracting crystals. These results suggest that an approach to a sulfur SAD experiment based on a complete description of the crystal system and the instrument for data collection is useful. [source]

The Concept of Law and Its Conceptions

RATIO JURIS, Issue 2 2006
PETER KOLLER
With this aim in view, I shall begin with a few remarks on concept formation and name a list of necessary requirements on an appropriate concept of law. On this basis, I intend to discuss a number of contemporary legal theories in view to their respective interpretations of the concept of law. Finally, I want to propose a definition of law that not only satisfies the requirements of the concept of law, but is also general enough to be compatible with both camps of legal thinking. [source]