Ideal Case (ideal + case)

Distribution by Scientific Domains

Selected Abstracts

International Regimes, Domestic Veto-Players, and Capital Controls Policy Stability

Scott L. Kastner
States' decisions about regulating international capital movements are shaped in part by institutions and partisanship at the domestic level, but the effects of domestic-level variables are themselves contingent on the constraints imposed by the international system. We amend the veto-players hypothesis to account for the effects of international regimes on the political influence of domestic players in state decision-making. The history of changes in international financial regulations over the past four decades provides an ideal case to study the interaction of international regimes and domestic decision-making systems. We create a data set of all capital controls policy changes that 19 OECD parliamentary democracies made during the years 1951,1998. Using these new data, we find that states with a higher number of veto-player parties in government enact fewer capital controls policy changes. Furthermore, ideologically right-of-center governments in these industrialized countries are more likely than others to enact capital controls liberalizations. We also find, however, that the independent effects of these domestic-level variables disappear after the mid-1980s, when the systemic constraints imposed on individual states increased substantially. [source]

A toolkit for the characterization of CCD cameras for transmission electron microscopy

M. Vulovic
Charge-coupled devices (CCD) are nowadays commonly utilized in transmission electron microscopy (TEM) for applications in life sciences. Direct access to digitized images has revolutionized the use of electron microscopy, sparking developments such as automated collection of tomographic data, focal series, random conical tilt pairs and ultralarge single-particle data sets. Nevertheless, for ultrahigh-resolution work photographic plates are often still preferred. In the ideal case, the quality of the recorded image of a vitrified biological sample would solely be determined by the counting statistics of the limited electron dose the sample can withstand before beam-induced alterations dominate. Unfortunately, the image is degraded by the non-ideal point-spread function of the detector, as a result of a scintillator coupled by fibre optics to a CCD, and the addition of several inherent noise components. Different detector manufacturers provide different types of figures of merit when advertising the quality of their detector. It is hard for most laboratories to verify whether all of the anticipated specifications are met. In this report, a set of algorithms is presented to characterize on-axis slow-scan large-area CCD-based TEM detectors. These tools have been added to a publicly available image-processing toolbox for MATLAB. Three in-house CCD cameras were carefully characterized, yielding, among others, statistics for hot and bad pixels, the modulation transfer function, the conversion factor, the effective gain and the detective quantum efficiency. These statistics will aid data-collection strategy programs and provide prior information for quantitative imaging. The relative performance of the characterized detectors is discussed and a comparison is made with similar detectors that are used in the field of X-ray crystallography. [source]

How Pervasive are Euro-Politics?

Effects of EU Membership on a New Member State
While the consequences of becoming an EU Member State for national policies are usually the core concern of pre-membership debates and of post-accession assessments, studies of the effects of European integration on the political systems of the Member States have so far been less numerous. Among the new EU members, which are ideal cases for studying domestic accession effects, Austria is a particularly challenging case in terms of top-down impact on the national political system. A number of specific precautions were taken in order to protect typical features of the national political system (notably the traditional roles of parliament, Länder and social partners) from being eroded in the multi-level system. The basic research question of this article is whether or not these measures were actually successful. How ,sticky' is the EU upon closer inspection, i.e. how pervasive are its effects on adverse national structures? Can national measures, even at the constitutional level, outweigh specific consequences of participating in Euro-politics? If not 9as the Austrian case indicates), why not? The conclusions distinguish specific Austrian variables from generalizable ones and discuss the findings in the light of the existing literature. [source]

Telomerization of acrylic acid with mercaptans: Part 2.

Kinetics of the synthesis of star-shaped macromolecules of acrylic acid
Abstract The telomerization of acrylic acid with a polyfunctional transfer agent initiated by 2,2,-azobisisobutyronitrile, was first investigated in an organic medium (THF) at 65,°C. Transfer constants (CT) for three mercaptans, ethylene glycol bisthioglycolate, trimethylolpropane tris(2-mercaptoacetate) and pentaerythritol tetrakis(3-mercaptopropionate) of about 6.1, 6.3 and 7.3, respectively, were determined. From these results, it followed that a well-defined star poly(acrylic acid) could not be synthesized via telomerization of acrylic acid in THF. Nevertheless, the same study was performed with the tetrafunctional transfer agent in water/THF mixtures. This work emphasized that the nature of the solvent plays an important role in determining the transfer constant. Thus, the value of CT for the tetrafunctional transfer agent decreased from 7.3 in THF to 1, the ,ideal' case for telomerization (CT,,,1), for the mixture of solvents water/THF (80%, 20%, v/v). With this route, it seems that acrylic acid star-shaped macromolecules could be synthesized via telomerization. © 2001 Society of Chemical Industry [source]