Alpha-decay Rates of Yb and Gd in Solar Neutrino Detectors

The $\alpha$-decay rates for the nuclides $^{168,170,171,172,173,174,176}$Yb and $^{148,150,152,154}$Gd have been estimated from transmission probabilities in a systematic $\alpha$-nucleus potential and from an improved fit to $\alpha$-decay rates in the rare-earth mass region. Whereas ${\alpha}$-decay of $^{152}$Gd in natural gadolinium is a severe obstacle for the use of gadolinium as a low-energy solar-neutrino detector, we show that ${\alpha}$-decay does not contribute significantly to the background in a ytterbium detector. An extremely long ${\alpha}$-decay lifetime of $^{168}$Yb is obtained from calculation, which may be close to the sensitivity limit in a low-background solar neutrino detector.Comment: 12 pages, 1 figure; An author name was correcte

Behind the cube rule: implications of and evidence against a fractal electoral geography

An earlier version of this paper was issued as Discussion Papers in Economics, 01/03. The definitive, peer-reviewed and edited version of this article is published in Environment and Planning A, August 2003 35(8) p. 1405-1414In 1909 Parker Smith showed that the ratio of seats won by the two major parties in Britain was close to the cube of the ratio of their votes. Taagepera and Shugart argue, wrongly, that a fractal electoral map implies this. In fact their premises imply that the seats’ ratio will be the votes’ ratio to the power of , not 3. However, in the six countries we examine, the figure is between 2 and 3. This implies that the electoral map is nonfractal, political allegiances becoming less ‘clustered’ as you move from a macro to a micro scale. Taking the U.K., we ask if this is due to the geographical pattern of income distribution, and find that this is even further away from fractality than is voting. This fits the well known ‘neighborhood effect’ whereby poor (rich) people in rich (poor) constituencies vote as if richer (poorer) than they really are

Why Northern Ireland’s Institutions Need Stability

© The Author(s). Published by Government and Opposition Limited and Cambridge University Press 2014. Northern Ireland's consociational institutions were reviewed by a committee of its Assembly in 2012-13. The arguments of both critics and exponents of the arrangements are of general interest to scholars of comparative politics, power-sharing and constitutional design. The authors of this article review the debates and evidence on the d'Hondt rule of executive formation, political designation, the likely impact of changing district magnitudes for assembly elections, and existing patterns of opposition and accountability. They evaluate the scholarly, political and legal literature before commending the merits of maintaining the existing system, including the rules under which the system might be modified in future.Link_to_subscribed_fulltex

Who stands in the way of women? Open vs. closed lists and candidate gender in Estonia

The literature on women's descriptive representation has looked at the debate on open and closed lists as a choice between electoral systems. This article instead focuses on whether voters or the parties are biased against female candidates. Using data from six Estonian elections, the article finds that voters are not consistently biased against female candidates and open lists do not necessarily decrease women's representation. However, unknown and non-incumbent female candidates fare significantly worse than similar men. The analysis also shows that parties do not place women in electable positions on closed lists, and closed lists do not improve women's representation

On the alpha activity of natural tungsten isotopes

The indication for the alpha decay of 180-W with a half-life T1/2=1.1+0.8-0.4(stat)+-0.3(syst)x10^18 yr has been observed for the first time with the help of the super-low background 116-CdWO_4 crystal scintillators. In conservative approach the lower limit on half-life of 180-W has been established as T1/2>0.7x10^18 yr at 90% C.L. Besides, new T1/2 bounds were set for alpha decay of 182-W, 183-W, 184-W and 186-W at the level of 10^20 yr.Comment: 16 pages, 8 figures, accepted in Phys. Rev.

Regulation of Op18 during Spindle Assembly in Xenopus Egg Extracts

Oncoprotein 18 (Op18) is a microtubule-destabilizing protein that is negatively regulated by phosphorylation. To evaluate the role of the three Op18 phosphorylation sites in Xenopus (Ser 16, 25, and 39), we added wild-type Op18, a nonphosphorylatable triple Ser to Ala mutant (Op18-AAA), and to mimic phosphorylation, a triple Ser to Glu mutant (Op18-EEE) to egg extracts and monitored spindle assembly. Op18-AAA dramatically decreased microtubule length and density, while Op18-EEE did not significantly affect spindle microtubules. Affinity chromatography with these proteins revealed that the microtubule-destabilizing activity correlated with the ability of Op18 to bind tubulin. Since hyperphosphorylation of Op18 is observed upon addition of mitotic chromatin to extracts, we reasoned that chromatin-associated proteins might play a role in Op18 regulation. We have performed a preliminary characterization of the chromatin proteins recruited to DNA beads, and identified the Xenopus polo-like kinase Plx1 as a chromatin-associated kinase that regulates Op18 phosphorylation. Depletion of Plx1 inhibits chromatin-induced Op18 hyperphosphorylation and spindle assembly in extracts. Therefore, Plx1 may promote microtubule stabilization and spindle assembly by inhibiting Op18

Predicting Mean Cabinet Duration on the Basis of Electoral System

We join two existing logical models and tests the resulting predictions of mean cabinet duration (C). One of these models predicts C based on effective number of parties (N): C=k/N2 , where k is found to be around 42 years. The other predicts N on the basis of number of seats in the assembly (S) and district magnitude (M). The new combined model leads to a prediction for the mean cabinet duration in terms of these two institutional factors: C=42 years/(MS)1/3. Three quarters of the actual mean durations agree with the prediction within a factor of 2. For the purposes of institutional engineering, the model predicts that doubling the district magnitude would reduce the mean cabinet duration by 21 percent ceteris paribus

Party finance reform as constitutional engineering? The effectiveness and unintended consequences of party finance reform in France and Britain

In both Britain and France, party funding was traditionally characterized by a laissez faire approach and a conspicuous lack of regulation. In France, this was tantamount to a 'legislative vacuum'. In the last two decades, however, both countries have sought to fundamentally reform their political finance regulation regimes. This prompted, in Britain, the Political Parties, Elections and Referendums Act 2000, and in France a bout of 'legislative incontinence' — profoundly transforming the political finance regime between 1988 and 1995. This article seeks to explore and compare the impacts of the reforms in each country in a bid to explain the unintended consequences of the alternative paths taken and the effectiveness of the new party finance regime in each country. It finds that constitutional engineering through party finance reform is a singularly inexact science, largely due to the imperfect nature of information, the limited predictability of cause and effect, and the constraining influence of non-party actors, such as the Constitutional Council in France, and the Electoral Commission in Britain

Party control, party competition and public service performance

publication-status: Acceptedtypes: ArticleThis article assesses party effects on the performance of public services. A policy-seeking model, hypothesizing that left and right party control affects performance, and an instrumental model, where all parties strive to raise performance, are presented. The framework also suggests a mixed model in which party effects are contingent on party competition, with parties raising performance as increasing party competition places their control of government at increasing risk. These models are tested against panel data on English local governments’ party control and public service performance. The results question the traditional account of left and right parties, showing a positive relationship between rightwing party control and performance that is contingent on a sufficiently high level of party competition. The findings suggest left–right models should be reframed for the contemporary context

Basic kinetic wealth-exchange models: common features and open problems

We review the basic kinetic wealth-exchange models of Angle [J. Angle, Social Forces 65 (1986) 293; J. Math. Sociol. 26 (2002) 217], Bennati [E. Bennati, Rivista Internazionale di Scienze Economiche e Commerciali 35 (1988) 735], Chakraborti and Chakrabarti [A. Chakraborti, B. K. Chakrabarti, Eur. Phys. J. B 17 (2000) 167], and of Dragulescu and Yakovenko [A. Dragulescu, V. M. Yakovenko, Eur. Phys. J. B 17 (2000) 723]. Analytical fitting forms for the equilibrium wealth distributions are proposed. The influence of heterogeneity is investigated, the appearance of the fat tail in the wealth distribution and the relaxation to equilibrium are discussed. A unified reformulation of the models considered is suggested.Comment: Updated version; 9 pages, 5 figures, 2 table