The effects of majority requirements, selectorate composition and uncertainty in indirect presidential elections: The case of Estonia

This article assesses the effects of common features in the indirect election of presidents in parliamentary republics. In particular, it examines the influence of majority requirements, selectorate composition and uncertainty on party strategies, using Estonia (1996-2016) as a crucial case for analysis. The analysis demonstrates that the lack of a plurality run-off effectively eliminated incentives for inter-party cooperation and strategic voting. It furthermore shows that shifts in the partisan composition and control of the selectorate from parliament to electoral college provided considerable opportunities for agenda manipulation. Subsequently, results only rarely reflected the parliamentary balance of power. Last, although overall indicators suggest greater congruence between parliament and electoral college over time, this proliferated rather than reduced parties’ uncertainty over the electoral outcome as non parliamentary electors voted based on local interests and acted independently from national party leaders

Metastable Strings in Abelian Higgs Models Embedded in Non-Abelian Theories: Calculating the Decay Rate

We study the fate of U(1) strings embedded in a non-Abelian gauge theory with a hierarchical pattern of the symmetry breaking: G->U(1) at V->nothing at v, V>>v. While in the low-energy limit the Abrikosov-Nielsen-Olesen string (flux tube) is perfectly stable, being considered in the full theory it is metastable. We consider the simplest example: the magnetic flux tubes in the SU(2) gauge theory with adjoint and fundamental scalars. First, the adjoint scalar develops a vacuum expectation value V breaking SU(2) down to U(1). Then, at a much lower scale, the fundamental scalar (quark) develops a vacuum expectation value v creating the Abrikosov-Nielsen-Olesen string. (We also consider an alternative scenario in which the second breaking, U(1)->nothing, is due to an adjoint field.) We suggest an illustrative ansatz describing an "unwinding" in SU(2) of the winding inherent to the Abrikosov-Nielsen-Olesen strings in U(1). This ansatz determines an effective 2D theory for the unstable mode on the string world-sheet. We calculate the decay rate (per unit length of the string) in this ansatz and then derive a general formula. The decay rate is exponentially suppressed. The suppressing exponent is proportional to the ratio of the monopole mass squared to the string tension, which is quite natural in view of the string breaking through the monopole-antimonopole pair production. We compare our result with the one given by Schwinger's formula dualized for describing the monopole-antimonopole pair production in the magnetic field.Comment: Significant revisions: 2 sections and 2 figures added, references added, the report number changed; 2 sections revised; Latex, 35 pages, 7 figure

Crystal structure of pseudojohannite, with a revised formula, Cu(3)(OH)(2)[(UO(2))(4)O(4)SO(4))(2)](H(2)O)(12)

The crystal structure of pseudojohannite from White Canyon, Utah, was solved by charge-flipping from single-crystal X-ray diffraction data and refined to an Robs = 0.0347, based on 2664 observed reflections. Pseudojohannite from White Canyon is triclinic, P1̄, with a = 8.6744(4), b = 8.8692(4), c = 10.0090(5) Å, α = 72.105(4)°, β = 70.544(4)°, γ = 76.035(4)°, and V = 682.61(5) ų, with Z = 1 and chemical formula Cu₃(OH)₂[(UO₂)₄O₄(SO₄)₂](H₂O)₁₂. The crystal structure of pseudojohannite is built up from sheets of zippeite topology that do not contain any OH groups; these sheets are identical to those found in zippeites containing Mg²+, Co²+, and Zn2+. The two Cu²+ sites in pseudojohannite are [5]- and [6]-coordinated by H₂O molecules and OH groups. The crystal structure of the pseudojohannite holotype specimen from Jáchymov was refined using Rietveld refinement of high-resolution powder diffraction data. Results indicate that the crystal structures of pseudojohannite from White Canyon and Jáchymov are identical.J. Plášil, K. Fejfarová, K.S. Wallwork, M. Dušek, R. Škoda, J. Sejkora, J. Čejka, F. Veselovský, J. Hloušek, N. Meisser, J. Brugge

Crystal structure and formula revision of deliensite, Fe[(UO2)2(SO4)2(OH)2](H2O)7

AbstractThe crystal structure of deliensite, Fe[(UO2)2(SO4)2(OH)2](H2O)7, was solved by direct methods and refined toR1= 6.24% for 5211 unique observed reflections [Iobs&gt; 3σ(I)], on a crystal that was found to consist of rotational and inversion (merohedral) twins, from Jeroným mine, Abertamy in the Czech Republic. The presence of four twin domains was taken into account in the refinement. The structure is orthorhombic, space groupPnn2, with unit-cell parametersa= 15.8514(9),b= 16.2478(7),c= 6.8943(3) Å,V= 1775.6(1) Å3andZ= 4. The crystal structure of deliensite contains uranyl-sulfate sheets with a phosphuranylite topology, consisting of dimers of edge-sharing uranyl pentagonal bipyramids linked by corner-sharing with sulfate tetrahedra. The sheets lie in the (100) plane and are decorated by [Fe2+O(H2O)5] octahedra; two weakly bonded H2O molecules are present in the interlayer. The [Fe2+O(H2O)5] octahedron is linked directly to the sheet via the uranyl oxygen atom. Adjacent sheets are linked by hydrogen bonds only. The sheet topology and geometrical isomerism is discussed and a comparison of the composition obtained from electron-probe microanalysis, powder-diffraction data, Raman and infrared spectra of deliensite samples from Mas d'Alary, Lodève, France; L'Ecarpière mine, Gétigné, France; and several localities at Jáchymov, Western Bohemia, Czech Republic is made.</jats:p