372 research outputs found
Does intra-party democracy affect levels of trust in parties?:the cases of Belgium and Israel
Previous research has shown a steady decline of citizen's political trus and growing skepticism towards key institutions of representative democr acy. Political parties, which perform the crucial role of linking citizens to the political system, are in the eye of the storm: citizens are generally more distrusting towards parties than other social and political institutions. The relevant literature mentions that parties often implement intra-party democratization to remedy party distrust. This article examines whether democratic candidate selection processes actually affect party trust among voters. The analysis is based on the cases of Belgium and Israel, where politicians made a strong case for intra-party democracy in recent history. The results indicate that, while inclusive selectorates indeed increase trust levels, decentralization decreases trust towards parties in both countries
Tannakian duality for Anderson-Drinfeld motives and algebraic independence of Carlitz logarithms
We develop a theory of Tannakian Galois groups for t-motives and relate this
to the theory of Frobenius semilinear difference equations. We show that the
transcendence degree of the period matrix associated to a given t-motive is
equal to the dimension of its Galois group. Using this result we prove that
Carlitz logarithms of algebraic functions that are linearly independent over
the rational function field are algebraically independent.Comment: 39 page
Non integrability of a self-gravitating Riemann liquid ellipsoid
We prove that the motion of a triaxial Riemann ellipsoid of homogeneous
liquid without angular momentum does not possess an additional first integral
which is meromorphic in position, impulsions, and the elliptic functions which
appear in the potential, and thus is not integrable. We prove moreover that
this system is not integrable even on a fixed energy level hypersurface.Comment: 14 pages, 8 reference
Association of Rhegmatogenous Retinal Detachment Incidence With Myopia Prevalence in the Netherlands
Importance The incidence of rhegmatogenous retinal detachment (RRD) is partly determined by its risk factors, such as age, sex, cataract surgery, and myopia. Changes in the prevalence of these risk factors could change RRD incidence in the population. Objective To determine whether the incidence of RRD in the Netherlands has changed over recent years and whether this change is associated with an altered prevalence of RRD risk factors. Design, Setting, and Participants This cohort study included data from all 14 vitreoretinal clinics in the Netherlands, as well as a large Dutch population-based cohort study. All patients who underwent surgical repair for a primary RRD in the Netherlands from January 1 to December 31, 2009, and January 1 to December 31, 2016, were analyzed, in addition to all participants in the population-based Rotterdam Study who were examined during these years. Analysis began February 2018 and ended November 2019. Exposures RRD risk factors, including age, male sex, cataract extraction, and myopia. Main Outcomes and Measures Age-specific RRD incidence rate in the Dutch population, as well as change in RRD incidence and risk factor prevalence between 2009 and 2016. Results In 2016, 4447 persons (median [range] age, 61 [3-96] years) underwent surgery for a primary RRD within the Netherlands, resulting in an RRD incidence rate of 26.2 per 100 000 person-years (95% CI, 25.4-27.0). The overall RRD incidence rate had increased by 44% compared with similar data from 2009. The increase was observed in both phakic (1994 in 2009 to 2778 in 2016 [increase, 39%]) and pseudophakic eyes (1004 in 2009 to 1666 in 2016 [increase, 66%]), suggesting that cataract extraction could not solely account for the overall rise. Over the same period, the prevalence of mild, moderate, and severe myopia among persons aged 55 to 75 years had increased by 15.6% (881 of 4561 [19.3%] vs 826 of 3698 [22.3%]), 20.3% (440 of 4561 [9.6%] vs 429 of 3698 [11.6%]), and 26.9% (104 of 4561 [2.3%] vs 107 of 3698 [2.9%]), respectively, within the population-based Rotterdam Study. Conclusions and Relevance In this study, an increase was observed in primary RRD incidence in the Netherlands over a 7-year period, which could not be explained by a different age distribution or cataract surgical rate. A simultaneous myopic shift in the Dutch population may be associated, warranting further population-based studies on RRD incidence and myopia prevalence. This cohort study assesses whether the incidence of rhegmatogenous retinal detachment has changed over recent years and whether this change is associated with an altered prevalence of rhegmatogenous retinal detachment risk factors in the Netherlands. Question What is the incidence of primary rhegmatogenous retinal detachment (RRD) in the Netherlands and has it changed over recent years? Findings In this cohort study, 4447 individuals in the Netherlands underwent surgery for RRD in 2016, resulting in an incidence of 26.2 per 100 000 inhabitants, an increase of 44% compared with similar data from 2009. Over the same period, an increase in myopia prevalence in a Dutch population-based cohort study was observed. Meaning In the Netherlands, an increase in RRD incidence may be associated with a simultaneous myopic shift in the population
Properties of generalized univariate hypergeometric functions
Based on Spiridonov's analysis of elliptic generalizations of the Gauss
hypergeometric function, we develop a common framework for 7-parameter families
of generalized elliptic, hyperbolic and trigonometric univariate hypergeometric
functions. In each case we derive the symmetries of the generalized
hypergeometric function under the Weyl group of type E_7 (elliptic, hyperbolic)
and of type E_6 (trigonometric) using the appropriate versions of the
Nassrallah-Rahman beta integral, and we derive contiguous relations using
fundamental addition formulas for theta and sine functions. The top level
degenerations of the hyperbolic and trigonometric hypergeometric functions are
identified with Ruijsenaars' relativistic hypergeometric function and the
Askey-Wilson function, respectively. We show that the degeneration process
yields various new and known identities for hyperbolic and trigonometric
special functions. We also describe an intimate connection between the
hyperbolic and trigonometric theory, which yields an expression of the
hyperbolic hypergeometric function as an explicit bilinear sum in trigonometric
hypergeometric functions.Comment: 46 page
A VERSATILE DETECTION SYSTEM FOR A BROAD RANGE MAGNETIC SPECTROGRAPH
The focal plane detector for the QMG/2 magnetic spectrograph of the Kernfysisch Versneller Instituut is described. It consists of two-dimensional position sensitive proportional detectors and scintillation detectors. The properties of the components of the set-up and of the system as a whole in conjunction with the associated electronics and software are presented. The system aUows easy optimization of spectrograph focusing and correction of kinematic effects. The position resolution is about 1 mm for relatively highly ionizing particles (50 MeV c~-particles), and slightly worse for low4onizing particles (50 MeV protons)
Analytic curves in algebraic varieties over number fields
We establish algebraicity criteria for formal germs of curves in algebraic
varieties over number fields and apply them to derive a rationality criterion
for formal germs of functions, which extends the classical rationality theorems
of Borel-Dwork and P\'olya-Bertrandias valid over the projective line to
arbitrary algebraic curves over a number field.
The formulation and the proof of these criteria involve some basic notions in
Arakelov geometry, combined with complex and rigid analytic geometry (notably,
potential theory over complex and -adic curves). We also discuss geometric
analogues, pertaining to the algebraic geometry of projective surfaces, of
these arithmetic criteria.Comment: 55 pages. To appear in "Algebra, Arithmetic, and Geometry: In Honor
of Y.i. Manin", Y. Tschinkel & Yu. Manin editors, Birkh\"auser, 200
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