Thermally-driven Neutron Star Glitches

We examine the thermal and dynamical response of a neutron star to a sudden perturbation of the inner crust temperature. During the star's evolution, starquakes and other processes may deposit \gap 10^{42} ergs, causing significant internal heating and increased frictional coupling between the crust and the more rapidly rotating neutron superfluid the star is expected to contain. Through numerical simulation we study the propagation of the thermal wave created by the energy deposition, the induced motion of the interior superfluid, and the resulting spin evolution of the crust. We find that energy depositions of $\sim 10^{40}$ ergs produce gradual spin-ups above the timing noise level, while larger energy depositions produce sudden spin jumps resembling pulsar glitches. For a star with a temperature in the observed range of the Vela pulsar, an energy deposition of $\sim 10^{42}$ ergs produces a large spin-up taking place over minutes, similar to the Vela ``Christmas'' glitch. Comparable energy deposition in a younger and hotter ``Crab-like'' star produces a smaller spin-up taking place over $\sim 1$ day, similar to that seen during the partially time-resolved Crab glitch of 1989.Comment: 21 pages plus 17 figures, uuencode compressed Postscript. Accepted for publication in the Astrophysical Journa

Difficulties in the privatisation and reorganisation of the agricultural enterprises in Russia

Presently Russia is experiencing the complicated process of transforming the economic system of central planning into a socially oriented market economy. Of great importance for the success of this process is the institutional reshaping of the agricultural sector, particularly the privatisation of land and assets. In this paper the procedure and the problems of privatising Russian agriculture are extensively discussed against the background of the unfavourable development of the Russian agricultural sector. -- G E R M A N V E R S I O N: Gegenwärtig durchläuft Rußland einen komplizierten Prozeß der Transformation des zentral geplanten Wirtschaftssystems in eine soziale Marktwirtschaft. Von großer Bedeutung für den Erfolg dieses Prozesses ist der institutionelle Wandel des landwirtschaftlichen Sektors, insbesondere die Privatisierung von Land und sonstigem Vermögen. Vor dem Hintergrund der ungünstigen Entwicklung der russischen Landwirtschaft werden in dieser Arbeit die Vorgehensweise und die Probleme der russischen Landwirtschaft ausführlich diskutiert.

Recent developments in perturbation theory

Rayleigh-Schroeder perturbation theory - degenerate and non-degenerate states - quantum chemistry - other perturbation equation

First Records for \u3ci\u3eAeshna Sitchensis\u3c/i\u3e (Odonata: Aeshnidae) and \u3ci\u3eEnallagma Clausum\u3c/i\u3e (Odonata: Coenagrionidae), and a Northwestern Record for the State-Endangered \u3ci\u3eSomatochlora Incurvata\u3c/i\u3e (Odonata: Corduliidae) in Wisconsin

While surveying for Odonata in coastal peatlands and associated shoreline areas adjacent to Lake Superior in Wisconsin, we documented populations of two new state record species, the zig-zag darner (Aeshna sitchensis Hagen) and the alkali bluet (Enallagma clausum Morse). We also located a robust population of the state-endangered incurvate emerald (Somatochlora incurvata Walker) at the northwestern edge of the known range of this species. Adults and exuviae of A. sitchensis and S. incurvata were found at an insular fen on Stockton Island, Ashland County, within the Apostle Islands National Lakeshore (AINL). Breeding of both species had occurred in areas of the fen where small pools had dried by summer. Additionally, a single adult male A. sitchensis was collected in the City of Superior in Douglas County. Adult E. clausum were found at two sites: on the Lake Superior beach near the mouth of the Sand River within the AINL in Bayfield County, and along the northeast shore of Allouez Bay in the City of Superior in Douglas County

Passive Cooling of a Micromechanical Oscillator with a Resonant Electric Circuit

We cool the fundamental mode of a miniature cantilever by capacitively coupling it to a driven rf resonant circuit. Cooling results from the rf capacitive force, which is phase shifted relative to the cantilever motion. We demonstrate the technique by cooling a 7 kHz cantilever from room temperature to 45 K, obtaining reasonable agreement with a model for the cooling, damping, and frequency shift. Extending the method to higher frequencies in a cryogenic system could enable ground state cooling and may prove simpler than related optical experiments in a low temperature apparatus.Comment: 4 pages, 4 figures; minor changes to match published versio

Convex regions in the plane and their domes

We make a detailed study of the relation of a euclidean convex region $\Omega \subset \mathbb C$ to $\mathrm{Dome} (\Omega)$. The dome is the relative boundary, in the upper halfspace model of hyperbolic space, of the hyperbolic convex hull of the complement of $\Omega$. The first result is to prove that the nearest point retraction $r: \Omega \to \mathrm{Dome} (\Omega)$ is 2-quasiconformal. The second is to establish precise estimates of the distortion of $r$ near $\partial \Omega$