Modelling Accretion in Transitional Disks

Transitional disks are protoplanetary disk around young stars that display inner holes in the dust distribution within a few AU, which is accompanied nevertheless by some gas accretion onto the central star. These cavities could possibly be created by the presence of one or more massive planets. If the gap is created by planets and gas is still present in it, then there should be a flow of gas past the planet into the inner region. It is our goal to study the mass accretion rate into the gap and in particular the dependency on the planet's mass and the thermodynamic properties of the disk. We performed 2D hydro simulations for disks with embedded planets. We added radiative cooling from the disk surfaces, radiative diffusion in the disk midplane, and stellar irradiation to the energy equation to have more realistic models. The mass flow rate into the gap region depends, for given disk thermodynamics, non-monotonically on the mass of the planet. Generally, more massive planets open wider and deeper gaps which would tend to reduce the mass accretion into the inner cavity. However, for larger mass planets the outer disk becomes eccentric and the mass flow rate is enhanced over the low mass cases. As a result, for the isothermal disks the mass flow is always comparable to the expected mass flow of unperturbed disks M_d, while for more realistic radiative disks the mass flow is very small for low mass planets (<= 4 M_jup) and about 50% for larger planet masses. For the radiative disks that critical planet mass for the disk to become eccentric is much larger that in the isothermal case. Massive embedded planets can reduce the mass flow across the gap considerably, to values of about an order of magnitude smaller than the standard disk accretion rate, and can be responsible for opening large cavities. The remaining mass flow into the central cavity is in good agreement with the observations.Comment: 10 pages, 29 figures, accepted for publication in Astronomy & Astrophysic

Der heilige Send zu Nieder-Flörsheim

Das folgende bisher ungedruckte Sendweistum von Nieder-Flörsheim findet sich aufgezeichnet am Schluß einer Güterrenovation vom Jahre 1515 (Großh. Haus- und Staatsarchiv). Es ist undatiert, aber aus der Übereinstimmung der Schriftzüge mit denen der Renovation darf man wohl eine gleichzeitige Niederschrift annehmen. „Vßwysung des heylgen Sents ...

A note on couette flow of nematic crystals according to the Ericksen–Leslie theory

In order to model the flow of nematic crystals, the theoretical framework according to Ericksen and Leslie is applied. The essentials of the theory are compiled and then specialized to Couette flow. The profiles for linear velocity and orientation angle will be computed and, in particular, we shall also study the rise in temperature due to viscous dissipation, which is frequently ignored by mechanicians. Analytical and numerical solutions for the fields are derived for different boundary conditions and will subsequently be discussed.TU Berlin, Open-Access-Mittel - 201

Umweltbildung mit Wirkung : eine Arbeitshilfe

Umweltbildung hat über die Jahre viel Praxiserfahrung aufgebaut, die Qualität der Angebote ist hoch. Mit knapper werdenden Ressourcen rückt nun vermehrt die Wirkung der Umweltbildung ins Blickfeld. Mit einer Arbeitshilfe werden Anbietende dabei unterstützt, die Wirkung Ihrer Angebote benennen zu können, zu steigern und zu messen

Éducation à l‘environnement et efficacité : un outil de travail

Au fil des ans, l’éducation à l’environnement a acquis une grande expérience pratique et la qualité des offres est élevée. Avec la diminution des ressources, l’accent est désormais mis davantage sur l’efficacité. La brochure « Éducation à l‘environnement et efficacité » est conçue pour vous aider à identifier, améliorer et mesurer l’efficacité de vos offres de formation

A Meta-Analysis of Smart City Research and Its Future Research Implications

The aspired potentials of the "Smart City" (SC) and its deficits in practice are essential reasons why the subject is assigned to a rapidly growing body of literature. This situation requires a specific review of the literature summarizing the research efforts to date into research branches and topics, unifying essential basic concepts and thus forming a solid basis for futher research. The present study first derives a basic structure of research by an analysis of the available literature reviews. Subsequently, a systematic examination of SC literature by means of an EBSCO data query identifies the current research topics and compiles a comprehensive view of the research topics. The present study is therefore not only of interest for scientific use, but also offers practitioners an overview of the various sub-areas of a SC, as well as of the currently available findings and experiences in relation to the implementation of SC (sub-)projects

Improvement of lung preservation - From experiment to clinical practice

Background. Reperfusion injury represents a severe early complication following lung transplantation. Among the pathogenetic factors, the high potassium content of Euro-Collins(R) solution is discussed. Material and Methods: In a pig model of orthotopic left-sided lung transplantation we investigated the effect of Euro-Collins solution (EC: n=6) versus low potassium dextran (LPD: Perfadex(R): n = 6). Sham-operated (n = 6) animals served as control. Transplant function, cellular energy metabolism and endothelial morphology served as parameters. In a clinical investigation, 124 patients were evaluated following single (EC: n = 31; LPD n = 37) or double (EC: n = 17; LPD n = 39) lung transplantation, whose organs where preserved with EC (n = 48) or LPD (n = 76). Duration of ischemia, duration of ventilation and stay on ICU were registered. Primary transplant function was evaluated according to AaDO(2) values. Cause of early death (30 days) was declared. Results: Experimental results: After flush with EC and 18 h ischemia, a reduction of tissue ATP content (p < 0.01 vs inital value and LPD) was noted. Endothelial damage after ischemia was severe (p < 0.05 vs control), paO(2) was significantly decreased. Clinical results: In the LPD group, duration of ischemia was longer for the grafts transplanted first (SLTx and DLTx: p = 0.0009) as well as second (2. organ DLTx: p = 0.045). Primary transplant function was improved (day 0: SLTx: p = 0.0015; DLTx: p = 0.0095, both vs EC). Duration of ventilation and stay on ICU were shorter (n.s.). Reperfusion injury-associated death was reduced from 8% (EC) to 0 (LPD). Conclusion: In experimental lung preservation, LPD lead to an improved graft function. These results were confirmed in clinical lung transplantation. Clinical lung preservation, therefore, should be carried out by use of LPD. Copyright (C) 2002 S. Karger AG, Basel

Sammlung der Ordnungen und Statuten der Königlichen Haupt- und Residenzstadt Stuttgart

SAMMLUNG DER ORDNUNGEN UND STATUTEN DER KÖNIGLICHEN HAUPT- UND RESIDENZSTADT STUTTGART Sammlung der Ordnungen und Statuten der Königlichen Haupt- und Residenzstadt Stuttgart (-) Einband (-) Titelseite (-) Vorwort (-) Inhaltsverzeichnis (-) Bestimmungen über die An- und Abmeldung der in Stuttgart sich Aufhaltenden, sowie der Dienstboten ([1]) Börsen-Ordnung (3) Dienstmann-Ordnung (14) Droschken-Ordnung (22) Feldpolizei-Ordnung (42) Friedhof-Statut und Begräbnis-Ordnung (54) Gesinde-Ordnung (82) Holzmesser-Instruction (102) Inventirer-Instruction (105) Kaminfeger-Ordnung (115) Krankheitskosten-Versicherungsstatut (127) Latrinen-Ordnung (134) Mäkler-Ordnung (136) Markt-Ordnungen (139) Ortsbaustatut (161) Schlachthaus- und Fleischverkehrs-Ordnung (193) Straßenpolizei-Ordnung (208) Verbrauchssteuer-Ordnung (244) Wasserabgabe zu Privatzwecken (258) Wohnungsumzüge (264) Startseite (265) Druckfehler und Berechtigungen (280) Farbinformation (-) Einband (-