Higher Order Two Step Mechanisms in Nucleon Antinucleon Annihilation and the OZI Rule

We evaluate three meson doorway mechanisms for nucleon-antinucleon annihilation at rest for the first time. Detailed results are presented for the final state phi pi0 originating from the 3S1 initial state and for the phi rho channel originating from 1S0. The results presented also include the improved contributions from two meson doorway states and from the tree diagrams. For all the channels considered a consistent explanation of large and small OZI violations emerges.Comment: 18 pages, 2 PostScript figures, will be published in Eur. Phys. J.

Erarbeitung eines Kommunikationskonzeptes für Premotion Andermatt

In Andermatt entsteht zurzeit das grösste Tourismusresort der Schweiz. Die Marketing- und Eventagentur Premotion, mit Hauptsitz in Luzern, sieht in dieser Destination sehr viel Potenzial und hat aus diesem Grund vor zwei Jahren einen zweiten Firmensitz in Andermatt eröffnet. In dieser Arbeit wird ein Kommunikationskonzept für Premotion Andermatt erar-beitet. Um die aktuelle Marktsituation in Andermatt aufzuzeigen, wurden qualitative Inter-views durchgeführt und in der Sekundärliteratur zu den Bedürfnissen und Trends der Event-branche recherchiert. Die oberste Priorität für Premotion Andermatt ist es, ihren Bekanntheitsgrad zu erhöhen. Dafür sollen besonders die Dialoggruppen Marketing-/Personal- und Eventverantwortliche in mittleren bis grossen Firmen, Geschäftsführer in kleinen bis mittleren Betrieben, sowie be-stehende Kunden angesprochen werden. Da sich das Tourismusresort Andermatt noch in der Entwicklung befindet, sieht die erarbeitete Strategie vor, dass in einer ersten Phase die Kun-den die Vision und die Entstehung des Tourismusresorts persönlich miterleben sollen. Sobald sich die Destination als eine der Top-Destinationen der Schweiz etabliert haben wird, wird das Verkaufsargument nicht mehr die Vision, sondern die Destination Andermatt an sich sein. Die Nachfrage nach Events wird bis dahin nochmals deutlich ansteigen und die Rolle als Eventdienstleister ist dann für Premotion Andermatt erfolgsversprechend. Um die festgesetzten Kommunikationsziele zu erreichen und somit die Kommunikation für Premotion Andermatt zu optimieren, sollen verschiedene Massnahmen umgesetzt wer-den. Unter den vorgeschlagenen Massnahmen nimmt die Online-Kommunikation einen ho-hen Stellenwert ein. Mittels Suchmaschinenoptimierung und Google AdWords sollen poten-zielle Kunden im Internet auf Premotion Andermatt aufmerksam gemacht werden. Eine wei-tere wichtige Massnahme ist die interne Kommunikation. Alle geplanten Massnahmen wer-den in einer Übersicht dargestellt, priorisiert und zeitlich strukturiert. Abschliessend werden Handlungsempfehlungen gegeben und erläutert, wie die Kommunikationsmassnahmen für Premotion Andermatt optimal in die Gesamtkommunikation eingebunden werden können

In-nozzle flow and spray characteristics of large two-stroke marine diesel fuel injectors

To further increase efficiency as well as to reduce emissions of large two-stroke marine Diesel engines, the understanding of the fuel injection processes and the resulting spray atomization characteristics is of high importance. The sheer dimensions, the uniflow scavenging design with the central exhaust valve position and the high swirl motion of the charge air is imposing the need for peripheral multiple fuel injector arrangement. The two or three fuel injectors are arranged by 180\ub0 resp. 120\ub0 and hence, a strongly asymmetrical and eccentrical atomizer design is given as all of the typically five orifices face a similar direction which is defined by the injector position and swirl flow. Experiments have shown that these characteristic nozzle tip bore arrangements lead to a strong spray deflection due to inhomogeneous velocity profiles induced by cavitation inside the orifice. Specifically designed transparent nozzles have been utilized to qualitatively investigate the in-nozzle cavitation flow phenomena. Furthermore, the influence on the subsequent atomization behaviour by simultaneously acquiring the spray morphology has been studied. A simplified transparent one-hole nozzle was used with a matching nozzle tip geometry representative for a large two-stroke marine Diesel engine injector. Fuel pressures of 50 MPa were applied to meet engine realistic injection conditions. Moreover, different degrees of hydro-erosive grinding were applied to the orifices to investigate the effects on the spray morphology with decreasing levels of in-nozzle flow cavitation derived by increasing inlet radii between main nozzle tip bore and orifice

Sedimentology-based reconstructions of paleoclimate changes in the Central Andes in response to the uplift of the Andes, Arica region between 19 and 21°S latitude, northern Chile

We focus on the sedimentological record of the Middle Miocene to modern deposits in the Andes of northern Chile between 19 and 21°S. These sediments, deposited at the Western Escarpment of the Central Depression, indicate successively more moisture on the western margin of the Altiplano and the Western Cordillera where the sources are. At the Pacific Coast, 20-Ma-old exposure ages and salic gypsisols reflect an existing and ongoing hyperarid climate. We interpret the increased divergence of climates between the Coast and the Altiplano as consequence of the Andean rise to elevations higher than approximately 2,500m a.s.l., when the topography of the Altiplano was sufficiently high and areally extensive to attract Atlantic moisture. Accordingly, the inferred general increase in run-off was closely coupled with the uplift of the Andes if the steady rise model applies. In case that the rapid rise model for Andean uplift is correct, the inferred changes in sediment transport would have occurred independently of uplift, requiring an alternative, yet unknown drive

Influence of nozzle geometry on spray and combustion characteristics related to large two-stroke engine fuel injection systems

As emission regulations for large two-stroke marine Diesel engines increase as well, the manufacturers face similar problems as small-sized engine builders. The fuel injection, spray formation and subsequent combustion process remain among the main drivers for emissions of direct-injection, compression-ignition internal combustion engines. Since the fuel injection nozzle design of large two-stroke marine Diesel engines differs significantly, not only in size but especially regarding their non-symmetricity and eccentrical orifice arrangement, compared with four-stroke engines, the bulk of research available related to this topic is very limited. To further deepen the understanding of how in-nozzle cavitation flow during the fuel injection process affects the combustion behaviour in large two-stroke marine Diesel engines, transparent nozzle geometries have been used to link the cavitation phenomena with spray and combustion characteristics. A total of six single-orifice nozzles based on the original five-orifice nozzle design of large two-stroke marine Diesel fuel injectors, with and without hydro-erosive grinding, have been experimentally investigated under realistic engine conditions using highspeed optical measurement techniques and a unique constant-volume spray chamber that geometrically represents a combustion chamber of a large two-stroke marine Diesel engine at top dead centre. The spray morphology and combustion results reveal significant differences between the non- and hydro-erosive ground nozzle geometries. While the standard and angled nozzle versions remain similar, the eccentrical nozzle with its distinctive in-nozzle swirl cavitation pattern behaves differently, leading to a very reliable start of ignition behaviour and extreme wide spray angle

Social Influencer. Eine Analyse ausgewählter visueller und auditiver Stile erfolgreicher Social Influencer auf YouTube

Visuelle Kommunikation gewinnt im Zusammenhang mit der Digitalisierung immer mehr an Bedeutung. So erfolgt die Kommunikation auf Social-Media-Plattformen wie Facebook, Instagram und YouTube fast nur noch mittels Bild- und Videosprache. Social Influencer nutzen diese Kommunikationsweise, um sich auf den genannten Kanälen eine große Community aufzubauen. Dabei entsteht ein Beziehungsverhältnis zwischen Social Influencer und Empfängern. Der vorliegende Beitrag untersucht, welche Faktoren dazu führen, dass Social Influencer „Communities“ von mehreren Tausend bis Millionen Menschen aufbauen können, von diesen als Vorbilder und Meinungsmacher angesehen werden und dass dabei ein Beziehungsverhältnis entsteht. Die Ergebnisse zeigen, dass Social Influencer mittels aktivierender Wirkung des Gesagten die „Interaktion“ fördern. Durch eine selbstoffenbarende und wertschätzende Wirkung wird ein Storytelling realisiert, die Authentizität und Glaubwürdigkeit erhöht und die Entstehung einer Beziehung gefördert. Die Gestik, erhöhte Sprechlautstärke und das schnelle Sprechtempo sorgen dabei beim Empfänger für eine kompetent und glaubwürdig wirkende Erscheinung des Social Influencers, während die Mimik „Freude“ Glücksgefühle beim Adressaten auslöst. Die Ergebnisse liefern somit qualitativ-explorative Erkenntnisse über Stile von Social Influencern und deren Umsetzung auf dem Social-Media-Kanal YouTube. Sie bieten Ansätze zur Erklärung des Beziehungsverhältnisses zwischen YouTuber und Community

Optical Investigation of Sooting Propensity of n-Dodecane Pilot/Lean-Premixed Methane Dual-Fuel Combustion in a Rapid Compression-Expansion Machine

International audienceThe sooting propensity of dual-fuel combustion with n-dodecane pilot injection in a lean-premixed methane-air charge has been investigated using an optically accessible Rapid Compression-Expansion Machine to achieve engine relevant pressure and temperature conditions at start of pilot injection. A Diesel injector with a 100 µm single-hole coaxial nozzle, mounted at the cylinder periphery, has been employed to admit the pilot fuel. The aim of this study was to enhance the fundamental understanding of soot formation and oxidation processes of n-dodecane in presence of methane in the air charge by parametric variation of methane equivalence ratio, charge temperature and pilot fuel injection duration. The influence of methane on ignition delay and flame extent of the pilot fuel jet has been determined by simultaneous OH* chemiluminescence and Schlieren imaging. The sooting behavior of the flame has been characterized using the 2D-DBI imaging methodology. The apparent soot black-body temperature has been measured 1D-resolved along the injector axis by applying an imaging spectrograph. Addition of methane into the air charge considerably prolongs the ignition delay with an increasing effect under less reactive conditions and with higher methane equivalence ratios. Therefore, the influence of methane on the formation of soot is twofold: in case of short pilot injection, the presence of methane was found to decrease the soot formation due to the leaner pilot fuel mixture at time of ignition. For longer pilot fuel injections, methane enhances the soot production by decreasing oxygen availability and introducing additional carbon. In all cases, methane strongly defers the oxidation of soot due to the lower availability of oxygen

Evaluating the Impact of an Interprofessional Practice Experience Involving Pharmacy and Dental Students on Medication Histories within an Urban Academic Dental Admissions Clinic

Primary Objective: To compare interprofessional (IP) care versus standard care on medication history clarifications in dental patients. Secondary Objectives: To assess the clinical significance of these clarifications with regards to the potential impact on dental treatment plans. To describe the interventions provided by IP care to clarify discrepancies and/or resolve medication-related problems