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Relativistic jets reside in high-energy astrophysical systems of all scales. Their interaction with the surrounding media is critical as it determines the jet evolution, observable signature, and feedback on the environment. During its motion the interaction of the jet with the ambient media inflates a highly pressurized cocoon, which under certain conditions collimates the jet and strongly affects its propagation. Recently, Bromberg et al. (2011b) derived a general simplified (semi)analytic solution for the evolution of the jet and the cocoon in case of an unmagnetized jet that propagates in a medium with a range of density profiles. In this work we use a large suite of 2D and 3D relativistic hydrodynamic simulations in order to test the validity and accuracy of this model. We discuss the similarities and differences between the analytic model and numerical simulations and also, to some extent, between 2D and 3D simulations. Our main finding is that although the analytic model is highly simplified, it properly predicts the evolution of the main ingredients of the jet-cocoon system, including its temporal evolution and the transition between various regimes (e.g., collimated to uncollimated). The analytic solution predicts a jet head velocity that is faster by a factor of about 3 compared to the simulations, as long as the head velocity is Newtonian. We use the results of the simulations to calibrate the analytic model which significantly increases its accuracy. We provide an applet that calculates semi-analytically the propagation of a jet in an arbitrary density profile defined by the user at

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Die megalithischen Grabanlagen von Sion-'LePetit Chasseur I+III' bieten eine einmalige Chance, Strukturen von sozialem Wandel über fast das gesamte 3. Jahrtausend v. Chr. hinweg kontinuierlich zu verfolgen und aufzuzeigen, wie eine lokale Bevölkerung die europaweiten ideologischen Veränderungen dieser Zeit rezipiert. Unsere Analyse der Funeralbauten, der anthropomorphen Stelen und der materiellen Hinterlassenschaften (die als drei unterschiedliche Quellengruppen anzusehen sind) führen uns das Ringen zwischen Tradition und Innovation vor Augen sowie die sukzessiven Adaptionen einer lokalen spätneolithischen Bevölkerung an die verschiedenen Zweige der Glockenbecher-Ideologie und dann der Frühbronzezeit. In der Folge vergleichen wir Sion mit der ähnlich strukturierten Fundstelle von Aosta-'St.Martin-de-Corléans' und stellen beide Komplexe in den weiteren europäischen Rahmen des 3. Jahrtausends v. Chr. Dieser Vergleich beginnt mit der Einwanderung von Jamnaja-Bevölkerungen der nordpontischen Steppen nach Ost-und Südosteuropa und endet mit der Entstehung des Glockenbecher-Phänomens im Westen der Iberischen Halbinsel. Dies alles ist Inhalt eines weiten Transformationshorizonts der Zeit zwischen 2900 und 2700 v. Chr. Spezifische Innovationen darin werden beschrieben und analysiert. Les monuments funéraires mégalithiques de Sion-«Petit-Chasseur I+III» offrent une chance unique de suivre en continu des mutations sociales durant presque tout le 3 e millénaire av. J.-C. et de démontrer comme une population locale assimile les changements idéologiques contemporains survenus dans toute l'Europe. L'analyse des constructions funéraires, des stèles anthropomorphes et des vestiges matériels (à considérer comme trois groupes de sources distincts) révèle la lutte entre tradition et innovation ainsi que les adaptations successives de la population du Néolithique tardif aux différents courants de l'idéologie campaniforme, puis de celle du Bronze ancien. Par la suite, Sion est comparé au site d'Aoste-«St. Martin-de-Corléans», de structure similaire, et les deux ensembles sont replacés dans le cadre européen du 3 e millénaire av. J.-C. Cette comparaison débute avec l'immigration en Europe orientale et méridionale de populations jamnaja des steppes situées au nord de la mer Noire et s'achève avec l'émergence du phénomène campaniforme dans l'ouest de la péninsule ibérique. Tout ceci fait partie d'un vaste horizon de transformation situé entre 2900 et 2700 av. J.-C. Des innovations spécifiques de cette période sont décrites et analysées. The megalithic cemetery of Sion-'Le Petit Chasseur I+III' offers a unique chance to analyse patterns of social change throughout most of the third millennium BC, and to demonstrate how a local population adjusts to the pan-European ideological changes of that period. Our analysis of the funeral monuments, the anthropomorphic stelae, and the material remains (which form three independent Quellengruppen) shows the tensions between tradition and innovation, and the successive adaptions of a local Late Neolit...

Visual hallucinations (VH) are a core feature of dementia with Lewy bodies (DLB), but little is known about their phenomenology. A total of 73 dementia patients (42 DLB, 30 Alzheimer's disease [AD], 1 undiagnosed) in contact with clinical services were assessed with a detailed standardized inventory. DLB was diagnosed according to the criteria of McKeith and colleagues, AD was diagnosed using the NINCDSADRDA criteria. Autopsy confirmation has been obtained when possible. VH were defined using the definition of Bums and colleagues. Detailed descriptions of hallucinatory experiences were recorded. Annual follow-up interviews were undertaken. The clinical diagnosis has been confirmed in 18 of the 19 cases that have come to autopsy. A total of 93% of DLB patients and 27% of AD patients experienced VH. DLB patients were significantly more likely to experience multiple VH that persisted over follow-up. They were significantly more likely to hear their VH speak but there were no significant differences in the other phenomenological characteristics including whether the hallucinations moved, the time of day that they were experienced, their size, the degree of insight, and whether they were complete. VH may be more likely to be multiple, to speak, and to be persistent in DLB patients. These characteristics could potentially aid accurate diagnosis.