Future geodesic completeness of some spatially homogeneous solutions of the vacuum Einstein equations in higher dimensions

It is known that all spatially homogeneous solutions of the vacuum Einstein equations in four dimensions which exist for an infinite proper time towards the future are future geodesically complete. This paper investigates whether the analogous statement holds in higher dimensions. A positive answer to this question is obtained for a large class of models which can be studied with the help of Kaluza-Klein reduction to solutions of the Einstein-scalar field equations in four dimensions. The proof of this result makes use of a criterion for geodesic completeness which is applicable to more general spatially homogeneous models.Comment: 18 page

Future non-linear stability for reflection symmetric solutions of the Einstein-Vlasov system of Bianchi types II and VI0_0

Using the methods developed for the Bianchi I case we have shown that a boostrap argument is also suitable to treat the future non-linear stability for reflection symmetric solutions of the Einstein-Vlasov system of Bianchi types II and VI$_0$. These solutions are asymptotic to the Collins-Stewart solution with dust and the Ellis-MacCallum solution respectively. We have thus generalized the results obtained by Rendall and Uggla in the case of locally rotationally symmetric Bianchi II spacetimes to the reflection symmetric case. However we needed to assume small data. For Bianchi VI$_0$ there is no analogous previous result.Comment: 30 page

Kinderchirurgische Operationen unter Einsatz von 5mm laparoskopischen Klammernahtgeräten

Roll 715a. SLU vs. Wash. U. (Washington University)(tennis); Pius Library. Image 16 of 35. (18 April 1961) [PHO 1.715a.16]The Boleslaus Lukaszewski (Father Luke) Photographs contain more than 28,000 images of Saint Louis University people, activities, and events between 1951 and 1970. The photographs were taken by Boleslaus Lukaszewski (Father Luke), a Jesuit priest and member of the University's Philosophy Department faculty

Arginine-rhamnosylation as new strategy to activate translation elongation factor P

Ribosome stalling at polyproline stretches is common and fundamental. In bacteria, translation elongation factor P (EF-P) rescues such stalled ribosomes, but only when it is post-translationally activated. In Escherichia coli, activation of EF-P is achieved by (R)-beta-lysinylation and hydroxylation of a conserved lysine. Here we have unveiled a markedly different modification strategy in which a conserved arginine of EF-P is rhamnosylated by a glycosyltransferase (EarP) using dTDP-L-rhamnose as a substrate. This is to our knowledge the first report of N-linked protein glycosylation on arginine in bacteria and the first example in which a glycosylated side chain of a translation elongation factor is essential for function. Arginine-rhamnosylation of EF-P also occurs in clinically relevant bacteria such as Pseudomonas aeruginosa. We demonstrate that the modification is needed to develop pathogenicity, making EarP and dTDP-L-rhamnose-biosynthesizing enzymes ideal targets for antibiotic development

IN-SITU AND HIERARCHICAL INVESTIGATION OF ALLOYS AND COMPONENTS FOR ADDITIVE MANUFACTURING

In this work, different materials tailored for AM produced by different AM processes are characterized on AM relevant scales. Among the AM techniques, Laser Powder Bed Fusion (LPBF) stands out as it is used to produce near-net-shape metallic components with complex geometries and higher material efficiency, typically replacing multiple conventional components with savings in material, tooling and assembly costs. However, this technique is only applicable to single materials and has size limitations. Therefore, as a second route, we are also investigating the production of multi-material AM components with integrated multifunctionality and without size limitations by combining directed energy deposition (DED) and metal spraying technologies, using specially developed materials with incorporated nanotechnologies to enhance material properties. Since the mechanical properties and performance of final AM parts are inherited for the entire processing history and the material used, the relevant scales range from several centimeters down to the submicron range. Therefore, the aim of our study is to develop a correlative imaging approach that allows the linking of the relevant scales mentioned above in order to address the scientific challenges of AM. The beamlines ID16B and BM18 at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, make this approach possible