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Background Implantable cardioverter-defibrillator (ICD) therapy is well established for secondary prevention, but studies on the efficacy and safety in elderly patients are still lacking. This retrospective study compared the outcome after ICD implantation between octogenarians and other age groups. Methods Data were obtained from a local ICD registry. Patients who received ICD implantation for secondary prevention at our department were included. All-cause mortality, appropriate ICD therapy and acute adverse events requiring surgical intervention were compared between different age groups. Results 519 patients were enrolled, 34 of whom were aged ≥ 80 years. During the median follow-up of 35 months after ICD implantation 129 patients (annual mortality rate 5.0%) had died, including 16 patients aged ≥ 80 years (annual mortality rate 9.4%). The mortality rate of patients aged ≥ 80 years was significantly higher than that of patients aged ≤ 69 years (p p n = 13) and not age-related. Conclusion Age is an independent predictor of mortality after ICD implantation for secondary prevention. Mortality rates did not differ significantly between octogenarians and other elderly aged 70–79 years. Appropriate ICD therapy and acute adverse events leading to surgical intervention were not age-related. Implantable cardioverter-defibrillator therapy for secondary prevention seems to be an effective and safe treatment modality in octogenarians.

Collective rotations and tilts of oxygen polyhedra play a crucial role in the physical properties of complex oxides such as magnetism and conductivity. Such rotations can be tuned by preparing thin films in which dimensionality, strain, and interface effects come into play. However, little is known of the tilt and rotational distortions in films a few unit cells thick including the question of if coherent tilt patterns survive at all in this ultrathin limit. Here, a series of films of perovskite LaNiO3 is studied and it is shown that the phonon mode related to oxygen octahedral tilts can be followed by Raman spectroscopy down to a film thickness of three pseudocubic perovskite unit cells (∼1.2 nm). To push the limits of resolution to the ultrathin regime, a statistical analysis method is introduced to separate the Raman signals of the film and substrate. Most interestingly, these analyses reveal a pronounced hardening of the tilt vibrational mode in the thinnest films. A comparison between the experimental results, first principles simulations of the atomic structure, and the standing wave model, which accounts for size effects on the phononic properties, reveals that in the ultrathin regime, the Raman spectra are a hybrid entity of both the bulk and surface phononic behavior. These results showcase Raman spectroscopy as a powerful tool to probe the behavior of perovskite films down to the ultrathin limit., APL Materials, 8 (6), ISSN:2166-532X

A strong coupling of the lattice to functional properties is observed in many transition metal oxide systems, such as the ABO(3) perovskites. In the quest for tailor-made materials, it is essential to be able to control the structural properties of the compound(s) of interest. Here, thin film solid solutions that combine NdNiO3 and LaNiO3, two materials with the perovskite structure but distinct space groups, are analyzed. Raman spectroscopy and scanning transmission electron microscopy are combined in a synergistic approach to fully determine the mechanism of the structural crossover with chemical composition. It is found that the symmetry transition is achieved by phase coexistence in a way that depends on the substrate selected. These results carry implications for analog-tuning of physical properties in future functional materials based on these compounds.

The research project was funded by the International Union of Railways (UIC)., Background: Shifting travellers from air to rail can reduce environmental impacts and is an important European Union goal. Online travel planning applications allow travellers to easily compare air and rail transport choices, however, they may not accurately consider time travellers spend at the airport or railway station since these depend on buffer times travellers use to protect against delays. Methods: This research investigated the actual time spent at airports and railway stations to analyse the accuracy of travel planning applications and help improve the quality of travel time estimates. The research used a travel time recording application to determine the time spent by passengers at airports and railway stations. Data was collected for 312 trips. The research was supplemented by an extensive literature review of dwell times and multimodal travel planning applications. Results: The research found that travellers spent an average of 157 minutes at airports and 32 minutes at railway stations. Comparing these results to travel planning application, the information shows that the applications significantly underestimate time spent at airports and slightly underestimate time spent at railway stations. The use of unrealistic airport waiting times in travel planning applications distorts traveller perception in favour of air travel. Conclusion: Therefore, railway operators should support the development of improved travel planning applications that better consider waiting times. Improving these applications would be much more cost effective than infrastructure improvements designed to save a few minutes of travel time.

The simulation of the structural crashworthiness of automotive shells is a key function during the product design and development phase. Modern road vehicles require high-complexity product design in order to satisfy the demanding market and the increasing requirements of crash test safety regulations. Product safety issues are highly related to the development of manufacturing processes and material treatment, which will allow for the necessary product structural properties and crash safety. The consideration of the structural properties after the forming process of sheet metal parts and their welding into body assemblies emerge to be essential for a more accurate modelling of the crash behaviour. In this paper, a practical approach for realising the simulation chaining of forming, welding and crash for structural shell assemblies is proposed. The attained structural results of single-sheet metal components are transferred into an integrated model, which enables the side impact simulation of a B-pillar a...

A marked conductivity enhancement is reported in 6-11 unit cell LaNiO

The interactions of a beam of hard and spatio-temporally coherent X-rays with a soft-matter sample primarily induce a transverse distribution of exit phase variations δϕ (retardations or advancements in pieces of the wave front exiting the object compared to the incoming wave front) whose free-space propagation over a distance z gives rise to intensity contrast gz. For single-distance image detection and |δϕ| ≪ 1 all-order-in-z phase-intensity contrast transfer is linear in δϕ. Here we show that ideal coherence implies a decay of the (shot-)noise-to-signal ratio in gz and of the associated phase noise as z(-1/2) and z(-1), respectively. Limits on X-ray dose thus favor large values of z. We discuss how a phase-scaling symmetry, exact in the limit δϕ → 0 and dynamically unbroken up to |δϕ| ∼ 1, suggests a filtering of gz in Fourier space, preserving non-iterative quasi-linear phase retrieval for phase variations up to order unity if induced by multi-scale objects inducing phase variations δϕ of a broad spatial frequency spectrum. Such an approach continues to be applicable under an assumed phase-attenuation duality. Using synchrotron radiation, ex and in vivo microtomography on frog embryos exemplifies improved resolution compared to a conventional single-distance phase-retrieval algorithm.

The simulation of the crash behaviour of whole automotive body structures has gained increasing value in the development phase of the overall product cycle in the recent years. In the automotive body-in-white cost and time as well as high accuracy and quality of structural components are main issues. Particularly, when it comes to safety matters, the crash behaviour of the overall vehicle shell is a major concern. So as to describe the manufacturing process chain more precisely and to predict the structural behaviour at early stages of product and process planning, an interlinking of forming, trimming and welding models within a structural manufacturing computation chain is necessary. The computed structural properties after manufacturing and joining of body assemblies appear to be essential for a more accurate description of the actual crash behaviour. Considering the structural properties after the forming and trimming process for simulating welding tasks and finally the crash behaviour requires a multifaceted modelling method. In this paper, a practicable strategy for realising the simulation chain forming–welding–crash of whole structural assemblies by means of shell element models is introduced. The complete computed results of a forming process simulation, such as residual stresses, plastic strains, and material thinning are transferred into the simulation of welding heat effects. Further on, the structural properties after forming combined with the thermal distribution due to the welding process and the mechanical clamping conditions within a thermomechanical computation allow a conclusion on the final shape, residual stresses and plastic strains in the weld seam area of the manufactured structure. Finally, the attained structural results are converted into the required data format by means of a developed conversion routine, which enables the side crash simulation of a sill board assembly automotive structure on a rigid pole considering the entire preliminary manufacturing process chain.

In recent years the simulation of manufacturing chains and of the crash behaviour of automotive sheet metal structures has gained more ground on its way to be established in accompanying the overall product cycle. In the automotive press and welding plants high accuracy and quality of sheet metal structures is essential in order to achieve the intended passive crashworthiness of the overall vehicle body. So as to describe the manufacturing process chain more precisely and to predict the structural behaviour at early stages of product and production planning, an interlinking of forming, welding and crash models within a structural computation chain is necessary. Considering the structural properties of sheet metal parts after the forming process for simulating welding tasks and finally the crash behaviour requires a multifaceted modelling method. In this paper a practicable strategy of realising the simulation chain forming-welding-crash of sheet metal structures is introduced by means of shell element models. The complete computed results of a forming process simulation, such as residual stresses, plastic strains and material thinning are transferred onto a prepared shell mesh based on the CAD geometry of the component, which satisfies the requirements of a welding computation. Further on, the structural properties after forming, the thermal distribution due to the welding process and the mechanical clamping conditions are combined in a thermo-mechanical computation of the welding effects to calculate the final shape, residual stresses and material thinning of the manufactured sheet metal structure. Finally, the attained structural results are converted into the required data-format by means of a developed conversion routine, which enables the setup of a crash model considering the entire preliminary manufacturing chain. In this contribution the structural behaviour along the introduced simulation chain is analysed step by step and the rendered results are discussed and compared with performed measurements.

Homogenous turbostratic graphite nanofibres (TGNFs) have been synthesized by heat treatment of electrospun polyacrylonitrile in dimethylsulphoxide, offering a solution route of low toxicity to manufacture sub-60 nm diameter TGNFs. Characterization techniques including X-ray diffraction, scanning- and transmission electron microscopy have been used to study the graphitization process, and structural morphology of the nanofibres. The TGNFs have an entangled micro-fibril structure with turbostratic ordering of up to 40 graphene layers after heat treatment at 3000 °C.

Despite numerous advantages, welding simulations are seldom used to solve manufacturing problems in the automotive industry. For that reason, the Institute for Machine Tools and Industrial Management (iwb) of the Technical University of Munich is researching different simulation methods in order to overcome existing obstacles that prevent their use and to develop industrial applications.

In der Automobilindustrie werden bisher Schweissimulationen trotz der Vielzahl an Vorteilen lediglich vereinzelt zur Losung von fertigungstechnischen Problemen verwendet. Am Institut fur Werkzeugmaschinen und Betriebswissenschaften (iwb) der TU Munchen werden unterschiedliche Simulationsmethoden untersucht, um bestehende Einsatzhemmnisse aufzulosen und industrielle Einsatzmoglichkeiten zu erarbeiten.

In the field of light weight frame structures the assurance of dimensional accuracy and the prediction of structural properties especially during and after welding processes are of great importance. The problem in this regard mostly arises from the used welding technique which is characterised by complex interactions of various parameters. A simulative approach is useful in order to predict the structural behaviour and to improve the geometrical quality of joined light weight components after welding. As such, it contributes to reduce process adjustments in the early stage of the product life cycle, and therefore helps to save time and costs. In this paper an approach for modelling the innovative joining process of composite extruded profiles by friction stir welding is presented.

A marked conductivity enhancement is reported in 6-11 unit cell LaNiO3 thin films. A maximal conductivity is also observed in ab initio calculations for films of the same thickness. In agreement with results from state of the art scanning transmission electron microscopy, the calculations also reveal a differentiated film structure comprising characteristic surface, interior, and heterointerface structures. Based on this observation, a three-element parallel conductor model is considered and leads to the conclusion that the conductivity enhancement for films of 6-11 unit cells, stems from the onset of intercompetition between the three local structures in the film depth. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper considers the realized returns of individual investors in warrants and leverage certificates. First, we derive a general formula that analytically decomposes the return into several economically meaningful components that are related to investor’s trading behavior and the issuers’ price-setting strategy. Second, we use a large trade dataset to analyze returns along these components and also link them to investors’ risk taking strategy. Our main findings are threefold: (i) The overall performance is poor. (ii) Investors show neutral timing skills, while the main performance driver is the issuers’ price-setting. (iii) Higher risk taking by investors diminishes the performance further. Our results imply that retail investors do not achieve a pecuniary benefit from the considered financial innovations.

This paper analyzes the pricing policy of banks for retail exchange-traded leverage certificates. Based on a unique trade data set, we analyze the order flow induced by the investors and compare traded prices with corresponding theoretical fair product values. Our major results are: (i) Intraday effect: Traded leverage certificates are overpriced but the overpricing strongly depends on the time of day the trade is made. At the end of the underlying’s daily trading hours, issuers increase the prices. (ii) Interday effect: The overpricing decreases over the certificate’s lifetime. (iii) The intraday (interday) effect is more pronounced the more (less) likely a premature knock-out of the certificate is. (iv) Both effects are consistent with the investors’ order flow and the gap risk faced by issuers. Banks try to exploit systematic trading patterns of investors to increase their profits.