Kathetergestützte Aortenklappenimplantation: Was müssen Anästhesisten wissen?

Zusammenfassung: Der chirurgische Aortenklappenersatz gilt als Goldstandard in der Therapie der hochgradigen Aortenklappenstenose. Die veränderte Demografie konfrontiert die behandelnden medizinischen Fachdisziplinen jedoch mit einem zunehmend höheren Risikoprofil der Patienten; dies machte die Entwicklung neuer weniger invasiver Behandlungsalternativen in der operativen Therapie der Aortenklappenstenose erforderlich. Dieser Entwicklungsprozess führte über die Minithorakotomie hin zur kathetergestützten Aortenklappenimplantation ("transcatheter aortic valve implantation", TAVI). Die TAVI ist ein neues therapeutisches Verfahren zur Behandlung von Patienten mit hochgradiger Aortenklappenstenose und hohem perioperativen Morbiditäts- sowie Mortalitätsrisiko für einen konventionellen Aortenklappenersatz. Da die TAVI am schlagenden Herzen ohne Sternotomie und Herz-Lungen-Maschine durchgeführt werden kann, eignet sich dieses Verfahren insbesondere für den älteren, multimorbiden und/oder kardial voroperierten Patienten. Die ersten Ergebnisse großer prospektiver Multizenterstudien unterstreichen den Stellenwert der TAVI in der modernen Behandlung von Hochrisikopatienten mit symptomatischer Aortenklappenstenose. Die TAVI erfordert vom Anästhesisten neben dem Verständnis des chirurgischen Ablaufs die genaue Kenntnis des perioperativen anästhesiologischen Managements und der möglichen Komplikationen des Verfahren

Beam interactions in one-dimensional saturable waveguide arrays

The interaction between two parallel beams in one-dimensional discrete saturable systems has been investigated using lithium niobate nonlinear waveguide arrays. When the beams are separated by one channel and in-phase it is possible to observe soliton fusion at low power levels. This new result is confirmed numerically. By increasing the power, soliton-like propagation of weakly-coupled beams occurs. When the beams are out-of-phase the most interesting result is the existence of oscillations which resemble the recently discovered Tamm oscillations.Comment: 5 pages, 6 figures, submitted to Phys. Rev.

ClimWood2030, Climate benefits of material substitution by forest biomass and harvested wood products: Perspective 2030 - Final Report

The ClimWood2030 study, commissioned by DG CLIMA of the European Commission, quantifies the five ways in which the EU forest sector contributes to climate change mitigation: carbon sequestration and storage in EU forests, carbon storage in harvested wood products in the EU, substitution of wood products for functionally equivalent materials and substitution of wood for other sources of energy, and displacement of emissions from forests outside the EU. It also explores through scenario analysis, based on a series of interlocking models (GLOBIOM, G4M and WoodCarbonMonitor), along with detailed analysis of Forest Based Functional Units, based on life cycle assessment (LCA), the consequences for GHG balances of policy choices at present under consideration. The focus is on the EU-28, but GHG balances for other parts of the world are also considered, notably to assess consequences of EU policy choices for other regions. The five scenarios are (I) The ClimWood2030 reference scenario, (II) Increase carbon stock in existing EU forests, (III) Cascade use – increase recovery of solid wood products, (IV) Cascade use – prevent first use of biomass for energy and (V) Strongly increase material wood use. The study presents detailed scenario results for key parameters, the policy instruments linked to the scenarios, and main conclusions

Integrated Detector Control and Calibration Processing at the European XFEL

The European X-ray Free Electron Laser is a high-intensity X-ray light source currently being constructed in the area of Hamburg, that will provide spatially coherent X-rays in the energy range between $0.25\,\mathrm{keV}$ and $25\,\mathrm{keV}$. The machine will deliver $10\,\mathrm{trains/s}$, consisting of up to $2700\,\mathrm{pulses}$, with a $4.5\,\mathrm{MHz}$ repetition rate. The LPD, DSSC and AGIPD detectors are being developed to provide high dynamic-range Mpixel imaging capabilities at the mentioned repetition rates. A consequence of these detector characteristics is that they generate raw data volumes of up to $15\,\mathrm{Gbyte/s}$. In addition the detector's on-sensor memory-cell and multi-/non-linear gain architectures pose unique challenges in data correction and calibration, requiring online access to operating conditions and control settings. We present how these challenges are addressed within XFEL's control and analysis framework Karabo, which integrates access to hardware conditions, acquisition settings (also using macros) and distributed computing. Implementation of control and calibration software is mainly in Python, using self-optimizing (py) CUDA code, numpy and iPython parallels to achieve near-real time performance for calibration application.Comment: Proceeding ICALEPS 201

Generalized Fano lineshapes reveal exceptional points in photonic molecules

The optical behavior of coupled systems, in which the breaking of parity and time-reversal symmetry occurs, is drawing increasing attention to address the physics of the exceptional point singularity, i.e., when the real and imaginary parts of the normal-mode eigenfrequencies coincide. At this stage, fascinating phenomena are predicted, including electromagnetic-induced transparency and phase transitions. To experimentally observe the exceptional points, the near-field coupling to waveguide proposed so far was proved to work only in peculiar cases. Here, we extend the interference detection scheme, which lies at the heart of the Fano lineshape, by introducing generalized Fano lineshapes as a signature of the exceptional point occurrence in resonant-scattering experiments. We investigate photonic molecules and necklace states in disordered media by means of a near-field hyperspectral mapping. Generalized Fano profiles in material science could extend the characterization of composite nanoresonators, semiconductor nanostructures, and plasmonic and metamaterial devices

Solitary waves in the Nonlinear Dirac Equation

In the present work, we consider the existence, stability, and dynamics of solitary waves in the nonlinear Dirac equation. We start by introducing the Soler model of self-interacting spinors, and discuss its localized waveforms in one, two, and three spatial dimensions and the equations they satisfy. We present the associated explicit solutions in one dimension and numerically obtain their analogues in higher dimensions. The stability is subsequently discussed from a theoretical perspective and then complemented with numerical computations. Finally, the dynamics of the solutions is explored and compared to its non-relativistic analogue, which is the nonlinear Schr{\"o}dinger equation. A few special topics are also explored, including the discrete variant of the nonlinear Dirac equation and its solitary wave properties, as well as the PT-symmetric variant of the model

A Search for Selectrons and Squarks at HERA

Data from electron-proton collisions at a center-of-mass energy of 300 GeV are used for a search for selectrons and squarks within the framework of the minimal supersymmetric model. The decays of selectrons and squarks into the lightest supersymmetric particle lead to final states with an electron and hadrons accompanied by large missing energy and transverse momentum. No signal is found and new bounds on the existence of these particles are derived. At 95% confidence level the excluded region extends to 65 GeV for selectron and squark masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure

Low Q^2 Jet Production at HERA and Virtual Photon Structure

The transition between photoproduction and deep-inelastic scattering is investigated in jet production at the HERA ep collider, using data collected by the H1 experiment. Measurements of the differential inclusive jet cross-sections dsigep/dEt* and dsigmep/deta*, where Et* and eta* are the transverse energy and the pseudorapidity of the jets in the virtual photon-proton centre of mass frame, are presented for 0 < Q2 < 49 GeV2 and 0.3 < y < 0.6. The interpretation of the results in terms of the structure of the virtual photon is discussed. The data are best described by QCD calculations which include a partonic structure of the virtual photon that evolves with Q2.Comment: 20 pages, 5 Figure

Simulating magnetized neutron stars with discontinuous Galerkin methods

Discontinuous Galerkin methods are popular because they can achieve high order where the solution is smooth, because they can capture shocks while needing only nearest-neighbor communication, and because they are relatively easy to formulate on complex meshes. We perform a detailed comparison of various limiting strategies presented in the literature applied to the equations of general relativistic magnetohydrodynamics. We compare the standard minmod/$\Lambda\Pi^N$ limiter, the hierarchical limiter of Krivodonova, the simple WENO limiter, the HWENO limiter, and a discontinuous Galerkin-finite-difference hybrid method. The ultimate goal is to understand what limiting strategies are able to robustly simulate magnetized TOV stars without any fine-tuning of parameters. Among the limiters explored here, the only limiting strategy we can endorse is a discontinuous Galerkin-finite-difference hybrid method

Paradoxical Evidence Integration in Rapid Decision Processes

Decisions about noisy stimuli require evidence integration over time. Traditionally, evidence integration and decision making are described as a one-stage process: a decision is made when evidence for the presence of a stimulus crosses a threshold. Here, we show that one-stage models cannot explain psychophysical experiments on feature fusion, where two visual stimuli are presented in rapid succession. Paradoxically, the second stimulus biases decisions more strongly than the first one, contrary to predictions of one-stage models and intuition. We present a two-stage model where sensory information is integrated and buffered before it is fed into a drift diffusion process. The model is tested in a series of psychophysical experiments and explains both accuracy and reaction time distributions