Methodological Gaps in Left Atrial Function Assessment by 2D Speckle Tracking Echocardiography

Abstract The assessment of left atrial (LA) function is used in various cardiovascular diseases. LA plays a complementary role in cardiac performance by modulating left ventricular (LV) function. Transthoracic two-dimensional (2D) phasic volumes and Doppler echocardiography can measure LA function non‑invasively. However, evaluation of LA deformation derived from 2D speckle tracking echocardiography (STE) is a new feasible and promising approach for assessment of LA mechanics. These parameters are able to detect subclinical LA dysfunction in different pathological condition. Normal ranges for LA deformation and cut-off values to diagnose LA dysfunction with different diseases have been reported, but data are still conflicting, probably because of some methodological and technical issues. This review highlights the importance of an unique standardized technique to assess the LA phasic functions by STE, and discusses recent studies on the most important clinical applications of this technique.

integrated method for improving risk analysis using human factors methods and virtual reality

Magdeburg, Univ., Fak. für Informatik, Diss., 2009

Wireless communication techniques for indoor positioning and tracking applications

Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2010

Optimization-based solutions to constrained trajectory-tracking and path-following problems

Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2012

Advanced production systems : developing context-oriented method and adaptation capabilities for enhanced supply network

Magdeburg, Univ., Fak. für Maschinenbau, Diss., 2014

Line-fitting method of model order reduction for elastic multibody systems

Magdeburg, Univ., Fak. für Maschinenbau, Diss., 2015

Development of a new method for the characterisation of bioreactors concerning heat and mass transfer

Since the specific heat transfer coefficient (UA) and the volumetric mass transfer coefficient (kLa) play an important role for the design of biotechnological processes, different techniques were developed in the past for the determination of these parameters. However, these approaches often use imprecise dynamic methods for the description of stationary processes and are limited towards scale and geometry of the bioreactor. Therefore, the aim of this thesis was to develop a new method, which overcomes these restrictions. This new approach is based on a permanent production of heat and oxygen by the constant decomposition of hydrogen peroxide in continuous mode. Since the degradation of H2O2 at standard conditions only takes place by the support of a catalyst, different candidates were investigated for their potential (regarding safety issues and reaction kinetic). Manganese-(IV)-oxide was found to be suitable. To compensate the inactivation of MnO2, a continuous process with repeated feeds of fresh MnO2 was established. Subsequently, a scale-up was successfully carried out from 100 mL to a 5 litre glass bioreactor (UniVessel®)To show the applicability of this new method for the characterisation of bioreactors, it was compared with common approaches. With the newly established technique as well as with a conventional procedure, which is based on an electrical heat source, specific heat transfer coefficients were measured in the range of 17.1 – 24.8 W/K for power inputs of about 50 – 70 W/L. However, a first proof of concept regarding the mass transfer showed no constant kLa for different dilution rates up to 0.04 h-1.Based on this, consecutive studies concerning the mass transfer should be made with higher volume flows, due to more even inflow rates. In addition, further experiments are advisable, to analyse the heat transfer in single-use bioreactors and in larger common systems.

The differentiation of character state relationships by binary coding and the monothetic subset method / Hymen Marx, George B. Rabb and Harold K. Voris.

v.72:no.1(1977)

On the upper bound of the number of limit cycles obtained by the second order averaging method I

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On the upper bound of the number of limit cycles obtained by the second order averaging method II

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L' Ensenyament per tasques: programació d'una assignatura de traducció de l'alemany a l'espanyol

In this work we present a proposal for a course in translation from German into Spanish following the task based approach as known in second language acquisition. The aim is to improve the translation competence of translation students. We depart from the hypothesis that some students select inapropiate translation strategies when faced with certain translation problems leading them to translation errors. In order to avoid these translation errors originated by wrong application of such strategies we propose a didactic method which helps to prevent them by a) raising awareness of the different subcompetences required while translating, b) improving the ability to identify translation problems and relate them to the different subcompetences and c) enhancing the use of the most adequate strategy according to the characteristics of each problem. With regard to translation and how translation competence is acquired our work follows the communicative approach to translation theory as defended among others by Hatim & Mason (1990), Lörscher (1992) and Kiraly (1995), where translation is seen as a communicative activity which can be analized from a psycholinguistic perspective. In this sense we give operative definitions for what we understand by “translation problem”, “translation strategy”, “translation error”, “translation competence” and “translation”. Our approach to didactics adapts recent developments in Second Language Teaching within the communicative paradigm as is the task based approach by Nunan (1989) acquisition to translation. Fitting the recquirements of this pedagogic approach we present a planning for a translation course which is compatible with present translation studies.

A rotation method which gives linear Lp-Estimates for powers of the Ahlfors-Beurling operator

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Stability of periodic solutions obtained via the averaging method for nonsmooth Lipschitz system

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