Elektrophysiologische Effekte der slim straight intracochlearen Elektrodenposition

Introduction: Cochlear implantation is the treatment of choice for patients with profound-to-severe sensorineural hearing loss who retain residual hearing. The electrical current distribution of a cochlear implant electrode array is essential for an optimal postoperative hearing benefit. Placement of an electrode contact in a lateral or medial direction to the modiolus is possible with a slim straight electrode design. The electrophysiological effect of this different contact position appears to be unknown. Objective: Our goal is to investigate the electrophysiological effects with different intracochlear electrode contact positions. Study design: Retrospective clinical and descriptive experimental Setting: Tertiary referral center. Material and Methods: A slim straight electrode was inserted into the cochleae of five patients (two female and three male) and the neural response thresholds (NRT’s) were measured in a lateral and medial directed contact position. Additionally, the cochleae in five temporal cadaveric bones were de-capped to allow for in-vitro direct observation of the inserted slim straight electrode contact position, either in a lateral versus medial position. Results: There was no significant difference in NRT’s between lateral versus medial contact position. While the in-vitro temporal bone study indicated no intracochlear torsion behaviour within the lateral or medial electrode contact position. Conclusion: Our results suggest that the intracochlear positioning of a slim straight electrode does not affect NRT’s.Einleitung: Cochleaimplantate ist die Behandlung der Wahl für Patienten mit hoch bis schwergradiger Innenohrschwerhörigkeit, die noch Resthörvermögen haben. Die elektrische Stromverteilung innerhalb der Cochlea durch eine Cochlea- Implantatelektrode ist für eine optimale postoperative Hörleistung entscheidend. Eine Slim Straight Elektrode ermöglicht die Platzierung der Elektrodenkontakte in lateraler oder medialer Richtung zum Modiolus. Die elektrophysiologische Wirkung dieser unterschiedlichen Kontaktrichtungen erscheint bisher unbekannt. Studienziel: Das Ziel dieser Studie war es, den Einfluss der intracochlearen lateralen oder medialen Elektrodenplatzierung auf das elektrophysiologische Verhalten zu untersuchen. Studiendesign: Retrospektive klinisch und deskriptiv experimentelle Studienort: überregionales Krankenhaus der Maximalversorgung. Material und Methoden: Eine slim-straight Elektrode wurde in die Cochlea von fünf Patienten (zwei weibliche und drei männliche) eingeführt und die daraus resultierende Neural Response Thresholds (NRT’s) in lateral sowie medial ausgerichteter Kontaktposition gemessen. Außerdem erfolgte einer in-vitro Untersuchung der Cochlea (de-capping) aus dem Felsenbein von insgesamt fünf Spendern. So konnte die Insertionsverhalten der jeweiligen Elektrodenkontaktposition (lateral gegenüber medial) beobachtet / ausgewertet werden. Ergebnisse: Es zeigten sich keine signifikante Unterschiede in den NRT‘s zwischen der lateralen und der medialen Position der Elektrodenkontakte. Die in-vitro Felsenbeinstudie konnte kein intracochleares Torsionsverhalten der Elektrode innerhalb der lateralen oder medialen Positionierung nachweisen. Fazit: Die Ergebnisse deuten darauf hin, dass die intracochleare Position von Slim Straight Elektroden die NRT‘s nicht beeinflusst

Unemployment and common smooth transition trends in central and eastern european countries

In this paper we analyse whether the apparent comovement of unemployment rates for some of the Central and Eastern EU new members can be explained by a common force, possibly linked to the process of economic integration. For this purpose we test for nonlinear unit roots as a first step to testing for common nonlinearities. Our results show that for five countries, out of eight, unemployment dynamics appear to be well described as a stationary process around highly persistent structural changes. Furthermore, we find evidence of a common nonlinear component driving the unemployment rates

Oil prices and unemployment in the UK before and after the crisis: A Bayesian VAR approach. A note.

The aim of this paper is to analyse the role of oil price movements in the evolution of unemployment in the UK, accounting for asymmetric effects. Distinguishing between positive and negative innovations in oil prices allows us to provide policy insights. Estimating Bayesian SVARs, we find that the relationship between oil prices and unemployment in the UK differs before and after the beginning of the Great Recession. We also find that negative oil price innovations have contributed positively to preventing further rises in unemployment after the start of the crisis in 2008

Social Exclusion and Convergence in the EU: An Assessment of the Europe 2020 Strategy

Economic convergence has long been a declared objective of the EU and considered the fundamental mechanism for achieving socioeconomic cohesion. The recent economic crisis had an uneven impact across EU countries and brought a halt to the process of economic and social convergence. In response to this situation, the Europe 2020 strategy, launched in 2010, aimed to deliver social and territorial cohesion in the Member States. In this paper we evaluate the poverty and social exclusion pillar of the Europe 2020 strategy by analysing whether it has promoted convergence across the EU countries in the indicators devised to capture risk of poverty, severe material deprivation, and the number of persons living in households with very low work intensity. Our results for all three rates indicate that convergence occurs in heterogeneous clubs that do not follow a geographic east‒west or south‒north pattern. Convergence within each club, especially for the severe deprivation rate, takes place by means of a catching-up process, with Eastern European levels converging on the Western levels. Finally, not only is there club convergence, but there is no tendency for the clubs to convergence. Poverty and social cohesion indicators show a multi-speed Europe, casting doubt on the sustainability of the overall convergence process in the EU

The effect of the EMU on short and long-run stock market dynamics: New evidence on financial integration

This paper deals with the time evolution of stock market integra- tion around the introduction of the euro. In particular we test whether the degree of integration between the main eurozone countries increased after European monetary union. The contribution of the paper to the extant literature is twofold: a) first, we take into account the poten- tial long-run equilibrium relationship between stock indices allowing for structural changes in the cointegration space that might capture the ef- fect of the introduction of the euro, and b)we formally test the existence of greater financial integration after European monetary union across the main member countries and between these members and the UK. Empirical evidence reveal the existence of long-run equilibrium relation- ships between European stock markets even before the introduction of the euro. Our empirical findings suggest that financial integration is not the direct consequence of the removal of exchange rate risk due to currency unification. Rather, it arises as a result of macroeconomic con- vergence. This aspect is corroborated by the nature of the principal component structure of estimated conditional correlations

Nonlinear trend stationarity of the Real Exchange Rates of Mediterranean countries

The aim of this article is to provide additional evidence on the fulfillment of the Purchasing Power Parity hypothesis in the so-called Mediterranean countries. In order to test for the empirical validity of such hypothesis, we have applied two types of unit root tests. The first group is due to Bierens (1997) who generalizes the alternative hypothesis to nonlinear trend stationariry and, the second is the Leybourne, Newbold and Vougas (1998) approach that uses a nonlinear specification for the intercept and slope in order to detrend the series. The results suggest a pretty weak evidence in favour of the Purchasing Power Parity hypothesis for this group of countrie

Unit Labour Costs and the Dynamics of Output and Unemployment in the South ern European Crisis Countries

The GIPS countries, the south ern European crisis countries, have seen depressed output dynamics and high unemployment rates during the great recession following the 2007 - 2008 financial crisis . Th is paper considers the effects of measures that seek to improve competitiveness by reducing real unit labour costs. The results are deriv ed in structural vector autoregressive models for each of t he GIPS counties as well as two reference countries , Germany and the Netherlands. The responses of output and unemployment to innovations in real unit labour costs are economically and statistically significant for Germany and the Netherlands, whereas the responses are typically muted and imprecise estimated for the GIPS countries. The small and uncertain effects raise doubts regarding the efficacy of measures that seek to lower real unit labour costs in the GIPS countrie

Automated Network Service Scaling in NFV: Concepts, Mechanisms and Scaling Workflow

Next-generation systems are anticipated to be digital platforms supporting innovative services with rapidly changing traffic patterns. To cope with this dynamicity in a cost-efficient manner, operators need advanced service management capabilities such as those provided by NFV. NFV enables operators to scale network services with higher granularity and agility than today. For this end, automation is key. In search of this automation, the European Telecommunications Standards Institute (ETSI) has defined a reference NFV framework that make use of model-driven templates called Network Service Descriptors (NSDs) to operate network services through their lifecycle. For the scaling operation, an NSD defines a discrete set of instantiation levels among which a network service instance can be resized throughout its lifecycle. Thus, the design of these levels is key for ensuring an effective scaling. In this article, we provide an overview of the automation of the network service scaling operation in NFV, addressing the options and boundaries introduced by ETSI normative specifications. We start by providing a description of the NSD structure, focusing on how instantiation levels are constructed. For illustrative purposes, we propose an NSD for a representative NS. This NSD includes different instantiation levels that enable different ways to automatically scale this NS. Then, we show the different scaling procedures the NFV framework has available, and how it may automate their triggering. Finally, we propose an ETSI-compliant workflow to describe in detail a representative scaling procedure. This workflow clarifies the interactions and information exchanges between the functional blocks in the NFV framework when performing the scaling operation.Comment: This work has been accepted for publication in the IEEE Communications Magazin