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Remo Probst, Larisa Bogdea, Dan S. Bandacu, Mirko Bohuš, Svilen Cheshmedzhiev, Ákos Gáborik, Siegfried Geissler, Calin V. Hodor, Dan T. Ionescu, Veselin Koev, Tibor Mikuska, Zsolt Nagy, Tibor Parrag, Vlatko Rožac, Matthias Schmidt, Thomas Schneider, Marko Šćiban, Sándor Tatai, Emil Todorov, Adrian Tomik, Marko Tucakov, Miklós Váczi and Georg Frank

., Milenkovic- Srbulovic M., Parrag T., Petrova V., Raluca A., Rožac V., Šakić R., Schneider T., Surovec P., Tatai S., Tóth B., Tucakov M., Vasić I., Frank G. (in prep.): Riparian bird species (Little Ringed Plover, Sand Martin) as indicators for river dynamics and morphology. - ICPDR - International Commission for the Protection of the Danube River, Vienna. TERRA CAPI (2014): White Tailed Eagle (Haliaeetus albicilla) wintering population survey along the Duna river and in the Szigetköz area. - Research report by Terra Capi, Cultural and

Open access

Dana Radler

.” Journal of the Short Story in English 41 (2003). Web. 15 May 2013. Fitzgerald, Patrick and Brian Lambkin. Migration in Irish History: 1607-2007 . Basingstoke, Hampshire: Palgrave Macmillan, 2008. Frank, Soren. Migration and Literature: Gunther Grass, Milan Kundera, Salman Rushdie and Jan Kjaerstad . New York: Pagrave Macmillan, 2008. Grinberg, Leon and Rebeca Grinberg. “Psychoanalytic Perspectives on Migration.” Psychoanalysis and Culture: A Kleinian Perspective . Ed. David Bell. London & New York: Karnac, 1999. 154-169. McCarthy, Dermot

Open access

Mareike Trauerstein, Sally E. Lowick, Frank Preusser and Heinz Veit

Abstract

We investigate the suitability of sedimentary quartz associated with former glacial advances in northern Switzerland to provide reliable burial dose estimates using Optically Stimulated Luminescence (OSL). Previous studies on northern alpine quartz show that its signal characteristics can be poor and potentially problematic. We analyse quartz signals of small aliquots, which reveal the presence of a prominent medium or slow component in the initial part of some signals. Nonetheless, rejection of aliquots with unfavourable signal composition does not alter the burial dose estimates, but significantly reduces the data set for De determination. Signal lifetimes from isothermal decay measurements cover a wide range of values, yet the lowest lifetimes are high enough to guarantee a reliable burial dose estimate for samples of < 400 ka. Comparison of small aliquot and single grain burial dose distributions reveals that signal averaging masks partial bleaching in some of the samples. We therefore strongly recommend single grain measurements for samples from this setting and area, in order to exclude age overestimation due to partial bleaching.

Open access

Ingo Gastinger, Frank Meyer, Thomas Lembcke, Uwe Schmidt, Henry Ptok and Hans Lippert

Impact of Fast-Track Concept Elements in the Classical Pancreatic Head Resection (Kausch-Whipple Procedure)

The aim of the study was to determine statistically significant factors with an impact on the early postoperative surgical outcome.

Material and methods. The influence of applied fast-track components on surgical results and early postoperative outcome in 143 consecutive Kausch-Whipple procedure patients was evaluated in a single-center retrospective analysis of a prospective collection of patient-associated pre-, peri- and postoperative data from 1997-2006.

Results. The in-hospital mortality rate was 2.8% (n=4). Fast-track measures were shown to have no effect on the morbidity rate in the multi-variate analysis. Over the study period, a decrease of intraoperative infusion volume from 14.2 mL/kg body weight/h in the first year to 10.7 mL/kg body weight/h in the last year was accompanied by an increase in patients requiring intraoperative catecholamines, up from 17% to 95%. The administration of ropivacain/sufentanil via thoracic peri-dural catheter injection initiated in 2000 and now considered the leading analgesic method, was used in 95% of the cases in 2006. Early extubation rate rose from 16.6% to 57.9%.

Conclusions. Fast-track aspects in the perioperative management have become more important in several surgical procedure even in those with a greater invasiveness such as Kausch-Whipple. However, such techniques used in peri-operative management of Kausch-Whipple pancreatic-head resections had no impact on the morbidity rate. In addition, the low in-hospital mortality rate was particularly attributed to surgical competence.

Open access

Daniel Rufer, Edwin Gnos, Ralph Mettier, Frank Preusser and Guido Schreurs

Abstract

The application of luminescence dating to young volcanic sediments has been first investigated over three decades ago, but it was only with the technical innovations of the last decade that such analyses became viable. While current analytical procedures show promise for dating late Quaternary volcanic events, most efforts have been aimed at unconsolidated volcanic tephra. Investigations into direct dating of lava flows or of non-heated volcanoclastics like phreatic explosion layers, however, remain scarce. These volcanic deposits are of common occurrence and represent important chrono- and volcanostratigraphic markers. Their age determination is therefore of great importance in volcanologic, tectonic, geomorphological and climate studies. In this article, we propose the use of phreatic explosion deposits and xenolithic inclusions in lava flows as target materials for luminescence dating applications. The main focus is on the crucial criterion whether it is probable that such materials experience complete luminescence signal resetting during the volcanic event to be dated. This is argued based on the findings from existing literature, model calculations and laboratory tests.

Open access

Andrej Udelnow, Michael Goertler, Frank Meyer and Zuhir Halloul

Abstract

Primitive carotido-basilar anastomoses (PCA) are persistent fetal vessels. The aim of the study was to compare the clinical characteristics of patients operated on for internal carotid artery (ICA) stenosis with or without PCA in order to evaluate the impact of PCA on the treatment. Material and methods. Consecutive patients operated on for ICA stenosis at our university hospital were included. Surgical treatment consisted in carotid endarterectomy (CEA) with patch plastic. Results. Of the 380 CEA performed between 2006 and 2012, PCA were found in six patients (1.6%). All patients with PCA were symptomatic vs. 54% of patients without PCA (p=0.035). Significantly less posterior collateral flow was present in patients with PCA (33%) compared to those without PCA (85%, p=0.01). Only two of the six patients with PCA were diagnosed prior to surgery, none was ligated intraoperatively. PCA was not associated with stroke and restenosis at long-term follow up. Conclusions. PCA are rarely diagnosed prior to surgery in patients with ICA stenosis and need not to be ligated during CEA

Open access

Olivier Loquineau, Aurélien Caplan, Karine Toumazeau, Christophe Zanetto, Marine Billiot and Frank Goethals

On the Intention to Use an Online Learning Platform Feature

Our research project gives more insight into antecedents of students' intention to use features of an online learning platform. This paper introduces the study year in the UTAUT (Unified Theory of Acceptance and Use of Technology) model. We also include three constructs that are mentioned in literature on student satisfaction with classic (offline) classes. Statistical tests show that new constructs are statistically significant antecedents of the intent of students to use the new feature. Two new constructs seem as important as the most important UTAUT variables performance expectancy and effort expectancy. The R2 of our model is significantly higher than the R2 that is achieved when the classic UTAUT is applied to our dataset.

Open access

Juraj Racko, Miroslav Mikolášek, Peter Benko, Ondrej Gallo, Ladislav Harmatha, Ralf Granzner and Frank Schwierz

Coupled Defect Level Recombination in the P—N Junction

The well known Shockley-Read-Hall (SRH) model considers emission and capture processes at defects exhibiting a single level or multiple non-coupled levels in the band gap of the semiconductor. The present paper generalizes the model to the case of two mutually coupled defect levels acting as trapping centres. If the intercenter transition is not considered, the model reduces to the case of two non-coupled levels treated by the SRH model.

Open access

Andrej Udelnow, Manfred Schönfelder, Peter Würl, Zuhir Halloul, Frank Meyer, Hans Lippert and Paweł Mroczkowski

The aim of the study.

The overall survival (OS) of patients suffering From various tumour entities was correlated with the results of in vitro-chemosensitivity assay (CSA) of the in vivo applied drugs.

Material and methods. Tumour specimen (n=611) were dissected in 514 patients and incubated for primary tumour cell culture. The histocytological regression assay was performed 5 days after adding chemotherapeutic substances to the cell cultures. n=329 patients undergoing chemotherapy were included in the in vitro/in vivo associations. OS was assessed and in vitro response groups compared using survival analysis. Furthermore Cox-regression analysis was performed on OS including CSA, age, TNM classification and treatment course.

Results. The growth rate of the primary was 73-96% depending on tumour entity. The in-vitro response rate varied with histology and drugs (e.g. 8-18% for methotrexate and 33-83% for epirubicine). OS was significantly prolonged for patients treated with in vitro effective drugs compared to empiric therapy (log-rank-test, p=0.0435). Cox-regression revealed that application of in vitro effective drugs, residual tumour and postoperative radiotherapy determined the death risk independently.

Conclusions. When patients were treated with drugs effective in our CSA, OS was significantly prolonged compared to empiric therapy. CSA guided chemotherapy should be compared to empiric treatment by a prospective randomized trial.

Open access

Frank L’Engle Williams, Katherine M. Lane and William G. Anderson

Abstract

Several Neandertals derive from the karstic caves of the Meuse river tributaries of Belgium, including Engis 2, Scladina 4A-4 and Spy 1. These may form a group that is distinct in maxillary first molar occlusal outlines compared to La Quina 5 from Southwest France. Alternatively, chronological differences may separate individuals given that Scladina 4A-4 from MIS 5 is older than the others from MIS 3. Neolithic samples (n = 42) from Belgium (Maurenne Caverne de la Cave, Hastière Caverne M, Hastière Trou Garçon, Sclaigneaux and Bois Madame) dated to 4.6–3.9 kyr provide a context for the Neandertals. Dental casts were prepared from dental impressions of the original maxillary molars. Crown and occlusal areas as well as mesiodistal lengths were measured by calibrated Motic 3.0 microscope cameras. Occlusal outlines of the casts were captured through photostereomicroscopy and non-landmark smooth tracing methods. Occlusal outlines were processed using elliptical Fourier analysis within SHAPE v1.3 which reduced amplitudes of the harmonics into principal components (PC) axes. The first two PC axes group the Neandertals, although Scladina 4A-4 falls nearly outside the convex hull for the Neolithic sample. Neandertals are imperfectly separated from the Neolithic sample on PC3 and PC4, and completely distinct on PC5 and PC6. Scladina 4A-4 differs from the other Neandertals on most PC axes. Chronology may best explain the separation of Scladina 4A-4 from the more recent fossils, and particularly Spy 1 and La Quina 5 which are the most similar in maxillary first molar occlusal outline shape.