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Open access

Frank Preusser, Merle Muru and Alar Rosentau

Abstract

Different post-IR Infrared Stimulated Luminescence (IRSL) approaches are applied to sediments from a Holocene coastal foredune sequence on Ruhnu Island in the eastern Baltic Sea. The comparison of D e-values and ages determined by the different approaches is complimented by fading and bleaching experiments. The fading experiments imply strong fading of IRSL (50°C) signals and no fading of any of the post-IR IRSL signals, but this is not confirmed by the determined D e-values. In fact, post-IR IRSL (150°C) D e-values agree within errors with those calculated for IRSL (50°C). From the bleaching experiments it is inferred that the higher values observed for post-IR IRSL at more elevated stimulation temperatures (225°C/290°C) are likely related to either thermal transfer and/or slow-to-bleach components within the signal. For the dating of the Holocene foredune sequence of Ruhnu Island, the post-IR IRSL (150°C) approach is preferred and these agree with the limited independent age control available from radiocarbon dating. Accordingly, the sequence formed between ca. 7.0 ka and 2.5 ka ago.

Open access

Guenter Weiss, Cora Wex, Hans Lippert, Jens Schreiber and Frank Meyer

Abstract

Fistula development after esophageal resection is considered as one of the most serious postoperative complications.

The authors reported a case on clinical experiences in the postoperative diagnostic and successful therapeutic management of a tracheomediastinal fistula after esophageal resection, using endoscopic application of fibrin glue.

The early approach of an anastomotic insufficiency after esophageal resection because of a squamous cell carcinoma (pT3pN0M0G2) below the tracheal bifurcation including transposition of a re-modelled gastric tube and end-to-side anastomosis 24 hours postoperatively in a 55-year old patient combined i) surgical re-intervention from the periesophageal site (reanastomosis, gastroplication, lavage, local and mediastinal drainage) and, later on, ii) extensive rinsing with consecutive endoscopic fibrin glue application into the tracheal mouth of the subsequently developed tracheomediastinal fistula as a consequence of the inflammatory changes within the surrounding tissue.

In conclusion, this approach was successful and beneficial for the patient's further postoperative course, which was associated with other complications such as pneumonia and acute myocardial infarction. The fistula closed sufficiently and permanently with no further surgical intervention at the tracheal as well as mediastinal site and allowed patient's later discharge with no further complaints or problems.

Open access

Ilaria Torre and Frank Loesche

Abstract

The ability to communicate complex meanings is a specific human ability which plays a crucial role in social interactions. A habitual example of these interactions is conversation. However, we observe that spontaneous conversation often hits an impasse when none of the interlocutors immediately produces a follow-up utterance. The existence of impasses in conversations, and the way that interlocutors overcome them provide evidence for our argument that conversation is a sequence of creative problem solving. In this work we use techniques from Conversation Analysis (CA) on publicly available databases of naturally-occurring speech and we suggest a framework to understand how impasses are reached and overcome. As a result, we hope to reveal yet another instance of the bond between language and creativity.

Open access

Frank J. Nugent, Thomas M. Comyns and Giles D. Warrington

Abstract

The debate over low-volume, high-intensity training versus high-volume, low-intensity training, commonly known as Quality versus Quantity, respectively, is a frequent topic of discussion among swimming coaches and academics. The aim of this study was to explore expert coaches’ perceptions of quality and quantity coaching philosophies in competitive swimming and to investigate their current training practices. A purposeful sample of 11 expert swimming coaches was recruited for this study. The study was a mixed methods design and involved each coach participating in 1 semi-structured interview and completing 1 closed-ended questionnaire. The main findings of this study were that coaches felt quality training programmes would lead to short term results for youth swimmers, but were in many cases more appropriate for senior swimmers. The coaches suggested that quantity training programmes built an aerobic base for youth swimmers, promoted technical development through a focus on slower swimming and helped to enhance recovery from training or competition. However, the coaches continuously suggested that quantity training programmes must be performed with good technique and they felt this was a misunderstood element. This study was a critical step towards gaining a richer and broader understanding on the debate over Quality versus Quantity training from an expert swimming coaches’ perspective which was not currently available in the research literature.

Open access

Juraj Štefanovič and Frank Schindler

Abstract

Aim of the article is to present our research dealing with virtual reality modeling and education activities. It involves a chain of development steps: taking pictures of objects, collecting information, creation of 3D models and panoramas, setting up the interactive virtual reality environment along with educational support and testing the user experience with students. Methodology/methods of work: the creation of 3D models and panoramas is done by taking pictures of real objects and using them as textures. The education materials are created as interactive presentations and the usability testing of these presentations should be planned. Scientific goal is to measure the quality of interaction by this education support in order to derive rules testing effectiveness of support, interactive applications and presentations. Findings: 3D models and other educational support materials may be created voluntarily by teachers. The open source library for many different models should be created by whole community provided suitable interfaces of modeling tools will be arranged. Conclusions: Complex educational and interactive materials including virtual reality and panoramas are satisfactory when combined with easy 3D models that are made from taken pictures, which could be made by teachers themselves and/or open communities by existing cameras.

Open access

Frank Müller, Philip Sollman and Thea Lautenschläger

Abstract

Tortella opaca, an African moss species described from Victoria Falls in Zimbabwe, is taxonomically assessed and stated to be conspecific with Neotropical Weissia jamaicensis. A lectotype of Tortella opaca is selected. The discovery of Weissia jamaicensis in Uíge Province, northern Angola, and in Lusaka Province, Zambia, is reported. Diagnostic features of W. jamaicensis are given in relation to similar species and are illustrated, and the phytogeographic importance of its records in the Palaeotropics is highlighted.

Open access

Frank van der Velde

Abstract

The ability to learn constructions may be important for the development of a self-organizing architecture for artificial general intelligence. Constructions are structural relations between more specific or more abstract conceptual representations. They can be derived from the processes of alignment, collocations and distributed equivalences. An architecture that integrates in situ grounded representations with cognitive productivity is ideally suited to learn constructions. This paper described such an architecture, based on neuronal assembly structures and neuronal ’blackboards’ for grounded compositional representations. The paper outlines how constructions could be learned in such an architecture and how the architecture could eventually develop into an autonomous self-organizing architecture for artificial general intelligence.

Open access

Frank Miller, Walter J. Freeman and R. L. Stedman

Abstract

A large number of cigarette additives was tested for the effect on the combustion temperature, including free radical initiators and inhibitors, salts of organic acids, inorganic salts and other inorganic compounds, lead-borate glasses, oxidizing agents, petroleum refining and oxidative catalysts, flame retardants, fire-proofing salts and other compounds and mixtures. Most of the additives showed no dramatic increase or decrease of temperature even at high concentrations but some indications of small alterations were obtained in a few cases.

Open access

Jőrg Arend, Doerthe Kuester, Albert Roessner, Hans Lippert and Frank Meyer

Both gastrointestinal stromal tumors (GIST) and liposarcoma originate from mesenchymal tissue. Their coincidence requires a specific expertise in the diagnostic and therapeutic management.

An unusual exemplary case is described representing a 47-year old female patient with a gastric GIST and a monstrous retroperitoneal liposarcoma with infiltration of the left kidney. The gastric tumor lesion was removed with a tangential resection of the gastric wall; the retroperitoneal tumor lesion was resected including the left kidney. Both tumors were resected with no macroscopic tumor residual. The technically difficult surgical intervention did not show any postoperative complication, and the postoperative course was also uneventful. The complete tumor resection is the treatment of choice in mesenchymal tumors (aim: R0). Depending on histologic tumor classification, resection status and tumor sensitivity, a subsequent radiation and/or chemotherapy is necessary, which allowed to achieve a postoperative tumor-free survival of 6 years including a good quality of life.

Open access

Dorian Gaar, Sally Lowick and Frank Preusser

Abstract

Luminescence properties of two samples taken from sand lenses in proglacial outwash de-posits of a piedmont glacier that reached the Swiss midlands during the Last Glacial Maximum are investigated in detail. Deconvolution of CW-OSL decay curves shows that the fast component dominates the OSL signal of quartz. The chemistry of single feldspar grains, in particular the K content in different grains, is determined using wavelength dispersive spectrometry (electron microprobe), revealing an average 12.9 wt.% K of the grains contributing to the IRSL signal. D e distributions are investigated in order to gain insights into partial bleaching, and agreement is found for quartz OSL and feldspar IR50 and pIRIR225 ages for small aliquots and single grains when applying the Minimum Age Model. These ages are also consistent with independent age control. For one sample, ages determined using the Central Age Model result in highly overestimated ages for both feldspar and quartz.