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Soziale und vereinseigene Medien sowie auch kostenpflichtige Angebote im Feld verändern die Zuschreibungen journalistischer Kriterien aufseiten des Publikums. Die Teilnahme an einer Diskussion zu sportjournalistischen Themen ist derzeit sehr hoch. Anhand der Theorie des boundary works soll herausgefunden werden, wie der Sportjournalismus, mit dessen klassischen und alternativen Formate sowie die Partizipationsmöglichkeiten von den Rezipient*innen wahrgenommen werden. In der Literatur ist die Meinung vorherrschend, dass Rezipient*innen unter anderem eine aktuelle und sachliche Berichterstattung zu den Merkmalen des sportjournalistischen Bereichs zählen. Hinsichtlich der alternativen Medien sind das Vorhandensein persönlicher Sichtweisen, Hintergrundberichte sowie viele Interaktionsmöglichkeiten wesentliche Bestandteile. Anhand der Durchführung von qualitativen Leitfadeninterviews mit 13 Teilnehmer*innen zeigt sich auch hier, dass eine neutrale Berichterstattung über den Sport für die Teilnehmer*innen zwar ein wesentliches Merkmal des Sportjournalismus darstellt, eine emotionale und parteiische Darstellung der Sportthemen aber nicht weniger bedeutend erscheint. Alternative Medienformate des Sportjournalismus bieten für die Rezipient*innen neben Randsportarten, mehr Hintergründe und agieren partizipativer als klassische Medien. Von den klassischen Medien erwarten sich die Rezipient*innen eine kritische und neutrale Berichterstattung der Sportthemen. Außerdem ist erkennbar, dass auf Instagram für die Rezipierenden die Teilnahme an sportjournalistischen Diskussionen, im Gegensatz zu den klassischen Medien, denen wenige Möglichkeiten hinsichtlich einer Diskussionsteilnahme attestiert werden, gegeben ist. Damit Sportjournalist*innen von den Rezipient*innen auch als jene legitimiert werden, sollten sie auf eine neutrale Berichterstattung mit dennoch unterhaltenden Aspekten Wert legen. Besonders für die Anerkennung klassischer Medien des Sportjournalismus spielt diese kritische und neutrale Perspektive eine wichtige Rolle. Für die Zuschreibung als alternative Sportmedien aufseiten der Rezipient*innen sind für Sky & Co. individuelle Meinungen so wie unzählige Partizipationsmöglichkeiten, die sie auf den klassischen Sportmedien kaum vorfinden, von großer Bedeutung., Social and club-owned media as well as paid services in the field are changing the attributions of journalistic criteria for the audience. Participation in a discussion on sports journalism topics is currently very high. The theory of boundary works will be used to find out how sports journalism, with its classic and alternative formats, and the opportunities for participation are perceived by the recipients. The prevailing opinion in the literature is that recipients consider up-to-date and factual reporting to be one of the characteristics of sports journalism. Concerning alternative media, the presence of personal perspectives, background reports and many opportunities for interaction are essential elements. Based on qualitative guideline interviews with 13 participants, it is also evident here that neutral reporting on sports is an essential characteristic of sports journalism for the participants, but an emotional and biased presentation of sports topics does not appear to be less important. Alternative media formats of sports journalism offer recipients more background information besides marginal sports and act more participatory than classic media. The recipients expect critical and neutral reporting of sports topics from the classic media. It is also apparent that on Instagram, recipients can participate in sports journalistic discussions, in contrast to the classic media, which are said to have few opportunities to participate in discussions. For sports journalists to be legitimised as such by the recipients, they should attach importance to neutral reporting with nevertheless entertaining aspects. This critical and neutral perspective plays an important role, especially in the recognition of classic sports journalism media. For Sky & Co. to be attributed as alternative sports media for the recipients, individual opinions as well as countless opportunities for participation, which they hardly find in the classic sports media, are of great importance.

Oxygen isotope compositions in enamel bioapatite are considered as robust proxy archives for ingested drinking water, body temperature and physiology of fossil vertebrates. However, only few alteration experiments have tested this assumption. Here we present the results of alteration experiments of dental tissues. Three mm-sized dental cubes, comprising both enamel and dentine, were cut from a modern African elephant molar and placed into acidic aqueous solution highly enriched in 18O (3.43 mols/mol%) and were reacted in sealed Teflon vials at temperatures of 30 to 90 °C for up to two months. The δ18OSIMS distribution across the reacted dental cubes were measured in-situ to determine the degree of bioapatite alteration via profiles with step distance as short as 20 μm. In the 30 °C experiments only a few permil enrichment in δ18OSIMS occurred at the outer and inner enamel rim. In contrast, for 90 °C experiments enamel was strongly enriched (≈ 100 to 600 ‰) throughout the complete enamel transect, increasing with experimental duration. The 18O-enriched tracer solution penetrated the enamel and exchanged significant amounts of oxygen with all three different oxygen-bearing moieties PO4, CO3 and OH. Thus, even mm-thick mammalian enamel is susceptible to pervasive oxygen isotope alteration, including the PO4-group, which is generally considered to be robust against abiogenic low temperature oxygen isotope exchange. This has implications for the reliability of enamel δ18O values as palaeoclimatic and palaeoecologic proxy.

Additional file 2: Methods.

Strontium isotopes in biogenic apatite, especially enamel, are widely employed to determine provenance and track migration in palaeontology and archaeology. Body tissues record the 87Sr/86Sr of bioavailable Sr of ingested food and water. To identify non-local individuals, knowledge of the 87Sr/86Sr of a non-migratory population is required. However, varying factors such as tissue turnover rates, feeding selectivity, Sr content, digestibility of food, and the ingestion of mineral dust can influence body tissue 87Sr/86Sr. To evaluate the Sr contribution of diet and water to mammalian hard tissues 87Sr/86Sr, controlled feeding studies are necessary. Here we present 87Sr/86Sr from controlled feeding experiments with two rodent species (Rattus norvegicus, Cavia porcellus). Due to the continuous and fast incremental growth of rat and guinea pig incisors (∼0.1 – 0.5 mm/day), their enamel is expected to record isotopic dietary changes. For Experiment-1: Diet Switch, animals were switched from their respective supplier food to a pelleted experimental diet containing either insect-, plant-, or meat-meal and a staggered-sampling approach was used to monitor the 87Sr/86Sr changes in rat incisor enamel and bone over the course of the experiment. In Experiment-2: Basic Diets, separated cohorts (n = 6) of rats and guinea pigs were fed one of the three pelleted diets and received tap water for 54 days. While the rat incisors showed a complete tissue turnover, the slower-growing guinea pig incisors partially retained supplier diet-related isotopic compositions. In addition, one group of rats fed plant-meal pellets received Sr-rich mineral water, demonstrating that drinking water can be an important Sr source in addition to diet. Additionally, a leaching experiment showed that only a small fraction of diet-related Sr is bioavailable. Finally, in Experiment-3: Dust Addition, guinea pigs were fed pellets with and without addition of 4% of isotopically distinct dust (loess or kaolin). Animals that received kaolin-containing pellets displayed increased enamel 87Sr/86Sr. Intra-population 87Sr/86Sr variability within each feeding group was small and thus we conclude that it should not affect interpretations of 87Sr/86Sr in provenance studies. However, the differences between bulk food and leachate 87Sr/86Sr highlight the importance of Sr bioavailability for provenance studies and Sr isoscapes.

Dissertation, Universität Duisburg-Essen, 2018

Mutations in the gene NPHS2 are the most common cause of hereditary steroid-resistant nephrotic syndrome. Its gene product, the stomatin family member protein podocin represents a core component of the slit diaphragm, a unique structure that bridges the space between adjacent podocyte foot processes in the kidney glomerulus. Dislocation and misexpression of slit diaphragm components have been described in the pathogenesis of acquired and hereditary nephrotic syndrome. However, little is known about mechanisms regulating cellular trafficking and turnover of podocin. Here, we discover a three amino acids-comprising motif regulating intracellular localization of podocin in cell culture systems. Mutations of this motif led to markedly reduced degradation of podocin. These findings give novel insight into the molecular biology of the slit diaphragm protein podocin, enabling future research to establish the biological relevance of podocin turnover and localization.

Bremer, Claudia [Hrsg.]; Krömker, Detlef [Hrsg.]: E-Learning zwischen Vision und Alltag: zum Stand der Dinge. Münster [u.a.] : Waxmann 2013, S. 277-289. - (Medien in der Wissenschaft; 64), Bezug nehmend auf das Hauptziel von Classroom-Response-Systems (CRS) – der Förderung der Interaktion in Massenlehrveranstaltungen – wird im vorliegenden Beitrag die Evaluation eines mobilen CRS namens SMILE dargestellt und diskutiert. Die Ergebnisse zeigen, dass die Funktionalitäten der SMILE-App – Live-Feedback, Quizfragen und Question&Answer – von den Studierenden der Pilotvorlesung unterschiedlich häufig genutzt wurden. Darüber hinaus wurden die Akzeptanz der Studierenden gegenüber dem Einsatz des Tools und die Wirkung der Quizfragen untersucht. Es zeigt sich, dass Schwächen der technischen Ausstattung im Hörsaal und die technische Zuverlässigkeit der SMILEApp wesentliche Einflussfaktoren auf die Nutzungshäufigkeit sein könnten. Im Sinne einer formativen Evaluation konnten nicht nur technische Problembereiche identifiziert werden, sondern auch Ableitungen für das didaktische Konzept der SMILE-unterstützten Vorlesungen gemacht werden. (DIPF./Orig.)

Untersuchung der Selbst- und Fremdeinschätzung bei gesunden Älteren mit subjektiven kognitiven Defiziten mit einer neu entwickelten validierten und ökonomischen alltagsnahen Testbatterie zu verschiedenen Hypothesen. Selbst-und Fremdeinschätzung stimmen bei erhöhter Depressivität nicht überein. Depressive Probanden schätzen sich in neuropsychologischen Tests schlechter ein, als sie es in den objektiven Tests sind. Die Fremdeinschätzung der Gedächtnisleistung ist ein valides Aussenkriterium und stimmt mit den Testergebnissen gut überein.

Untersuchung der Selbst- und Fremdeinschätzung bei gesunden Älteren mit subjektiven kognitiven Defiziten mit einer neu entwickelten validierten und ökonomischen alltagsnahen Testbatterie zu verschiedenen Hypothesen. Selbst-und Fremdeinschätzung stimmen bei erhöhter Depressivität nicht überein. Depressive Probanden schätzen sich in neuropsychologischen Tests schlechter ein, als sie es in den objektiven Tests sind. Die Fremdeinschätzung der Gedächtnisleistung ist ein valides Aussenkriterium und stimmt mit den Testergebnissen gut überein.

State-of-the-art automatic speech recognition (ASR) techniques are typically based on hidden Markov models (HMMs) for the modeling of temporal sequences of feature vectors extracted from the speech signal. At the level of each HMM state, Gaussian mixture models (GMMs) or artificial neural networks (ANNs) are commonly used in order to model the state emission probabilities. However, both GMMs and ANNs are rather rigid, as they are incapable of adapting to variations inherent in the speech signal, such as inter- and intra-speaker variations. Moreover, performance degradations of these systems are severe in the case of unmatched conditions such as in the presence of environmental noise. A lot of research effort is currently being devoted to overcoming these problems. The principal objective of this thesis is to explore new approaches towards a more robust and adaptive modeling of speech. In this context, different aspects of the modeling of speech data with HMMs and GMMs are investigated. Particular attention is given to the modeling of correlation. While correlation between different feature vectors (corresponding to temporal correlation) is typically modeled by the HMM, correlation between feature vector components (e.g., correlation in frequency) is modeled by the GMM part of the model. This thesis starts with the investigation of two potential ways to improve the modeling of correlation, consisting of (1) a shift of the modeling of temporal correlation towards GMMs, and (2) the modeling of correlation within each feature vector by a particular type of HMM. This leads to the development of a novel approach, referred to as ÒHMM2Ó, which is a major focus of this thesis. HMM2 is a particular mixture of hidden Markov models, where state emission probabilities of the temporal (primary) HMM are modeled through (secondary) state-dependent frequency-based HMMs. Low-dimensional GMMs are used for modeling the state emission probabilities of the secondary HMM states. Therefore, HMM2 can be seen as a generalization of conventional HMMs, which they include as a particular case. HMM2 may have several advantages as compared to standard systems. While the primary HMM performs time warping and time integration, the secondary HMM performs warping and integration along the frequency dimension of the speech signal. Frequency correlation is modeled through the secondary HMM topology. Due to the implicit, non-linear, state-dependent spectral warping performed by the secondary HMM, HMM2 may be viewed as a dynamic extension of the multi-band approach. Moreover, this frequency warping property may result in a better, more flexible modeling and parameter sharing. After an investigation of theoretical and practical aspects of HMM2, encouraging recognition results for the case of speech degraded by additive noise are given. Due to the spectral warping property of HMM2, this model is able to extract pertinent structural information of the speech signal, which is reflected in the trained model parameters. Consequently, such an HMM2 system can also be used to explicitly extract structures of a speech signal, which can then be converted into a new kind of ASR features, referred to as ÒHMM2 featuresÓ. In fact, frequency bands with similar characteristics are supposed to be emitted by the same secondary HMM state. The warping along the frequency dimension of speech thus results in an adaptable, data-driven frequency segmentation. In fact, as it can be assumed that different secondary HMM states model spectral regions characterized by high and low energies respectively, this segmentation may be related to formant structures. The application of HMM2 as a feature extractor is investigated, and it is shown that a system combining HMM2 features with conventional noise-robust features yields an improved speech recognition robustness. Moreover, a comparison of HMM2 features with formant tracks shows a comparable performance on a vowel classification task.

Die Messung der transepithelialen Potenzialdifferenz (PD) stellt ein wichtiges Hilfsmittel im Rahmen der Mukoviszidosediagnostik- und Forschung dar. Zur Zeit wird die transepitheliale Potenzialdifferenzmessung nur an wenigen Mukoviszidose-Zentren durchgeführt. Gründe hierfür sind der komplizierte Versuchsaufbau und die aufwändige Wartung. Ziel der vorliegenden Arbeit war es, den Versuchsaufbau und den Messvorgang zu vereinfachen. Ferner sollte geklärt werden, ob die PD-Messung an der Rektalschleimhaut ebenso aussagekräftig ist wie die nasale Messung.

Die Messung der transepithelialen Potenzialdifferenz (PD) stellt ein wichtiges Hilfsmittel im Rahmen der Mukoviszidosediagnostik- und Forschung dar. Zur Zeit wird die transepitheliale Potenzialdifferenzmessung nur an wenigen Mukoviszidose-Zentren durchgeführt. Gründe hierfür sind der komplizierte Versuchsaufbau und die aufwändige Wartung. Ziel der vorliegenden Arbeit war es, den Versuchsaufbau und den Messvorgang zu vereinfachen. Ferner sollte geklärt werden, ob die PD-Messung an der Rektalschleimhaut ebenso aussagekräftig ist wie die nasale Messung.

The purpose of this paper is to investigate the behavior of HMM2 models for the recognition of noisy speech. It has previously been shown that HMM2 is able to model dynamically important structural information inherent in the speech signal, often corresponding to formant positions/tracks. As formant regions are known to be robust in adverse conditions, HMM2 seems particularly promising for improving speech recognition robustness. Here, we review different variants of the HMM2 approach with respect to their application to noise-robust automatic speech recognition. It is shown that HMM2 has the potential to tackle the problem of mismatch between training and testing conditions, and that a multi-stream combination of (already noise-robust) cepstral features and formant-like features (extracted by HMM2) improves the noise robustness of a state-of-the-art automatic speech recognition system.

This report investigates the HMM2 approach recently introduced in the framework of automatic speech recognition. HMM2 can be seen as a mixture of HMMs, where a conventional primary HMM (processing a time series of speech data) is supported on a lower level by a secondary HMM, working along the frequency dimension of a temporal segment of speech. The application of HMM2 to the speech signal is motivated by numerous potential advantages. However, speech recognition results did not show the expected performance improvements. In this paper, the HMM2 approach is pragmatically analyzed and evaluated on speech data, revealing some problems and suggesting potential solutions.

As recently introduced, an HMM2 can be considered as a particular case of an HMM mixture in which the HMM emission probabilities (usually estimated through Gaussian mixtures or an artificial neural network) are modeled by state-dependent, feature-based HMM (referred to as frequency HMM). A general EM training algorithm for such a structure has already been developed. Although there are numerous motivations for using such a structure, and many possible ways to exploit it, this paper will mainly focus on one particular instantiation of HMM2 in which the frequency HMM will be used to extract formant structure information, which will then be used as additional acoustic features in a standard Automatic Speech Recognition (ASR) system. While the fact that this architecture is able to automatically extract meaningful formant information is interesting by itself, empirical results will also show the robustness of these features to noise, and their potential to enhance state-of-the-art noise-robust HMM-based ASR.

State-of-the-art Automatic Speech Recognition (ASR) systems make extensive use of Hidden Markov Models (HMMs), characterized by flexible statistical modeling, powerful optimization (training) techniques and efficient recognition algorithms. When allowed by the software implementation, their flexibility can also be fully exploited in research, by testing various topologies, acoustic units, parameterization schemes, etc. Unfortunately, these HMM systems still suffer from an excessive sensitivity to the variability generally observed in real acoustic environments, including speaker, channel and noise characteristics. In an attempt to tackle this problem, IDIAP recently introduced a new form of HMM, referred to as HMM2, exhibiting numerous potential advantages, which could result in improved robustness of current speech recognition systems. HMM2 can be described as a mixture of HMMs where the HMM emission probabilities (usually estimated by Gaussian Mixtures or a neural network) are themselves estimated by state-specific HMMs working along the acoustic features. Among other properties, it is believed that such HMM2 approach could better model the time/frequency speech flow, including better modeling of the feature correlation. After a brief reminder of the HMM theory, this report first introduces the theoretical basis of HMM2, including their parameterization schemes and the estimation of their parameters through a generalized form of the Expectation-Maximization (EM) training algorithm. It is also the goal of the present report to describe the functionalities and specifications of a new software able to handle, in a flexible way, different forms of HMM and HMM2 topologies and training schemes.

While a lot of progress has been made during the last years in the field of Automatic Speech recognition (ASR), one of the main remaining problems is that of robustness. Typically, state-of-the-art ASR systems work very efficiently in well-defined environments, e.g. for clean speech or known noise conditions. However, their performance degrades drastically under different conditions. Many approaches have been developed to circumvent this problem, ranging from noise cancellation to system adaptation techniques. This paper investigates the influence of using additional information from relatively long timescales to noise robustness. The multiple timescale feature combination approach is introduced. Experiments show that, while maintaining recognition performance for clean speech, robustness could be improved in noisy conditions.