Using Multi-Sense Vector Embeddings for Reverse Dictionaries

Popular word embedding methods such as word2vec and GloVe assign a single vector representation to each word, even if a word has multiple distinct meanings. Multi-sense embeddings instead provide different vectors for each sense of a word. However, they typically cannot serve as a drop-in replacement for conventional single-sense embeddings, because the correct sense vector needs to be selected for each word. In this work, we study the effect of multi-sense embeddings on the task of reverse dictionaries. We propose a technique to easily integrate them into an existing neural network architecture using an attention mechanism. Our experiments demonstrate that large improvements can be obtained when employing multi-sense embeddings both in the input sequence as well as for the target representation. An analysis of the sense distributions and of the learned attention is provided as well

The Challenge of Transcultural Competence: Background Reading of Target Culture Current Events Articles

At the lower and intermediate-levels of language instruction, students do not have sufficient language proficiency to inform themselves about current events in the target language. Knowledge of current events is an important part of cultural competence and should not be absent from instruction because of linguistic restrictions. This article proposes to remedy this problem, by creating out-of-class reading assignments of current events articles from US and international English language news sources. The article provides practical information on selection criteria for articles, suggests news sources, and gives examples of assignments

Mark Twain and The Awful German Language

The article analyses Mark Twain\u27s 1869 essay The Awful German Language in terms of Twain\u27s comments on morphological, syntactical, lexical and phonological feature of German. The topic is presented in the context of Twain\u27s German language learning experience. Relevance of the article for German language instruction today is also discussed

Molecular characterization of Ptf1a activity during Xenopus embryogenesis

Für die Bildung eines funktionalen Nervensystems in Vertebraten ist ein Gleichgewicht zwischen inhibitorischen und exzitatorischen Neuronen essentiell. Ein Schlüsselfaktor in der Regulation dieses Gleichgewichts ist der bHLH Transkriptionsfaktor Ptf1a, welcher GABAerge inhibitorische Neurone in der Retina, dem Hinterhirn und im Rückenmark von Vertebraten spezifiziert, zugleich jedoch glutamaterge exzitatorische Neurone unterdrückt. In diesem Zusammenhang benötigt die Aktivität von Ptf1a die Bildung eines trimeren Komplexes, in welchem Ptf1a an ein allgemein exprimiertes E-Protein und an ein Mitglied der Su(H)-Familie bindet. Ptf1a fördert ebenfalls generelle neuronale Differenzierung in X. laevis Embryonen und Explantaten, was darauf hinweist, dass Ptf1a proneurale Aktivität besitzt. In dieser Doktorarbeit wurde die Rolle von Ptf1a im Zusammenhang mit genereller Neurogenese (frühe Funktion) und neuronaler Subtypen-Spezifizierung (späte Funktion) untersucht. Durch eine zeitliche Expressionsanalyse bekannter Gene konnte gezeigt werden, dass Ptf1a durch die Aktivierung von nachgeschalteten Genen, ähnlich dem proneuralen Transkriptionsfaktor Ngn2, in animalen Kappen (naives Ektoderm) zu frühen Zeitpunkten Neurogenese induziert. In späteren Stadien hingegen aktivierte Ptf1a die Expression von Markergenen, die GABAerge Neurone kennzeichnen, während neuronale glutamaterge Markergene von Ngn2 induziert wurden. Eine mutierte Version von Ptf1a (Ptf1aW224A/W242A), welche nicht in der Lage ist, mit dem Kofaktor Su(H) zu interagieren, behielt die Fähigkeit, generelle Neurogenese zu induzieren, nicht aber GABAerge Markergene zu aktivieren. Diese Ergebnisse lassen darauf schließen, dass Ptf1a in der Entwicklung des Nervensystems kontext-spezifische Transkriptionskomplexe bildet: einen Su(H)-unabhängigen Komplex zur Aktivierung genereller Neuorgenese und einen Su(H)-abhängigen Komplex zur Spezifizierung GABAerger Neurone. Da die Zielgene von Ptf1a in der Entwicklung des Nervensystems nicht genau bestimmt sind, wurden zwei unabhängige Transkriptom-Analysen durchgeführt, um das Ptf1a nachgeschaltete genetische Netzwerk aufzuzeigen. In diesen Untersuchungen wurde eine zeitliche Analyse von Genen durchgeführt, die durch wildtyp Ptf1a, Ptf1aW224A/W242A und Ngn2 in X. laevis animalen Kappen aktiviert werden; direkte Zielgene für Ptf1a und Ptf1a/Su(H) wurden bestimmt durch die Aktivierung dieser Transkriptionsfaktoren unter Vorhandensein eines Proteinsyntheseinhibitors (CHX). Durch dieses Vorgehen konnten viele mutmaßlich neue frühe und späte Zielgene von Ptf1a identifiziert werden. Eine weitere Analyse dieser nachgeschalteten Zielgene dürfte darüber Aufschluss geben, wie Ptf1a generelle Neurogenese und neuronale Subtypen-Spezifizierung reguliert

Weak supervision and label noise handling for Natural language processing in low-resource scenarios

The lack of large amounts of labeled data is a significant factor blocking many low-resource languages and domains from catching up with recent advancements in natural language processing. To reduce this dependency on labeled instances, weak supervision (semi-)automatically annotates unlabeled data. These labels can be obtained more quickly and cheaply than manual, gold-standard annotations. They also, however, contain more errors. Handling these noisy labels is often required to leverage the weakly supervised data successfully. In this dissertation, we study the whole weak supervision pipeline with a focus on the task of named entity recognition. We develop a tool for automatic annotation, and we propose an approach to model label noise when a small amount of clean data is available. We study the factors that influence the noise model's quality from a theoretic perspective, and we validate this approach empirically on several different tasks and languages. An important aspect is the aim for a realistic evaluation. We perform our analysis, among others, on several African low-resource languages. We show the performance benefits that can be achieved using weak supervision and label noise modeling. But we also highlight open issues that the field still has to overcome. For the low-resource settings, we expand the analysis to few-shot learning. For classification errors, we present a novel approach to obtain interpretable insights of where classifiers fail.Der Mangel an annotierten Daten ist ein wesentlicher Faktor, der viele Sprachen und Domänen mit geringen Ressourcen daran hindert, mit den jüngsten Fortschritten in der digitalen Textverarbeitung Schritt zu halten. Um diese Abhängigkeit von gelabelten Trainingsdaten zu verringern, werden bei Weak Supervision nicht gelabelte Daten (halb-)automatisch annotiert. Diese Annotationen sind schneller und günstiger zu erhalten. Sie enthalten jedoch auch mehr Fehler. Oft ist eine besondere Behandlung dieser Noisy Labels notwendig, um die Daten erfolgreich nutzen zu können. In dieser Dissertation untersuchen wir die gesamte Weak Supervision Pipeline mit einem Schwerpunkt auf den Einsatz für die Erkennung von Entitäten. Wir entwickeln ein Tool zur automatischen Annotation und präsentieren einen neuen Ansatz zur Modellierung von Noisy Labels. Wir untersuchen die Faktoren, die die Qualität dieses Modells aus theoretischer Sicht beeinflussen, und wir validieren den Ansatz empirisch für verschiedene Aufgaben und Sprachen. Ein wichtiger Aspekt dieser Arbeit ist das Ziel einer realistischen Analyse. Die Untersuchung führen wir unter anderem an mehreren afrikanischen Sprachen durch und zeigen die Leistungsvorteile, die durch Weak Supervision und die Modellierung von Label Noise erreicht werden können. Auch erweitern wir die Analyse auf das Lernen mit wenigen Beispielen. In Bezug auf Klassifizierungsfehler, stellen wir zudem einen neuen Ansatz vor, um interpretierbare Erkenntnisse zu gewinnen

Energy-converting [NiFe] hydrogenases in archaea and bacteria: insights into the energy-transducing mechanism

In recent years a group of multisubunit membrane-bound [NiFe] hydrogenases has been identified in a variety of anaerobic or facultative anaerobic microorganisms. These enzymes share two conserved integral membrane proteins and four conserved hydrophilic proteins with the energy-conserving NADH:quinone oxidoreductases (complex I). Based on experimental evidence derived from physiological and biochemical studies, the various members of this hydrogenase family have been proposed to function as ion pumps being involved in energy-conserving electron transport, reverse electron transport, or both. Therefore these enzymes have been designated energy-converting [NiFe] hydrogenases. In the present work the energy transducing mechanism of energy-converting hydrogenases was studied in comparison to complex I. A particular attention was given to the prosthetic groups involved in the electron transfer pathway, the role of the membrane part and the identification of the coupling ion used by these enzymes. The majority of the experiments were carried out with Ech hydrogenase from Methanosarcina barkeri. The sequence of Ech hydrogenase predicts the binding of three [4Fe-4S] clusters, one by subunit EchC and two by subunit EchF. Previous studies had shown that two of these clusters could be fully reduced under 1 bar of H2 at pH 7 giving rise to two distinct S ½ EPR signals, designated as the g = 1.89 and the g = 1.92 signal. Redox titrations at different pH values demonstrated that these two clusters had a pH-dependent midpoint potential indicating a function in ion pumping. To assign these EPR signals to the subunits of the enzyme a set of M. barkeri mutants was generated in which seven of eight conserved cysteine residues in EchF were individually replaced by serine. EPR spectra recorded from the isolated mutant enzymes revealed a strong reduction or complete loss of the g = 1.92 signal whereas the g =1.89 signal was still detectable as the major EPR signal in five mutant enzymes. It is concluded that the cluster giving rise to the g = 1.89 signal is the proximal cluster located in EchC and that the g = 1.92 signal results from one of the clusters of subunit EchF. The pH-dependent midpoint potential of these two [4Fe-4S] clusters suggests that these clusters simultaneously mediate electron and ion transfer and thus could be an essential part of the ion-translocating machinery. In the two integral membrane subunits of Ech carboxylic residues are found that are highly conserved within the family of energy-converting hydrogenases and complex I. These residues could be part of a transmembrane ion channel. In line with this, Ech hydrogenase activity was inhibited by the carboxyl-modifying reagent N,N’–dicyclohexylcarbodiimide (DCCD). The inhibition of the enzyme correlated quite well with the incorporation of [14C]DCCD in subunits EchA. Using a combination of FT-IR difference spectroscopy and electrochemistry it was shown that the electron transfer reaction catalyzed by Ech hydrogenase from M. barkeri induces a conformational change of the enzyme and the protonation of amino acid side chains. Oxidized minus reduced spectra in the mid infrared range (1800 to 1200 cm-1) revealed conformational changes in the amide I region and a signal at 1720 cm-1 attributed to either an Asp or Glu side chain, protonated in the oxidized state. To identify the coupling ion used by energy converting hydrogenases studies with the enzyme from Carboxydothermus hydrogenoformans were performed. Cell suspensions of C. hydrogenoformans were found to couple the oxidation of CO to CO2 and H2 with the translocation of protons across the membrane at pH 5.9. This transient acidification was inhibited by the protonophore CCCP but was not affected by the sodium ionophore ETH-157, indicating the generation of a primary electrochemical proton gradient. However, no proton translocation coupled to CO oxidation was observed at pH 6.7. On the other hand, at neutral pH, CO oxidation was coupled to sodium ion translocation. This reaction was protonophore insensitive, indicating a primary Na+ translocation. These data indicate that the Coo hydrogenase from C. hydrogenoformans could be a primary sodium pump, which may also use H+ at low pH

How to Involve Young Children in a Photovoice Project: Experiences and Results

For a considerable period of time, discussions on children and how they describe their own life-worlds did not form a part of research practice (CHRISTENSEN & JAMES, 2008). Although some methods are currently being applied with success in research with children, a more comprehensive implementation of different participatory methods is necessary which takes into account the child's peculiarities. One aim of the project "Learning Together, Living Diversity" was to involve children of kindergarten age in participatory research. To demonstrate diversity in a context close to everyday life and to start conversations with the children about this topic we used photographs taken by the children in their living environment. We aim to use the collected findings to develop a didactic method for early childhood education dealing with diversity in the sense of a basic form of existence: every person is unique, and this uniqueness should be perceived as enrichment. In this method, the early childhood phase and the institutional experiences embedded within it are considered fundamental to understand and accept the existence of various life-worlds.Die Auseinandersetzung mit Kindern und der Beschreibung ihrer Lebenswelten aus deren subjektiven Perspektiven war lange Zeit nicht Teil der Forschungspraxis (CHRISTENSEN & JAMES 2008). Obwohl einige Methoden derzeit mit Erfolg in der Forschung mit Kindern angewandt werden, ist eine umfassendere Umsetzung verschiedener partizipativer Methoden notwendig, welche die Besonderheiten des Kindes berücksichtigen. Ein Ziel des Photovoice-Projekts "Gemeinsam lernen, Vielfalt leben" war es, Kinder im Kindergartenalter in die partizipative Forschung einzubeziehen. Hierzu bekamen vier- bis sechsjährige Kinder Digitalkameras zur Verfügung gestellt, mit denen sie jene Dinge festhalten konnten, welche für sie besonders wichtig waren. Die entstandenen Fotos wurden dazu verwendet, die Fülle verschiedener Vorlieben und Existenzformen in einem alltagsnahen Kontext darzustellen und um mit den Kindern über unterschiedliche Arten des Seins ins Gespräch zu kommen. Die Resultate der Studie sollen als Grundlage für die Entwicklung einer didaktischen Methode der frühkindlichen Bildung dienen, wobei das Ziel darin besteht, dass sich bereits junge Kinder mit Vielfalt im Sinne einer Grundform der Existenz altersgerecht auseinandersetzen können: Jeder Mensch ist einzigartig und dies soll als Bereicherung empfunden werden. Dabei werden die frühkindliche Phase und die darin eingebetteten institutionellen Erfahrungen als grundlegend für ein sich entfaltendes Verständnis von Diversität betrachtet

The Strategic Value of Attractive Influencers for Advertising Comunication: The Influence of Parasocial Interaction Processes on the Persuasive Effect of Brand Placements

[EN] Although brand placements can be seen more and more frequently in social media channels of so-called “influencers”, current brand placement research has rarely focused on the persuasive influence of these media characters. The "Balance Model of Product Placement Effects" of Russell and Stern (2006) began to integrate both, the recipient and the recipient's specific perception of the media context, into brand placement research. The result of these considerations is a triadic connection between the recipient, the acting media characters and the placed brands. Adressing this, the following study investigates the mediating influence of cognitive phenomenon of parasocial interactions to an influencer of a YouTube make-up tutorial as well as her specific attitude/valence towards the brands in her immediate context. Brand perception, purchase intention and actual purchase of the presented brand were measured as dependent variables of advertising effectiveness.Gröner, P.; Hedderich, B. (2022). The Strategic Value of Attractive Influencers for Advertising Comunication: The Influence of Parasocial Interaction Processes on the Persuasive Effect of Brand Placements. En Proceedings 3rd International Conference. Business Meets Technology. Editorial Universitat Politècnica de València. 135-144. https://doi.org/10.4995/BMT2021.2021.1361613514