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Roman Concepts of the Literary Persona and Transtextuality. A Study of Bucolic Poetry
No full textThe paper combines an analysis of the distinctive features of the Roman literary persona with two issues discussed in modern character theory: the transtextual identity and the ontological status of literary characters. It focuses on the bucolic poetry by Virgil (1 st century BCE) and Calpurnius Siculus (1 st century CE), as well as on late antique commentaries on Virgil. The bucolic personae can be perceived as characters – which, moreover, can appear as textual artifices or as non-actual individuals – or as masks for text-external persons. In the commentaries, the identification of the mask with the ›man behind the mask‹ is partial and is discussed in terms of single parameters. The ontological status of such a persona is dynamic. It oscillates between that of a character and that of a mask. As a result, the identities of the character and of the author appear to be dynamically modelled, sometimes merging and sometimes separating. These observations have consequences for the question of transtextuality both within the work of one poet and across works. First, the question concerns not only the identity of the personae , but also their ontological status. When homonymous personae are transferred from one text to another, they can retain their ontological status, or change it. When a persona is perceived as a mask, the question of transtextual identity concerns the level of the mask and of the person ›behind the mask‹. Second, the homonymous characters in Virgil’s and Calpurnius’ poetry are intricately connected, sharing some characteristics and not others. From this perspective, a network of partial identifications emerges. If the persona is seen also as a mask for text-external persons, a second level of identifications is introduced into this network, which further complicates it.Peer Reviewe
Streptococcus pyogenes EVs induce the alternative inflammasome via caspase-4/-5 in human monocytes
No full textThe sensing of Gram-negative Extracellular Vesicles (EVs) by the innate immune system has been extensively studied in the past decade. In contrast, recognition of Gram-positive EVs by innate immune cells remains poorly understood. Comparative genome-wide transcriptional analysis in human monocytes uncovered that S . pyogenes EVs induce proinflammatory signatures that are markedly distinct from those of their parental cells. Among the 209 genes exclusively upregulated by EVs, caspase-5 prompted us to study inflammasome signaling pathways in depth. We show that lipoteichoic acid (LTA), a structural component of Gram-positive bacterial membranes present on EVs from S. pyogenes and other Gram-positive species, is sensed by TLR2 which triggers the alternative inflammasome composed of NLRP3 and the inflammatory caspases-4/-5 to mount an IL-1β response without inducing cell death. For S. pyogenes , we identify TLR8 as a sensor to mediate caspase-4/-5-dependent IL-1β secretion. Notably, inflammasome activation by intact bacteria is independent of the global virulence regulator CovS in monocytes. Overall, our study highlights a new role for TLR2 and caspase-4/-5 in the recognition of Gram-positive EVs in human monocytes.The recognition of Gram-positive EVs by innate immune cells remains poorly understood. This study identifies alternative inflammasome activation by S. pyogenes and Gram-positive EVs in human monocytes and highlights a new role for TLR2 and caspase-4/-5 in this process. Lipoteichoic acid (LTA) as a constituent of Gram-positive EVs activates the alternative inflammasome via TLR2. IL-1β secretion is regulated by MYD88, RIPK1, CASP8, and CASP4/5. EVs promote monocyte survival by inhibiting caspase-3 activation.Deutsche Forschungsgemeinschaft (DFG)http://dx.doi.org/10.13039/501100001659Louis-Jeantet Foundation (Fondation Louis-Jeantet)http://dx.doi.org/10.13039/501100001706Max Planck SocietyTang Prize FoundationPeer Reviewe
Mining for Justice: Marginalized Voices and the Quest for Sustainability in the Colombian Amazon
No full textNach 60 Jahren Konflikt erlebt das kolumbianische Amazonasgebiet einen raschen Wandel, geprägt von Entwaldung durch Rohstoffindustrie, v.a. durch den Goldabbau, den Aufständische und Kriminelle ausnutzen. Marginalisierte Gruppen wie Indigene und Frauen sind besonders betroffen. Umweltbewegungen und indigene Aktivisten arbeiten an Lösungen, wobei viele indigene und afro-stämmige Gemeinschaften den Goldabbau in ihren Gebieten erhalten möchten. Diese Doktorarbeit untersucht das Potenzial des Goldabbaus aus der Sicht marginalisierter Gruppen, insbesondere People of Color, und fragt 1) nach der Bedeutung von Nachhaltigkeit im Goldabbau und seine Auswirkungen auf den Naturschutz, 2) nach nachhaltigen sozial-ökologischen Transformationen in intersektionalen Kontexten und 3) nach gerechten Zukunftsvisionen lokale Women of Color. Die Untersuchung sozial-ökologischer Transformationen erfolgte mithilfe von Umweltgerechtigkeit, Intersektionalität und Dekolonialität, unter Einsatz von Dokumentenanalysen, teilnehmender Beobachtung, halbstrukturierten Interviews und Szenarienentwicklung. Die Datenerhebung umfasste drei Forschungsreisen nach Kolumbien (März 2022 -November 2023) über insgesamt zehn Monate – sieben davon in Putumayo. Marginalisierte Gruppen wie Kleinbergleute und indigene Gemeinschaften fordern Veränderungen, die Ungleichheiten bekämpfen, aber über eine Kostenverteilung hinausgehen. Sie betonen lokale Vorstellungen von gutem Leben und stellen die Annahme infrage, dass unternehmerischer Bergbau der einzige Weg zur Nachhaltigkeit sei. Sozial-ökologische Transformationen entstehen, wenn unterdrückerische Systeme, die Ungleichheit und Umweltschäden befördern, konfrontiert werden und Verfahrensgerechtigkeit sowie Anerkennung angestrebt werden. Gemeinsam mit Frauen vor Ort untersuchte ich die emotionalen Aspekte der Transformation und ihrer Kosten anhand von drei Zukunftsvisionen.After 60 years of conflict, the Colombian Amazon faces rapid transformation. It has experienced significant deforestation due to extractive industries, particularly gold mining, which is exploited by insurgents and criminals, adversely affecting marginalized groups like Indigenous people and women. Conversely, environmental movements and Indigenous activists are working to avert the crisis, with many Indigenous and Afro-descendant groups striving to protect the critical role of gold mining in their communities. This PhD thesis explores how to ensure this transition by examining the potential of Colombian Amazon gold mining through the lens of marginalized groups, particularly people of color. I investigate 1) the meaning of sustainability in gold mining and its conservation implications, 2) sustainable social-ecological transformations amid intersectional differences, and 3) how local women of color envision equitable futures for the region. I explored social-ecological transformations through insights from environmental justice, intersectionality, and decoloniality, using document analysis, participatory observation, semi-structured interviews, and scenario-building exercises in investigative ethnography. Data collection included three trips to Colombia from March 2022 to November 2023, totaling ten months—seven in Putumayo. Marginalized groups, such as artisanal miners and Indigenous communities, demand changes that address inequity beyond cost distribution. This underscores the value of local views on good living and contests the belief that corporate mining is the sole route to sustainability. I conclude that social-ecological transformations for sustainability stem from these groups confronting oppressive systems that fuel social inequity and environmental damage, striving for procedural equity and recognition. Engaging with local women, I explored the emotional aspects of transformation and its costs through three visions of the future
Austrian Physics Teachers’ Views on Language and Inclusive Content Learning in Multilingual Classrooms
No full textThe Austrian education system faces the ongoing challenge of addressing linguistic diversity in classrooms where many middle school students speak a first language other than German. Yet, teaching practices often prioritize subject content over inclusion through language-sensitive approaches, limiting equitable access to education. In response, the revised Austrian middle school curriculum emphasizes “language learning and reading” as a cross-cutting theme, promoting language-sensitive teaching across all subjects, including physics. This study explores how Austrian middle school physics teachers ( N = 131) perceive and implement language-sensitive practices in response to the new curriculum. Using a questionnaire, it investigates their attitudes towards (1) the revised curriculum, (2) reading, and (3) the role of language in physics lessons. Findings show that while teachers are highly motivated to implement the curriculum, they often lack the methodological knowledge necessary to effectively support learners with lower German language proficiency. Physics instruction poses specific challenges due to its reliance on subject-specific terminology and academic discourse, further disadvantaging students with lower German language skills. This research highlights the urgent need for targeted professional development to support inclusive, language-sensitive teaching, ensuring all students—regardless of linguistic background—can access and succeed in physics education.Funded and supported by funds from the Austrian Federal Ministry of Education, Science and Research and the Innovation Foundation for Education in Austria and the APC was funded by the University of Graz.Austrian Federal Ministry of Education, Science and Research and the Innovation Foundation for Education in AustriaUniversity of GrazPeer Reviewe
Mechanistic Promiscuity in Cobalt‐Mediated CO2 Reduction Reaction: One‐ Versus Two‐Electron Reduction Process
No full textWe compare the carbon dioxide reduction (CO2RR) activity and selectivity of the complexes [(Hbbpya)CoII]2+ and [(Mebbpya)CoII]2+, which contain two 2,2′‐bipyridine chelating groups linked by ‐NH or ‐NCH3 moieties, respectively. Whereas [(Hbbpya)CoII]2+ forms CO under electrocatalytic conditions in presence of phenol (PhOH) with high selectivity, [(Mebbpya)CoII]2+ shows higher hydrogen evolution reaction activity and low selectivity for CO production. The molecular origin of the difference in product selectivity was analysed based on spectroscopic trapping of reactive intermediates and detailed kinetic and theoretical studies. A difference in mechanism is evident; whereas an efficient proton relay mediated by the ‐NH group initiates a two‐electron reduction of CO2 in the case of [(Hbbpya)CoII]2+, one‐electron chemistry prevails for [(Mebbpya)CoII]2+. Under stopped‐flow conditions, we trapped the one‐electron reduced CO2 radical anion in [(Mebbpya)CoI(CO2−•)], which forms oxalate under aprotic conditions. This study underlines the importance of subtle electronic and protonation changes in controlling the CO2RR product selectivity.Deutsche Forschungsgemeinschaft 10.13039/501100001659DFG Center of ExcellencePeer Reviewe
Maximal strength training improves muscle-tendon properties and increases tendon matrix remodulation in well-trained triathletes
No full textThis study assessed the effects of a 12-week strength training (ST) intervention on Achilles and patellar tendon stiffness and tendon-matrix blood-borne markers in well-trained triathletes performing concomitant high-volume aerobic training. Eighteen triathletes (VO2max: 64.43 ± 4.65 ml kg−1 min−1) were randomized into a combined endurance and ST group (3-times/week; intervention) or endurance-only group (control). Pre- and post-intervention assessments included ultrasound-based force-elongation measurements of the Achilles and patellar tendons, blood analysis of selected markers before and after an experimental ST session in weeks 1 and 12, and dynamic strength and endurance testing. Achilles (39.1 ± 31.8%) and patellar tendon stiffness (15.8 ± 8.5%), isometric maximal knee extensor strength (8.9 ± 5.7%), and squat one-repetition maximum (20.0 ± 9.7%) significantly increased in the intervention group (all p ≤ 0.002). Additionally, serum concentrations of matrix metalloproteinase (MMP) I (46.30 ± 20%; p = 0.027) and decorin (30.50 ± 19.94%; p = 0.015) increased after the first experimental ST session, while after the second session MMP-III (40.77 ± 20.13%; p = 0.040) and decorin (36.59 ± 37.81%; p = 0.007) were increased. Baseline tenascin-c concentrations decreased significantly only in the control group (-19.49 ± 20.55%; p = 0.029). Our data clearly show improved muscle-tendon properties of the plantar flexor muscles and quadriceps femoris, indicating Achilles and patellar tendon stiffness to be similarly responsive to heavy ST despite concomitantly performing high volumes of endurance training.Open Access funding enabled and organized by Projekt DEAL.Technische Universität Chemnitz (3137)Peer Reviewe
Total Generalized Variation with Finite Elements for Imaging and Shape Optimization
No full textDiese Arbeit beschäftigt sich mit variationellen Methoden für inverse Probleme, die mittels totaler Variation (TV) und totaler generalisierter Variation (TGV) regularisiert werden. Die meisten bestehenden Modelle und Implementierungen von TGV nutzen diskretisierungen auf kartesischen Gittern, sodass die Anwendbarkeit auf allgemeinere Geometrien stark einschränkt ist. Der erste Beitrag dieser Arbeit ist eine Formulierung der TGV für stückweise konstante Finite-Elemente-Funktionen auf triangulierten Gittern. In der ursprünglichen Form reduziert sich TGV in diesem Fall auf TV und bietet daher keinen Vorteil. Die entwickelte Formulierung überträgt das TGV-Konzept gezielt auf stückweise konstanter Finiter Elemente, wodurch der staircasing effect verhindert wird. Ein weiterer Teil dieser Arbeit behandelt geometrische inverse Probleme, bei denen die diskrete totale Variation des Normalenvektorfeldes einer triangulierten Oberfläche als Regularisierung dient. Im Mittelpunkt steht hier unter anderem ein numerisches Verfahren, das auf der alternating direction method of multipliers (ADMM) basiert, sowie eine diskrete Variante des Shape Calculus, mit dem Zweck die entstehenden nicht-glatten Optimierungsprobleme effizient zu lösen. Der dritte Beitrag dieser Arbeit erweitert die zuvor vorgestellte TGV für stückweise konstante Daten auf den Normalenvektorfelder triangulierter Gitter in 3D. Da Normalenvektoren auf der Einheitssphäre liegen – einer Mannigfaltigkeit und keinem euklidischen Raum – ist eine spezielle Behandlung notwendig. Hierzu wird eine neuartige Formulierung der diskreten totalen generalisierten Variation vorgeschlagen, die auf einem maßgeschneiderten Finite-Elemente-Raum basiert, der geeignet ist eine diskretisierung des pushforward-Operators des Normalenvektors darzustellen.This thesis focuses on variational methods for inverse problems regularized with total variation (TV) and total generalized variation (TGV). Most existing TGV models and implementations are designed for Cartesian grids, which limits their applicability in more general settings. The first contribution of this thesis is a formulation of TGV for piecewise constant finite element functions. With the original formulation, TGV degenerates to TV when applied to piecewise constant functions, providing no benefit. Through this thesis, a discrete formulation of total generalized variation for piecewise constant finite element functions on triangulated meshes is proposed. This formulation leverages the idea of TGV for this setting without degenerating to TV. This is demonstrated in numerical experiments. The next part of this thesis deals with geometric inverse problems that are regularized by the discrete total variation of the normal vector field of a triangulated surface. The focus lies particularly on the derivation of a numerical algorithm based on an alternating direction method of multipliers (ADMM) to solve the resulting non-smooth optimization problems efficiently. This requires the solution of a smooth shape optimization problem as a sub-problem. Therefore, shape optimization calculus, in particular in the context of triangulated meshes is presented. As a part of this thesis, the second-order analytic shape derivative formulas are generalized to manifolds of arbitrary dimension and co-dimensions. Finally, extends the concept of TGV to the normal vector field of a finite element mesh in 3D. Since normal vectors lie on the sphere, which is a nonlinear manifold rather than in Euclidean space, a dedicated treatment is necessary. The novel formulation of the discrete total generalized variation of the normal vector is based on a custom finite element space that can be used to represent a discrete analogue of the pushforward operator of the normal vector
Deep Learning for Sequential Data
No full textDeep Learning (DL) ist ein Teilgebiet des maschinellen Lernens (ML), das auf neuronalen Netzen basiert, die auf verschiedenen Abstraktionsebenen lernen und dabei traditionelle ML Methoden in einer Vielzahl von Aufgaben häufig übertreffen. Diese Dissertation untersucht verschiedene Geschäftsaufgaben mit sequenziellen Daten und analysiert die DL Eignung. Zuerst stellen wir den DL Begriff und die Taxonomie der sequenziellen Datenforschung vor. Die ermittelte Taxonomie zeigt die Dimensionen auf, entlang derer unsere Analyse von DL für die sequenzielle Datenforschung durchgeführt wird. Kapitel 2 untersucht die Machbarkeit und Eignung der automatischen Inhaltsüberwachung und deren Erklärbarkeit. Wir konsolidieren die Arbeiten zur Erkennung antisozialen Verhaltens und identifizieren DL- sowie nicht-DL-basierter Algorithmuskandidaten und betonen die Bedeutung der Interpretierbarkeit. Kapitel 3 widmet sich der jüngsten Popularität von Smart Contracts (SC), Softwareprogrammen, die auf einer Blockchain basieren und bestimmte Aktionen ausführen können. Wir befassen uns mit den rechtlichen, rechnerischen und statistischen Aspekten von SCs und untersuchen, ob reale Anwendungen mit den vorgeschlagenen Medienanwendungsfällen korrelieren und potenziell die Wirtschaft revolutionieren können. DL-Methoden dienen als Instrument zum Verständnis des SCs-Ökosystems. Kapitel 4 stellt das Code-Zusammenfassungs (CZ) ‚Algorithm Choice Framework‘ für den Wissenschaftsbereich vor, das Wissenschaftler bei der Entwicklung ihres CZ-Systems unterstützt. Die Anwendung des Frameworks wird anschließend am Anwendungsfall von Quantlet.com veranschaulicht. Abschließend untersucht Kapitel 5 die Überwachung der CZ-Systeme. Das Kapitel schlägt das Meta-Learning-Modul vor, das die Überwachung, Modellauswahl und Ensemblebildung von CZ-Modellen mithilfe einer Mischung von Experten ermöglicht. Abschließend wird erörtert, wie das Modul eine prädiktive Perspektive auf die Interpretierbarkeit bieten kann.Deep Learning (DL) is a subset of machine learning (ML) based on neural networks that learn at different abstraction levels, frequently outperforming traditional ML methods in a variety of tasks. This dissertation investigates various business tasks involving sequential data and analyzes the DL methods suitability. First, we introduce the notion of deep learning and the taxonomy of sequential data research. The identified taxonomy showcases the dimensions along which our holistic analysis of DL for sequential data research is conducted. The second chapter investigates the feasibility and suitability of automatic content monitoring and the explainability of such systems. Here, we consolidate the work on antisocial behavior detection and identify algorithm candidates, including DL and non-DL-based methodologies, and highlight the importance of the interpretability. The third chapter is dedicated to the recent popularity of Smart Contracts (SC), the software programs that live on a blockchain and can perform specific actions. Here, we dive into the legal, computational, and statistical aspects of SCs, identifying whether real-world applications correlate with the suggested media use cases and can potentially revolutionize the economy. DL methods serve as a supporting tool for understanding the SCs ecosystem. The fourth chapter proposes the code summarization Algorithm Choice Framework for the science domain, supporting scientists in designing their code summarization system. The framework’s usage is then exemplified in the real-world use case of Quantlet.com. Finally, chapter 5 investigates monitoring the code summarization systems. The chapter proposes the Meta-Learning Module that enables code summarization model monitoring, model selection, and ensembling using a mixture of experts. Finally, it discusses how the module can give a predictive perspective on interpretability
Kigoma-Ujiji, a Global History of a Liminal Town since the Mid-Nineteenth Century
No full textThe publication of this work was supported by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Drawing on a wide range of archives, historical publications, oral history, graphic, audiovisual and web sources, Geert Castryck presents Kigoma-Ujiji as both shaping and being shaped by global transformations. On the surface, the book offers almost two centuries of urban history on Lake Tanganyika in western Tanzania, close to the Burundian and Congolese borders, in a place that has been a transport hub throughout that time. Beneath the surface, it is also about major transformations on a global scale, and about people dealing with and coping with these global challenges far from the supposed global powerhouses. Urbanization and infrastructure, colonization and decolonization, liberalization and democratization, war refugees, world heritage and translocal identities are the entry points for interpreting transformations that are local and global at the same time. The author uses the analytical categories of "liminal space" and "portal of globalization" to link the marginality and uncertainty that characterize the successive transformations in Kigoma-Ujiji with the urban resilience and creativity used to manage these transformations
Electrophysiological resting-state signatures link polygenic scores to general intelligence
No full textIntelligence is associated with important life outcomes. Behavioral, genetic, structural, and functional brain correlates of intelligence have been studied for decades, but questions remain as to how genetics are related to trait expression and what intermediary role brain properties play. This study investigated these mediations in a representative sample of 434 individuals, comprising young and older adults. Polygenic scores (PGS) for intelligence were calculated. Resting-state EEG recordings were analyzed using graph theory quantifying functional connectivity across different frequencies. We tested whether global and local graph metrics like efficiency and clustering mediated the association between PGS and intelligence. PGS significantly predicted variance in intelligence and were related to frequency-specific graph metrics in areas predominantly located in parieto-frontal regions, which in turn were associated with intelligence. These findings, based on the first study linking PGS to intelligence using EEG-derived graph metrics, identify candidate pathways through which genetic variation may shape intelligence, providing a foundation for future hypothesis-driven investigations. Data for this study were collected as part of the Dortmund Vital Study ( https://www.researchprotocols.org/2022/3/e32352 ; ClinicalTrials.gov: NCT05155397).Open Access funding enabled and organized by Projekt DEAL.Leibniz-Institut für Arbeitsforschung (IfADo) (3465)Peer Reviewe