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Investigating evolutionary and developmental cellular trajectories with single-cell phylotranscriptomics
Get PDFMulticellular organisms achieve their complexity through a rich diversity of cell types, each performing specialized roles within the organism. As the fundamental units of form and function, cell types offer a compelling vantage point for investigating how developmental processes intersect with evolutionary history. The gene expression programs that define each cell type encode not only their functional identities but also carry molecular signatures of evolutionary constraint and innovation. For a long time, efforts to dissect these programs were limited by the resolution of traditional bulk transcriptomic approaches. The advent of single-cell transcriptomics now enables these programs to be examined at cellular resolution, allowing the study of cell type gene expression patterns across both developmental and evolutionary timescales. This breakthrough opens the possibility to address longstanding questions in evolutionary developmental biology (evo-devo), such as how novel cell types emerge and how ontogeny relates to phylogeny. Among multicellular lineages, vertebrates stand out for their remarkable morphological complexity and extensive cellular diversity, making them ideal for exploring these evo-devo questions. In this thesis, I design a single-cell phylotranscriptomic approach that combines single-cell transcriptomics with gene evolutionary origins to uncover molecular evolutionary signatures embedded within cell type-specific gene expression programs. By applying this strategy, I elucidate mechanisms of cell type evolution, including how the recruitment of taxonomically restricted genes (TRGs) contributes to novel cell type identity, and reveal the cellular basis of the molecular hourglass pattern in vertebrate development. Overall, this work advances our understanding of the interplay between evolution and development at the level of cellular gene expression
In memoriam Prof. Dr. Werner Grote (1938–2025)
Get PDFNachruf auf Werner Grote, ehemaliger Professor und Leiter des Instituts für Humangenetik an der Medizinischen Fakultät der CAU.Obituary for Werner Grote, former professor and head of the Institute of Human Genetics at the Medical Faculty of Kiel University
In memoriam Prof. Dr. Arnold Oberschelp (1932–2024)
Get PDFNachruf auf Arnold Oberschelp, ehemaliger Professor für Logik und Wissenschaftslehre an der Mathematisch-Naturwissenschaftlichen Fakultät der CAU.Obituary for Arnold Oberschelp, former professor of logic and philosophy of science at the Faculty of Mathematics and Natural Sciences at Kiel University
Tumor budding and lymphovascular invasion as prognostic factors in p16-positive oropharyngeal squamous cell carcinomas
Get PDFBackground We aimed to validate the prognostic significance of tumor budding (TB) in p16-positive oropharyngeal squamous cell carcinomas (OPSCC). Methods We analyzed digitized H&E-stained slides from a multicenter cohort of five large university centers consisting of n = 275 cases of p16-positive OPSCC. We evaluated TB along with other histological parameters (morphology, tumor-stroma-ratio, lymphovascular invasion (LVI), perineural invasion) and calculated survival outcomes using both univariate and multivariate analyses. Results TB was identified as an independent prognostic parameter, with TB-high cases showing inferior outcomes in univariate (HR: 3.08, 95%-CI: 1.71-5.54) and multivariate analyses (HR: 4.03, 95%-CI: 1.65-9.83). Similarly, LVI remained an independent prognostic factor (HR: 3.00, 95%-CI: 1.22-7.38). A combined classification including TB and LVI stratified cases into low-, intermediate- and high-risk categories. We could not detect correlations between TB and the number of lymph node metastases or between TB and an extracapsular extension of lymph node metastases. Conclusions In addition to LVI, we could identify TB as an independent prognostic factor in p16-positive OPSCC in this multicenter study cohort. Thus, evaluating TB along with LVI in a combined scheme for prognostication might help to establish a more personalized treatment regimen for patients with p16-positive OPSCC
Intersektionalität in der germanistischen Literatur- und Mediendidaktik: Ansätze, Forschungsdesiderate und Potenziale
Get PDFAls Forschungsgegenstand und Analyseperspektive findet Intersektionalität seit einigen Jahren Eingang in die germanistische Literatur- und Medienwissenschaft sowie -didaktik. Die didaktisch orientierten Ansätze zum unterrichtlichen Umgang mit ›Intersektionalität‹ sowohl auf Ebene der Texte und Medien als auch der Lernenden und Lehrenden sind jedoch noch wenig aufeinander bezogen und der Begriff wird in der Disziplin oft vage und immer wieder auch synonym zu den Begriffen ›Diversität‹ und ›Heterogenität‹ genutzt. Ziel des Beitrags ist es in einem ersten Schritt, das bis dato noch wenig ausdifferenzierte Forschungsfeld innerhalb der germanistischen Literatur- und Mediendidaktik zu systematisieren und Forschungsdesiderate zu benennen. Exemplarisch an einer Jugendfernsehserie als Bildungsgegenstand des Deutschunterrichts und Lernprodukten einer Deutschklasse, die sich im Rahmen ihres Literaturunterrichts mit der Fernsehserie befasst hat, werden in einem zweiten Schritt sowohl Potenziale als auch didaktische Wege eines intersektional ausgerichteten Literaturunterrichts im Fach Deutsch aufgezeigt.For some years now, intersectionality has also found its way into German literature and media studies and didactics as a subject of research and an analytical perspective. However, the didactically orientated approaches to dealing with intersectionality in the classroom in regard to texts and media and in relation to learners and teachers, are still little interrelated and the term ›Intersectionality‹ is often used vaguely and repeatedly deployed as a synonym for the terms ›diversity‹ and ›heterogeneity‹ in the discipline. The aim of this article is, as a first step, to systematise the hitherto undifferentiated field of research within German literature and media didactics and to identify research desiderata. In a second step, it is shown the potential and didactic paths of intersectionally orientated literature lessons, based on a youth television series as an educational object of German lessons and learning products of a German class that has dealt with the television series as part of its literature lessons
Connecting sea to market: Using network analysis to understand social–ecological dynamics in seafood value chains in Pisco, Southern Peru
Get PDFSmall-scale fisheries represent complex human-nature interactions, targeting different species in different locations throughout the year. On land, fishers are at the core of diverse seafood value chains that serve local and distant markets. Understanding interconnectivity and the value chain dynamics of these complex systems is key to designing meaningful resource management plans that are adaptive to changes. To examine these adaptive interactions in the value chain network, we used the empirical case study of a small-scale fishery in San Andrés, Peru. Data comes from semi-structured surveys (n = 58) with fishers and buyers, along with historical and contextual data from qualitative interviews and literature review. We visualize and analyse our data as social–ecological network interactions, which indicate patterns of adaptive behaviour among fishers with different catch and market strategies. Resilience and adaptive capacity are observed among fishers that have multiple options along the value chain. A fisher is thus more resilient to climatic and seasonal change if they fish for multiple species across different seasons. [...] Findings suggest that fishers and buyers do exhibit adaptive capacity in different identifiable ways, which we interpret and explain as four adaptive fisher archetypes. This allowed us to define a theoretical fisher motif aimed at generalizing the structural configuration of a typical fisher who has adaptive capacity. This motif can be used as a social–ecological network model to test adaptive capacity in other fisheries. We discuss and argue that recognizing and supporting diverse value chains is key for adaptive capacity to future environmental and social changes and that fishers play a central role as agents with adaptive decision-making capacity to potentially improve overall system resilience
Elevated Tropical Sea Surface Temperatures During the Globally Warm Miocene Caused Heat Stress for Caribbean Coral Reefs
Get PDFThe warm Miocene (23.0–5.3 Ma) is considered a model case for the global climate of the near future. In view of the current coral reef crisis, studies on Miocene reefs can contribute to predictions regarding the stress resilience of today's reefs against global warming. A Late Miocene (6.2–5.5 Ma) reef coral fauna from Hispaniola Island (Caribbean) characterised by ecologically tolerant taxa was originally interpreted to reflect cool-eutrophic waters. However, the associated planktonic foraminifer assemblage and new TEX86H–based temperature reconstructions document an oligotrophic shallow-water environment harbouring 30–31°C. Thus, in conjunction with unusually low vertical growth rates and erratic trace element signatures of massive reef corals, the coral fauna documents critically high temperatures and a response to heat stress rather than cool upwelling. The findings demonstrate the relevance of understanding shallow-water ecosystems from past warm periods for developing scenarios of a future, warmer world
Uncertainties as a Guide for Global Water Model Advancement
Get PDFGlobal water models allow us to explore the terrestrial water cycle in earth-sized digital laboratories to support science and guide policy. However, these models are still subject to considerable but also reducible uncertainties that can be attributed to mainly three sources: (1) imbalances in data quality and availability across geographical regions and between hydrologic variables, (2) poorly quantified human influence on the water cycle, and (3) difficulties in tailoring process representations to regionally diverse hydrologic systems. New, more accurate, and larger datasets, as well as better accumulated and even enhanced process knowledge, will help to reduce these uncertainties and thus improve model consistency with our perceptions and accuracy given existing observations. This review examines the sources of uncertainty crucial for global water models and proposes actions to mitigate them, thereby providing a roadmap for model advancement. Following this path will yield more consistent and accurate models that are urgently needed to tackle key scientific and societal challenges
Fast‐Charging Lithium–Sulfur Batteries
Get PDFThe growing demand for sustainable energy solutions has intensified research into lithium-sulfur batteries (LSBs) due to their potential for high energy density, though their commercialization is primarily hindered by challenges in achieving satisfactory cycle stability and energy density, with fast-charging capabilities also requiring significant improvement. This review explores strategies to enhance the fast-charging capabilities of LSBs, addressing critical issues such as lithium polysulfide (LiPSs) shuttling, sluggish reaction kinetics, and lithium dendrite formation. The review discusses the mechanisms of fast-charging, followed by a comprehensive analysis of key techniques and the crucial role of various battery components that can revolutionize fast-charging capabilities. It covers challenges related to electrical and ionic conductivity, optimizing Li-ion mobility, immobilizing LiPS, designing suitable electrolytes, integrating catalysts to accelerate LiPSs conversion, and engineering cathodes and separator modifications. Additionally, the review discusses scaling challenges for fast-charging LSBs, including electrolyte design, sulfur loading, polysulfide shuttle mitigation, and electrode stability. The review concludes by providing future perspectives on developing next-generation LSBs that could transform the energy storage landscape, with a sustainable, high-capacity, and rapid-charging alternative to current battery technologies, with significant implications for electric vehicles and portable electronics
Maßnahmen zur Verkürzung der Liegezeiten von Patienten nach minimal-invasivem Aortenklappenersatz (TAVI)
Get PDFDiese Dissertation beschäftigt sich mit der Frage, ob durch standardisierte Maßnahmen („Fast-Track“-Konzept) am Universitätsklinikum Kiel die Liegezeit für transfemorale TAVI-Patienten verkürzt werden kann. Primäre Endpunkte der Studie waren die Entlassung nach erfolgreicher TAVI-Prozedur sowie die 30-Tages-Mortalität. Dazu wurden 333 Patienten in eine Kontrollgruppe (n = 227) vor Einführung dieser standardisierten Maßnahmen und eine Fallgruppe (n = 106) nach deren Einführung eingeschlossen. Ebenfalls wurden Subgruppen anhand der präprozeduralen Planung (elektiv versus nicht-elektiv) gebildet, um zu zeigen, dass die peri- und intraprozeduralen Maßnahmen zu einer deutlichen Reduktion der Aufenthaltsdauer beim elektiven Patienten beitragen können. Im Vergleich der Mediane der Liegezeiten für den Gesamtaufenthalt sowie für die Zeit bis zur Entlassung der Patienten nach durchgeführter Prozedur zeigte sich ein signifikanter Unterschied zu Gunsten der neu eingeführten Maßnahmen. So waren bei beiden Gruppen sowie Subgruppen die Liegezeiten der Fallgruppe stets kürzer als die der Kontrollgruppe. Hieraus kann geschlossen werden, dass die eingeführten Maßnahmen des Universitätsklinikums Kiel Wirkung gezeigt haben und das Erreichen von maximal drei Tagen Gesamtaufenthalt für alle elektiven transfemoralen TAVI-Patienten ein realistisches Ziel der kommenden Jahre sein kann. Ebenso konnte gezeigt werden, dass durch die „Fast-Track“-Maßnahmen die Patientensicherheit, gemessen an der 30-Tages-Mortalität, nicht gesunken ist, sondern die Zahl der Todesfälle nach 30 Tagen in der Fallgruppe verringert werden konnte