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Omitting transesophageal echocardiography before catheter ablation of atrial fibrillation
Full text linkOne devastating but potentially avoidable complication of catheter ablation of atrial fibrillation is thromboembolic stroke. It could be caused by mobilization of the left atrial appendage thrombus. Transesophageal echocardiography is the gold standard for preprocedural screening. However, concerns have been raised regarding the necessity of performing TEE before every PVI. We aimed to evaluate the safety of an individualised risk-based approach to transesophageal echocardiography with respect to thromboembolic cerebrovascular events in patients undergoing catheter ablation for atrial fibrillation. We performed a retrospective clinical study. A total of 1155 patients undergone catheter ablation for atrial fibrillation were enrolled. Prior to the procedure, patients were scheduled for transesophageal echocardiography only if they had a history of thromboembolic stroke, left atrial appendage thrombus, or inappropriate anticoagulation regimen in the previous three to four weeks. The incidence of periprocedural cerebrovascular thromboembolic events was assessed. A total of 4 out of 1153 (0.35%) patients, who underwent the ablation procedure, experienced thromboembolic cerebrovascular events. The rate of cerebrovascular thromboembolic events in our study doesn't exceed that reported in most multicentre trials. In all four patients with cerebrovascular thromboembolic events, imaging after the event showed the absence of thrombus in the left atrial appendage. The low event rates limited statistical analysis of possible risk factors for cerebrovascular thromboembolic events. In summary, an individualized selective approach to transesophageal echocardiography before catheter ablation of atrial fibrillation proved to be safe. In patients with uninterrupted oral anticoagulation and no history of thromboembolic events, transesophageal echocardiography before the catheter ablation could be omitted
К вопросу о функциях русского несовершенного вида в лирическом тексте
Full text linkDer Beitrag analysiert die verschiedenen Funktionen der russischen Imperfektformen im poetischen Text. Die Untersuchung erfolgt im Rahmen der linguistischen Poetik und konzentriert sich auf die grammatikalischen Mittel zur Schaffung der künstlerischen Welt in der russischen Poesie des letzten Drittels des 20. - frühen 21. Jahrhunderts. Die analysierten Kontexte stammen aus den Werken von O. G. Chukhontsev, O. A. Yuriev, Y. P. Moritz, V. A. Sosnora und M. N. Eisenberg. Die Autorin identifiziert die Bedingungen für die Verwirklichung verschiedener besonderer Bedeutungen der Imperfektform in einem poetischen Text, postuliert das Potenzial der untersuchten Verbformen im Bereich der Schaffung von Chronotop- und Handlungselementen in der Lyrik und zeigt eine besondere Darstellungsfunktion auf, die mit der Erweiterung der zeitlichen Perspektive der künstlerischen Welt des Gedichts verbunden ist und das lyrische Subjekt mit den Eigenschaften eines »allwissenden« Erzählers ausstattet.This article analyses the various functions of the Russian imperfect tense in the poetic text. The study is conducted within the framework of linguistic poetics and focuses on the grammatical means of creating the artistic world in Russian poetry of the last third of the 20th - early 21st century. The contexts analysed are taken from the works of O. G. Chukhontsev, O. A. Yuriev, Y. P. Moritz, V. A. Sosnora and M. N. Eisenberg. The author identifies the conditions for the realisation of various special meanings of the imperfect tense in a poetic text, postulates the potential of the studied verb forms in the field of creating chronotope and plot elements in poetry, and demonstrates a special representational function associated with the expansion of the temporal perspective of the artistic world of the poem, endowing the lyrical subject with the characteristics of an »omniscient« narrator.В статье анализируются различные функции форм русского несовершенного вида в поэтическом тексте. Исследование выполнено в русле лингвистической поэтики, и в центре внимания находятся грамматические средства создания художественного мира в русской поэзии последней трети XX в. – начала XXI в. Анализируемые контексты извлечены из произведений О. Г. Чухонцева, О. А. Юрьева, Ю. П. Мориц, В. А. Сосноры и М. Н. Айзенберга. Выделяются условия реализации различных частновидовых значений несовершенного вида в поэтическом тексте, постулируется потенциал исследуемых глагольных форм в области создания элементов хронотопа и сюжета в лирике, а также выявляется особая изобразительная функция, связанная с расширением временной перспективы художественного мира стихотворения и наделением лирического субъекта чертами «всезнающего» повествователя
POEMA 3.2025
Full text linkPOEMA ist ein komparatistisch angelegtes Jahrbuch, das sich der systematischen Erforschung von Lyrik und Gedicht widmet. Es richtet sich an Fachwissenschaftlerinnen und Fachwissenschaftler aller Philologien wie auch der mit anderen Kunstformen befassten Wissenschaften und der philosophischen Ästhetik. Das dritte Heft bringt insbesondere die frankophone und germanophone Lyrikforschung zusammen und versammelt Beiträge zu verschiedenen Konzepten der Lyrik bzw. der poésie lyrique, von Martin Opitz bis zur Virtual Poetry des 21. Jahrhunderts.POEMA is a comparative yearbook dedicated to the systematic study of lyric poetry and poems. It is aimed at scholars in all fields of philology as well as their fields of research concerned with different art forms and philosophical aesthetics. The third issue notably brings together French and German scholarship on poetry, presenting contributions that explore diverse conceptions of lyricism or poésie lyrique, spanning from Martin Opitz to virtual poetry in the 21st century.POEMA est une revue annuelle comparatiste consacrée à l’étude systématique de la poésie et du poème. Elle s’adresse aux spécialistes de toutes les philologies ainsi qu’à leurs domaines de recherche liés aux différentes formes d’art et à l’esthétique philosophique. Le troisième numéro rassemble des recherches francophones et germanophones sur la poésie lyrique et propose des contributions sur différents concepts de la poésie ou de la poésie lyrique, de Martin Opitz à la poésie virtuelle du XXIe siècle
Essays on Sustaianble Finance
Full text linkThis cumulative dissertation examines the role of Sustainability-Linked Bonds (SLBs) in financial markets, focusing on their pricing, the stock market reaction to their issuance, and their potential to hedge climate risk. Across three empirical papers, the thesis applies advanced econometric methods to provide novel insights into sustainable finance. The first paper investigates the yield differential between SLBs and conventional bonds in the primary market, using Nelson–Siegel–Svensson yield curve fitting and a synthetic matching approach to isolate the “sustainability premium.” Fixed effects panel regressions reveal that SLBs often price at a yield discount, influenced by bond, issuer, and ESG-related characteristics. The second paper conducts an event study on SLB issuance announcements, estimating abnormal returns with the market model. Positive and significant short-term cumulative abnormal returns suggest that SLB issuance signals sustainability commitment to investors. The study also discusses price pressure as an alternative explanation. The third paper explores the connectedness between climate risk indicators (physical and transition risk) and ESG/conventional assets using Diebold–Yilmaz spillover measures, Quantile VAR, Quantile-on-Quantile Connectedness, and DCC-GARCH models. It evaluates the hedging effectiveness of ESG assets under climate risk, finding that sustainable bonds moderately hedge transition risk but offer limited protection against physical risk. Overall, the thesis contributes to the literature by combining innovative modeling techniques with a focus on SLBs and climate risk, offering both academic and practical implications for sustainable finance, portfolio management, and climate risk mitigation
The Perfect Storm?: A communication lobbying perspective on management and design of the EU Common Fisheries Policy
Full text linkNatural resource pool management problems are still not resolved globally. Various calls for transformational change are prevalent and crosscutting across various areas such as climate, food security, health and biodiversity. This dissertation contributes to the literature on the mechanisms and processes that hinder the development of efficient and effective policies, using the European Union Common Fisheries Policy (CFP) as a case study. Through social network analysis, the role of informational lobbying, its interaction with formal institutions and legislative rules using non-cooperative legislative bargaining models were explored. Communicational lobbying impact on policy learning through policy belief updating, as well as knowledge aggregation processes were measured . We also simulated scenarios of how different factors can shape fisheries opportunities decisions by the EU AGRIFISH Council of ministers. Our findings reveal that informational lobbying network of the CFP plays a role in policy belief updating processes preferences, intensifying belief biases and limiting adaptive policy learning. Additionally, stakeholders predominantly rely on their initial beliefs, suggesting that future studies should explore belief formation mechanisms, as well as path dependency and institutional inertia to better understand why some actors rely more on observational learning than are receptive to communicational learning. Scientific uncertainties may exasperate these belief biases when insufficient measures to address potential errors are put in place. Ecosystem Based Fisheries Management , context-specific harvest control rules, as well as improved communication network structures and additional governance mechanisms have been highlighted as potential solutions. Future research could integrate bio-economical and meta-modeling, and further unravel mechanisms driving belief biases and improve effective policy learning
Insights on the role of alkaline magmatic systems for epithermal gold potentials: a case study of Conical Seamount, Papua New Guinea
No full textAlkaline porphyry-epithermal systems represent main gold sources throughout the world. The Tabar-Lihir-Tanga-Feni (TLTF) island chain in north-eastern Papua New Guinea exhibits a particular metal endowment, especially exemplified by the giant Ladolam gold deposit on-shore Lihir island with more than 47.1 Mt Measured and Indicated Resources. In the past decades, increased attention has been given to the seamounts off-shore Lihir. Conical Seamount, located south to Lihir, has been well documented because of the hosting gold-mineralization, which is the site where epithermal-style mineralization was discovered on the seafloor first. However, the magmatic system of Conical Seamount underlying such a prominent gold mineralization has not been well constrained and remained widely unknown. This work identifies and describes the main stages of magmatic evolution underneath Conical Seamount along with their importance for the metal transport and deposition. In a broader context, this study addresses the strong link between alkaline magmas and epithermal mineralization. A detailed petrographic study combined with geochemical measurements of different magmatic samples recovered during several cruises conducted with the research vessel SONNE (SO94, SO133, SO166 and SO299) was carried out. Conical Seamount is characterized by several key features for the metal enrichment, transport and deposition: subduction-modified mantle source, significant fractional crystallization, shallow magma chamber marked by metal extraction through sulfide precipitation and fluid exsolution. However, magmatic rejuvenation through the ascent of a new, more hydrous parental magma appears to be an additional necessary stage prior to epithermal mineralization
Design und Synthese von Carbazolomaleimiden und Morphogenen Naturstoff-inspirierten Verbindungen als neuartige BMP-Stimulatoren
No full textPluripotent stem cells can differentiate into virtually any cell type of the human body, making them a valuable tool in regenerative medicine and drug discovery. However, achieving targeted differentiation requires a profound understanding of the biology that guides cell fate decisions. In this context, chemical probes serve as valuable tools for investigating and modulating growth factor-mediated signaling. In a stem cell-based, phenotypic screen probing Bone Morphogenetic Protein (BMP)-dependent aspects during early embryogenesis and osteogenesis, indoyl maleimides and the natural product-inspired derivative IM1 were identified as potential BMP stimulators. Optimization of the indoyl maleimide cluster yielded carbazolomaleimide 2b with enhanced osteogenic potency. Mechanistic studies revealed that 2b induces an osteogenic morphology by targeting noncanonical BMP signaling, in part via GSK3β inhibition. When combined with canonical BMP potentiators, 2b synergistically amplified BMP-dependent osteogenic outputs, highlighting the potential of dual-targeting strategies. Thus, 2b serves as a new and promising tool for modulating noncanonical BMP signaling. Following the structure elucidation of IM1, a diastereospecific, 8-step diversity-oriented synthesis was established, yielding 25 novel IM1 derivatives. This SAR collection enabled the identification of crucial structural, conformational, and stereochemical features essential for BMP activity. Optical resolution of the most active diastereomers yielded four enantiomers with highly stereospecific BMP activity. Both active and inactive enantiomers serve as a high-quality chemical probe set for target deconvolution and represent a significant expansion of the molecular BMP toolbox, advancing our understanding of BMP signaling in health and disease
Evaluation of the fracture resistance of posterior monolithic CAD/CAM crowns restoring custom-made implant abutments after artificial aging
Full text linkThis study was carried out to investigate the effect of using different commercially available CAD/CAM materials for fabrication of molar crowns on the fracture strength of custom-made abutments after dynamic loading and thermal cycling. A total of 88 identical custom-made CAD/CAM abutments milled out of titanium, zirconia, lithium disilicate and ceramic-reinforced polyetheretherketone were divided into 11 test groups (n=8) and restored with CAD/CAM crowns milled out of zirconia, lithium disilicate, and ceramic-reinforced polyetheretherketone. Lithium disilicate abutments were restored only with lithium disilicate and ceramic-reinforced polyetheretherketone crowns. Specimens were artificially aged in a chewing simulator for 1.2 million cycles of dynamic loading with simultaneous thermal cycling. The surviving specimens were loaded to fracture in the universal testing machine. The data were tested for normality using the Shapiro-Wilk test and for homogeneity of variance using the Levene test revealing heterogeneity and deviation from the normal distribution. Statistical significance was tested for using Welch’s Analysis of variance with post-hoc Games-Howell test (95% confidence interval). In total, 81 specimens survived the artificial aging process simulating five years of clinical service. The fracture modes and means of the fracture strength varied between the groups, zirconia abutments restored with zirconia crowns had the highest mean with 5529.5 N and lithium disilicate abutments restored with ceramic-reinforced polyetheretherketone crowns had the lowest mean with 1582.5 N. Although the tested combinations showed different fracture values and modes, all the groups that survived the artificial aging and fractured above 900 N are considered safe from a mechanical point of view for restoring single implants in the posterior region within normal loading conditions
Stabilized Finite Elements for Resource Modeling and Optimization
Full text linkThis thesis is concerned with the application of systems of partial differential equations (PDEs) to investigate various real-world problems encountered in the fields of geophysics, fish biomass sustainability, and suspension-sedimentation processes
Die Prävalenz von Genduplikation und Nichtfunktionalisierung in der Plasmidevolution
Full text linkThis thesis investigates the prevalence of gene duplications and non-functionalization in plasmid genome evolution. It provides a comprehensive analysis of plasmid pseudogenes and their association to the loss of plasmid self-transmissibility, which represents as a possible route to domesticated plasmids as exemmplified in enterobacterial isolates. Furthermore, the thesis introduces SegMantX, a novel tool for detecting diverged segmental duplications and demonstrates its ability to detect DNA transfer and plasmid hybridization events. Overall, the thesis highlights that gene non-functionalization and amplification in plasmids is frequently due to mobile genetic elements such as transposons and insertion sequences