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Untersuchung des Effektes der telefonisch angeleiteten Reanimation (T-CPR) auf das Überleben und auf das neurologische Ergebnis von extrahospital reanimationspflichtigen Patienten bei verlängerter Hilfsfrist
Full text linkUntersucht wurde, welchen Einfluss die telefonisch Reanimation (T-CPR) auf Endpunkte des extrahospitalen Kreislaufstillstandes (OHCA) hat. Dies umfasst die Durchführung einer Laienreanimation, die Wiederherstellung eines Spontankreislaufes, die Krankenhaus-Einlieferung, das Überleben sowie das neurologische Outcome bei Entlassung des Patienten aus dem Krankenhaus. Auch andere Aspekte, wie der Ort des Notfalls oder das Einhalten der gesetzlichen Hilfsfrist wurden in ihrer Auswirkung auf die Endpunkte untersucht. Für die Untersuchung wurden Notarztprotokolle der Jahre 2012 bis 2015 des Einzugsgebietes der Leitstelle Nord gesichtet, relevante Daten herausgesucht sowie die eingeschlossenen Patienten im Krankenhaus nachverfolgt. Dort wurde der klinische Verlauf und insbesondere das neurologische Outcome anhand der Arztbriefe recherchiert. Es zeigte sich, dass durch die T-CPR signifikant mehr Laienreanimationen stattfanden, sowie signifikant mehr defibrillierbare Rhythmen als Initialrhythmus detektiert wurden. Tendenziell wurden eine höhere Anzahl an Spontankreisläufen festgestellt, kein Unterschied konnte beim Überleben und neurologischem Outcome gezeigt werden. Dass für die Hauptfragestellung keine Signifikanz nachzuweisen war, ist unerwartet. Mögliche Gründe könnten die fehlende Beatmung (Sauerstoffdepletion), sowie die verlängerte Zeit bis zum Beginn der Herzdruckmassage sein. Durch Telefon-Reanimation als Methode allein können Verbesserungen hinsichtlich des Überlebens und neurologischen Ergebnisses nach OHCA nicht erreicht werden. Um das Outcome des Kreislaufstillstands nachhaltig zu verbessern, bedarf es offenbar eines Maßnahmen-Bundles, um alle Elemente der sogenannten Chain of survival zu verbessern. Eine generelle Empfehlung der T-CPR ohne Atemspende ist durch die vorliegende Studie nur unzureichend gestützt
Beeinträchtigung der hippocampalen Musterseparation und weiterer Kognitionsdomänen bei Patient*innen mit Multipler Sklerose
Full text linkKognitive Defizite und insbesondere Gedächtnisstörungen sind bei Patient*innen mit Multipler Sklerose weit verbreitet. Ein relevanter Teilaspekt des episodischen Gedächtnisses stellt die Musterseparation dar. Sie bezeichnet die Fähigkeit Repräsentationen von sich überlappenden Ereignissen unabhängig voneinander zu enkodieren und konsolidieren. Die Hippocampusregionen des Gyrus Dentatus sowie CA3 gelten als Hauptvermittlungsstrukturen für diesen Prozess. Zur Untersuchung der hippocampalen Musterseparation wurden im Rahmen der vorliegenden Arbeit MS-Patient*innen und neurologische gesunde Kontrollproband*innen einer kognitiven Testung unterzogen. Die Musterseparation wurde mithilfe des Mnemonic Similaritiy Task (MST) getestet. Zusätzlich wurden neuropsychologische Tests sowie Fragebögen bearbeitet. Von den Patient*innen wurde mittels Hirn-MRT-Aufnahmen die Gedächtnisleistung in Bezug auf das Gesamthirnvolumen und das zerebrale Läsionsvolumen untersucht. Die MS-Patient*innen erreichten in allen Gedächtnisaufgaben signifikant schwächere Leistungen als die Kontrollpersonen. Insbesondere die Musterseparation zeigte sich signifikant beeinträchtigt. Eine Verschlechterung der Musterseparationsfähigkeit konnte mit zunehmendem Läsionsvolumen sowie abnehmendem Hirnvolumen festgestellt werden. In dieser Studie kann gezeigt werden, dass die hippocampale Musterseparation sowie weitere Kognitionsdomänen bei der MS-Erkrankung Defizite aufweisen. Zusammenfassend wird die These unterstützt, dass Schädigungen des Hippocampus, insbesondere Funktionsstörungen im Gyrus Dentatus sowie im Areal CA3, im Rahmen der Erkrankung auftreten und wesentliche Gedächtnisfunktionsstörungen bedingen können
Association of Corticosteroid Inhaler Type with Saliva Microbiome in Moderate-to-Severe Pediatric Asthma
Full text linkBackground/Objectives: Metered-dose inhalers (MDIs) and dry powder inhalers (DPIs) are common inhaled corticosteroid (ICS) inhaler devices. The difference in formulation and administration technique of these devices may influence oral cavity microbiota composition. We aimed to compare the saliva microbiome in children with moderate-to-severe asthma using ICS via MDIs versus DPIs. Meth.: Saliva samples collected from 143 children (6-17 yrs) with moderate-to-severe asthma across four European countries (The Netherlands, Germany, Spain, and Slovenia) as part of the SysPharmPediA cohort were subjected to 16S rRNA sequencing. The microbiome was compared using global diversity (α and β) between two groups of participants based on inhaler devices (MDI (n = 77) and DPI (n = 65)), and differential abundance was compared using the Analysis of Compositions of Microbiomes with the Bias Correction (ANCOM-BC) method. Results: No significant difference was observed in α-diversity between the two groups. However, β-diversity analysis revealed significant differences between groups using both Bray-Curtis and weighted UniFrac methods (adjusted p-value = 0.015 and 0.044, respectively). Significant differential abundance between groups, with higher relative abundance in the MDI group compared to the DPI group, was detected at the family level [Carnobacteriaceae (adjusted p = 0.033)] and at the genus level [Granulicatella (adjusted p = 0.021) and Aggregatibacter (adjusted p = 0.011)]. Conclusions: Types of ICS devices are associated with different saliva microbiome compositions in moderate-to-severe pediatric asthma. The causal relation between inhaler types and changes in saliva microbiota composition needs to be further evaluated, as well as whether this leads to different potential adverse effects in terms of occurrence and level of severity
Essays on Development and International Economics
Full text linkThis doctoral thesis investigates the determinants of growth of firms and regions in developing countries. While there is a plethora of economic tools that can be used to stimulate economic development, this thesis focuses on the role of place-based policies and service inputs as drivers of innovation activities of firms. The first two chapters examine the effects of Special Economic Zones (SEZs), a prevalent industrial policy aimed at fostering local development, on the performance of firms and household well-being in developing countries. Chapter 1 evaluates the effects of SEZ establishment on firm productivity growth in India using a novel geo-referenced dataset and a difference-in-differences design with inverse probability weighting. Findings show no overall productivity gains from SEZs, but heterogeneous effects emerge: firms in privately-owned SEZs benefit, while those in publicly-owned ones show losses, potentially due to rent-seeking behavior among managers. Chapter 2 shifts focus to household welfare in Africa, analyzing SEZs' effects on wealth using geocoded Demographic and Health Survey data from ten countries (1990–2020). Results indicate that households living within 10 km of SEZs experience significant increases in wealth. Positive effects include improved access to utilities, better housing quality, and higher consumption of durable goods, alongside a shift away from agricultural employment. This suggests that SEZs bring with them urbanisation trends. Chapter 3 explores how the liberalization of upstream services sector affects innovation in downstream Indian manufacturing firms. Using a shift-share research design, I show that service liberalization increases the product scope of manufacturing firms. The mechanism analysis reveals that allowing Foreign Direct Investments into the banking sector relaxes firm’s financial constraints and facilitates product innovation
The moderating role of extraversion in the relationship between trait mindfulness and pain adaptation
Full text linkIntroduction Pain habituation, the reduction in response to repeated painful stimuli, is a positive adaptation process, while pain sensitization is linked to chronic pain. Traits like mindfulness and extraversion affect pain processing, but their influence on pain adaptation and potential interactions remains underexplored. This study aimed to examine the relationship between trait mindfulness, extraversion, and pain adaptation, assessing their predictive value and any interaction effects. Materials and method Fifty-two healthy participants, mean age = 23.29 ± 2.052 years, completed questionnaires measuring trait mindfulness and extraversion, followed by an experimental pain stimulation to assess pain adaptation. Correlation analysis and hierarchical regression analysis were used to explore the relationships between traits and pain adaptation, and potential interaction effects. Result Trait mindfulness positively correlated with extraversion, but neither trait showed a significant correlation with pain adaptation. In addition, neither trait mindfulness nor extraversion significantly predicted pain adaptation. However, a significant interaction was found between the two traits, suggesting that extraversion moderates the relationship between trait mindfulness and pain adaptation. Conclusion Trait mindfulness and extraversion are interrelated traits whose interaction affects pain habituation and the extent to which individuals with higher levels of trait mindfulness exhibit greater pain adaptation appears to depend on their levels of extraversion. These findings suggest that trait mindfulness and extraversion may act as protective factors in chronic pain development. Mindfulness-based interventions may be particularly effective for individuals with specific personality traits. This can inform further research to explore these implications for pain management
Chemocatalytic Conversion of Dinitrogen to Ammonia Mediated by a Tungsten Complex
Full text linkWhereas molybdenum dinitrogen complexes have played a major role as catalytic model systems of nitrogenase, corresponding tungsten complexes were in most cases found to be catalytically inactive. Herein, we present a modified pentadentate tetrapodal (pentaPod) phosphine ligand in which two dimethylphosphine groups of the pentaPodMe (P5Me) ligand have been replaced with phospholanes (Pln). The derived molybdenum complex [Mo(N2)P5Pln] generates 22 and the analogous tungsten complex [W(N2)P5Pln] 7 equivalents of NH3 from N2 in the presence of 180 equivalents of SmI2(THF)2/H2O, rendering the latter the first tungsten complex chemocatalytically converting N2 to NH3. In contrast, the tungsten complex [W(N2)P5Me] generates ammonia from N2 only in a slightly overstoichiometric fashion. The reasons for these reactivity differences are investigated with the help of spectroscopic and electrochemical methods
BH3·SMe2 addition enables molar mass control via chain stabilization in phosphine–borane dehydropolymerization
Full text linkWe report the synthesis of high molar mass polyphosphinoboranes using commercially available reagents through thermal dehydropolymerization in the presence of Lewis acids and bases. These dehydropolymerizations produce materials of higher molecular weight compared to the state-of-the-art catalyst, Cp(CO)2FeOTf ([PhPH-BH2]n (2), 5 mol% LiOTf, 2 M in 2-MeTHF, 100 °C, 24 h; Mn = 80 000 g mol−1, Đ = 1.64 cf. 5 mol% Cp(CO)2FeOTf, 2 M in toluene, 100 °C, 24 h, Mn = 40 000 g mol−1, Đ = 1.64). We propose a mechanism for the thermal dehydropolymerization of PhPH2·BH3 (1) with additives. Initially, the phosphine–borane adduct dissociates, yielding borane in situ, which acts as a (pre)catalyst for the dehydrogenation of 1. Subsequent addition polymerization occurs as described previously, but the addition of Lewis acids and Lewis bases allows for reversible complexation of both termini. Competition between temporary chain capping and termination events results in fewer termination events over time, leading to high molar mass materials. With this mechanism in mind, we were able to show that added BH3·SMe2 allows for control over the molar mass of the resulting materials. These results show that transition-metal catalysts are not needed in the thermal dehydropolymerization of PhPH2·BH3, and offer a new mechanistic insight that may unlock greater control over the dehydropolymerization of main-group substrates
Multifrequency seafloor acoustic backscatter as a tool for improved biological and geological assessments – updating knowledge, prospects, and challenges
Full text linkMultibeam echosounders (MBES) have emerged as a primary tool for seafloor mapping over the past three decades. Technological advancements and improved data processing methods have increased the accuracy and spatial resolution of bathymetric measurements, and have also led to the increasing use of MBES backscatter data for seafloor geological and benthic habitat mapping applications. MBES backscatter is now frequently used to characterize habitat for marine flora and fauna, contribute to the development of effective marine spatial planning and management strategies, and generally better classify the seabed. Recently, further technological advances have enabled the acquisition and analysis of backscatter at multiple sonar operating frequencies (multifrequency backscatter), with follow-on potential benefits for improved seafloor characterization and classification. This review focuses on the currently available peer-reviewed papers related to multifrequency seafloor acoustic backscatter, providing a comprehensive summary of the contributions across different benthic environments, setting the stage for related applications and outlining challenges and research directions
The spatiotemporal evolution of a giant submarine canyon system – the Agadir Canyon
Full text linkSubmarine canyon systems are gateways for sediment transport from the shelf to the deep sea. They are the primary conduit for gravity flows that move substantial amounts of carbon, nutrients, and pollutants from the continental shelves to the deep sea. Despite their importance, it often remains unclear how these canyons initiate, and which factors determine their evolution from initiation to mature stage. The Agadir Canyon, located at the Northwest African Continental Margin, represents one of the largest canyon systems worldwide and a conduit for some of the largest turbidity currents on Earth. However, our understanding currently rests on legacy DSDP drilling and poorly resolved seismic imaging of turbidites beyond the canyon mouth. Here, we present multichannel seismic data from proximal and distal reaches of the Agadir Canyon combined with age constraints from the DSDP borehole. This allows us to detail its morphological and temporal evolution from inception to present-day. The Agadir Canyon initiated during the Middle Miocene on top of a preceding wide and shallow channel-levee-system. The Middle to Late Miocene saw the canyon continue eroding and narrowing into its present morphology. The evolution of the canyon was primarily driven by climate perturbations, sea level fluctuations and regional tectonic uplift of the Moroccan hinterland. These factors increased sandy sediment supply to the shelf edge, which promoted powerful erosive turbidity currents. However, most of the canyon fill is slope-derived mud-rich mass transport deposits, which healed the canyon morphology over geologic timescales. Regional salt diapirism, the development of the Canary Islands and the onset of bottom currents during the Miocene actively re-routed sediments and actively shaped its morphology
Klimarelevanz und Naturschutzwert der Moore in Schleswig-Holstein unter aktuellen und historischen Gesichtspunkten
Full text linkMoore sind in den vergangenen Jahren immer weiter ins Zentrum des Klima- und Naturschutzes gerückt. Sie sind Quellen von Treibhausgasemissionen und ihre Biodiversität hat dramatisch abgenommen. Um diese Trends aufzuhalten, unterschiedliche Ziele zur Wiederherstellung von Moorökosystemen ausgesprochen. Schleswig-Holstein gilt als moorreiches Bundesland. Aktuell existieren jedoch nur unzureichende Informationen über die THG-Emissionen sowie den naturschutzfachlichen Wert dieser Ökosysteme. Mit diesem Thema befasst sich die vorliegende, aus vier Studien bestehende Dissertation: (I): In der ersten Studie werden die THG-Emissionen der Moore Schleswig-Holsteins mit der GEST-Methode erfasst und Reduktionsmöglichkeiten unterschiedlicher Vernässungsszenarios berechnet. (II): In der zweiten Studie wird die Kulisse der echten Moore um die kohlenstoffreichen Böden erweitert, außerdem wird in dieser Studie zusätzlich der naturschutzfachliche Wert der botanischen Artenvielfalt (NBV, Klassen 1-4) beurteilt. (III): In der dritten Studie wurde der aktuelle Zustand der Moore (I/II) mit dem historischen Zustand in den 1930er Jahren anhand von topographischen Karten (Messtischblätter 1:25.000) verglichen. (IV): In dieser Studie werden Kohlenstoffverlusttraten, Sackungsraten sowie Veränderungen des Bodenprofils für landwirtschaftlich genutzte Hochmoore in einer Projektregion erfasst. Die Studien zeigen, dass der aktuelle Zustand der Moore in Schleswig-Holstein sowohl im Hinblick auf die THG-Emissionen wie auch des NBV als schlecht oder sehr schlecht einzustufen ist. Durch die Verknüpfung von THG-Emissionen mit Naturschutzaspekten können differenzierte Handlungsschwerpunkte aufgezeigt werden