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Simulator training in focus assessed transthoracic echocardiography (FATE) for undergraduate medical students : results from the FateSim randomized controlled trial
No full textIntroduction
Ultrasound is important in heart diagnostics, yet implementing effective cardiac ultrasound requires training. While current strategies incorporate digital learning and ultrasound simulators, the effectiveness of these simulators for learning remains uncertain. This study evaluates the effectiveness of simulator-based versus human-based training in Focused Assessed with Transthoracic Echocardiography (FATE).
Materials and methods
This single-centre, prospective, randomised controlled study was conducted during an extracurricular FATE workshop (approximately 420 min) for third-year medical students. Participants were randomly assigned to the study group (training solely on simulators) or the control group (training on human subjects). Both groups completed a theory test and a self-assessment questionnaire before the course (T1) and at the end of the training (T2). At T2, all participants also completed two Direct Observation of Procedural Skills (DOPS) tests—one on the simulator (DOPSSim) and one on humans (DOPSHuman).
Results
Data from 128 participants were analysed (n = 63 study group; n = 65 control group). Both groups exhibited increased competency between the T1 and T2 self-assessments and theory tests (p < 0.01). In the DOPSHuman assessment at T2, the control group performed significantly better (p < 0.001) than the study group. While motivation remained consistently high among both groups, the study group rated their “personal overall learning experience” and the “realistic nature of the training” significantly worse than the control group (p < 0.0001). Both groups supported the use of ultrasound simulators as a “supplement to human training” (study: 1.6 ± 1.1 vs. control: 1.7 ± 1.2; p = 0.38), but not as a “replacement for human training” (study: 5.0 ± 2.3 vs. control: 5.4 ± 2.1; p = 0.37).
Conclusion
Both simulator- and human-based training effectively developed theoretical and practical skills in FATE. However, the simulator group demonstrated significantly poorer performance when applying their skills to human subjects, indicating limitations in the transferability of this simulator-based training to real-life patient care. These limitations of simulator-based ultrasound training should be considered in future training concepts
Märchenerzählen in der Gegenwart : ethnografische Annäherungen an eine mündliche Praxis unter dem Eindruck der Coronapandemie
No full textIm Fokus der Studie stehen Selbstentwürfe von Märchenerzähler:innen in Deutschland. Hierzu wurde dieser Personenkreis nach seinen Beweggründen für das öffentliche Erzählen befragt sowie dessen Performanz untersucht. Die Datenaufnahme fiel – unvorhersehbar – in die Zeit der Coronapandemie. Da es während dieser Phase zu weitreichenden und einschneidenden Veränderungen im Alltag kam, musste die ursprüngliche Konzeption der Arbeit wesentlich verändert werden. Als Konsequenz hieraus entstanden Zeitzeugnisse einer historischen Krisensituation unserer Gesellschaft. Gleichzeitig enthält die Studie einen umfassenden gegenwartsorientierten Beitrag zur Erzähler:innenforschung. Dabei baut sie auf das Erzählerlexikon von Kathrin Pöge-Alder sowie die Werke von Johannes Merkel und Siegfried Neumann auf.
Die Materialgrundlage für diese Arbeit lieferten in der Hauptsache qualitative Interviews mit 13 Personen, die vor und während der Coronapandemie befragt wurden. Altersmäßig verteilen sich die ausgewählten Gesprächspartner:innen auf die Geburtsjahrgänge von 1943 bis 1966. Befragt wurden nur Erzähler:innen, die ihre Tätigkeit als Dienstleistung anboten. Ergänzend kam es bei dieser Studie auch zu teilnehmenden Beobachtungen auf analogen und digitalen Erzählveranstaltungen. Bei der Auswertung des erhobenen Materials wurde u.a. auf die von Albrecht Lehmann entwickelte Methode der Bewusstseinsanalyse Bezug genommen, um die Aussagen der Befragten im Zusammenhang mit ihrer Biografie und der Erzählsituation weiterführend analysieren zu können.
Nach den Aussagen der interviewten Forschungspartner:innen hatten sie ihre ersten Berührungspunkte mit dem Erzählen in der Kindheit. Märchenerzählen stellt bis heute keinen staatlich anerkannten Ausbildungsberuf dar. Daher gelangten die Befragten nach Anregungen in der Kindheit auf Umwegen zu ihrer Profession. In der Regel sahen sie ihre Tätigkeit als Folge einer Berufung. Auslöser waren etwa Schicksalsschläge, Sinnkrisen oder der Wunsch nach künstlerischer Selbstverwirklichung. Diejenigen, die ausschließlich mit dem Erzählen ihren Lebensunterhalt zu bestreiten versuchten, sprachen von harten Arbeitsbedingungen, die ein hohes Maß an Kreativität von ihnen verlangten. Die Rede war von unterschiedlichen Erzählkonzepten, die zum Beispiel bei Kinderveranstaltungen, im Tourismusbereich, in Gesundheits- und Pflegeeinrichtungen, in Wirtschaftsunternehmen oder auf einer Baustelle zur Anwendung kamen. Mit dem Ausbruch der Coronapandemie, bei der zeitweise öffentliche Veranstaltungen untersagt waren, spitzte sich die wirtschaftliche Situation der Befragten erheblich zu. Einige von ihnen entwickelten digitale Alternativangebote und stießen dabei auf neue technische Herausforderungen. Zudem waren die Fragen des Einkommens nicht befriedigend zu klären oder das Gefühl entstand, im digitalen Raum die persönliche Authentizität nicht vermitteln zu können.The study focuses on the self-conceptions of storytellers in Germany. To this end, this group of people were asked about their motivations for public storytelling and their performance was examined. The data collection took place – unpredictably – during the COVID-19 pandemic. Since there were far-reaching and drastic changes in everyday life during this phase, the original concept of this study had to be changed significantly. As a result, contemporary testimonies of a historical crisis situation in our society were created. At the same time, the study contains a comprehensive contemporary contribution to research on oral storytellers. It builds on the „Erzählerlexikon“ by Kathrin Pöge-Alder and the works of Johannes Merkel and Siegfried Neumann.
The material basis for this work was mainly provided by qualitative interviews with 13 people who were interviewed before and during the COVID-19 pandemic. The selected interviewees were born between 1943 and 1966. Only storytellers who offered their work as a service were interviewed. In addition, this study also included participant observations at analog and digital storytelling events. When evaluating the research data, reference was made to the method of „Bewusstseinsanalyse“ developed by Albrecht Lehmann, among others, in order to be able to further analyze the statements of the interviewees in connection with their biography and the narrative situation.
According to the research partners interviewed, they had their first contact with telling of fairy tales as children. To this day, storytelling is not an officially job. Therefore, the interviewees arrived at their profession in a roundabout way after being inspired in childhood. As a rule, they saw their activity as the result of a calling. Triggers included strokes of fate, crises of meaning or the desire for artistic self-realization. Those who tried to make a living exclusively from storytelling spoke of hard working conditions that demanded a high degree of creativity from them. There was talk of very different narrative concepts that were used, for example, at children's events, in the tourism sector, in health and care facilities, in commercial enterprises or on a construction site. With the outbreak of the COVID-19 pandemic, during which public events were temporarily banned, the economic situation of the interviewees came to a head. Some of them developed digital alternatives and encountered new technical challenges in the process. In addition, the questions of financial income could not be satisfactorily clarified or the feeling arose that personal authenticity could not be conveyed in the digital space.298 Seiten ; Illustratione
Medieval overexploitation of peat triggered large-scale drowning and permanent land loss in coastal North Frisia (Wadden Sea region, Germany)
No full textElectrochemistry as a sustainable tool for the synthesis of heterocycles with a N,O-Moiety
Get PDF119, 763 Seiten ; Illustrationen, Diagramm
Cuticular hydrocarbons and collective response to water stress in a desert ant
No full text1. With the accelerating pace of climate change, we urgently need to understand how physiological traits shape behavioural plasticity in response to environmental stress. In social insects, collective behaviour operates without central control but through interactions among individual participants. In the aggregate, this produces a collective response to environmental conditions.
2. Here we consider how variation among desert ant colonies in the cuticular hydrocarbons (CHCs) that prevent water loss is associated with variation among colonies in the collective behaviour that manages water stress. Colonies of the desert ant, Pogonomyrmex barbatus, differ in the collective regulation of foraging activity to manage water loss to evaporation while foraging. Foraging is regulated through olfactory interactions between outgoing and returning foragers, which determine a forager's decision whether to leave the nest on the next trip. Some colonies are risk-averse, with foragers less likely to make foraging trips in dry conditions, while others are risk-tolerant, with foragers who do not reduce foraging trips in dry conditions.
3. We found that behavioural differences among colonies are associated with the capacity of their foragers' CHCs to prevent water loss. In risk-averse colonies whose foragers make fewer trips in dry conditions, the abundance of alkenes was significantly higher. High abundance of alkenes, with a low melting point, makes the CHC layer more permeable, increasing susceptibility to water loss. In one of 2 years of this study, we found that workers in risk-averse colonies also had significantly shorter n-alkanes, which further enhance water permeability of the CHC layer and thus desiccation risk.
4. To our knowledge, this is the first report of variation among conspecific colonies in CHC profile that is linked to colony differences in collective behaviour
Joseph Anton Koch und Johann Michael Wittmer : Camposantiner in Ninfa und Olevano Romano
No full textDer Beitrag widerlegt aus interdisziplinärer Perspektive die gängige These, die Ruinenstadt Ninfa sei erst seit den 1920er Jahren wahrgenommen worden. Er entstand im Rahmen eines vom Autor initiierten internationalen und interdisziplinären Forschungsprojekts zur Geschichte der Garten- und Ruinenlandschaft, das kunsthistorische, kulturwissenschaftliche und raumgeschichtliche Ansätze verbindet und die Entdeckung sowie künstlerische Aneignung Ninfas im langen 19. Jahrhundert untersucht. Im Zentrum der Ausführungen steht die Entdeckungsgeschichte vor allem in der ersten Hälfte des 19. Jahrhunderts durch die mit dem Campo Santo Teutonico in Rom eng verbundenen Künstler Joseph Anton Koch – zentrale Figur unter den deutschsprachigen Künstlern am Tiber – und seinen Schwiegersohn Johann Michael Wittmer. Zusammen mit Künstlern von Rang wie August Kopisch und Ludwig Richter wurden in der deutsch-internationalen Künstlerkolonie Olevano Romano und in Ninfa vor allem seit den 1820er Jahren neue Motive und Räume im südöstlichen Latium erschlossen. Auf Basis von Skizzenbüchern, Reiseberichten, architekturhistorischen Beobachtungen und lokalhistorischen Quellen zeigt die Studie, wie Reisende und Künstler – nicht zuletzt aus dem englischsprachigen Raum – Ninfa und die Region zwischen Genazzano, Sermoneta und Circeo zum mythisch-romantischen Sehnsuchtsort stilisierten. Analysiert werden Ruinenästhetik sowie die Rezeption mittelalterlicher Architektur im Kontext transnationaler Netzwerke; hervorgehoben wird die Bedeutung der Skizzenbücher als bislang wenig erforschter Quellentyp für künstlerische Aneignungsprozesse und motivische Übertragungen
Machine learning for the elucidation of multiphase processes and systems
No full textAtmospheric chemistry governs many processes in the context of air quality, climate, and human health. It includes, among others, multiphase interactions between gases and condensed phases, affecting the formation, transformation and removal of atmospheric constituents. Understanding multiphase chemistry is therefore essential for accurately describing atmospheric composition and its impacts. In this context, atmospheric aerosols play a particularly important role. They serve as cloud nuclei, transport reactive species, provide reaction surface and impact radiative forcing, the key driver of global warming. Among them, organic aerosols represent an abundant fraction, yet their formation and transformation remains poorly understood, largely contributing to uncertainty in climate and health modelling. The immense diversity of precursor compounds for organic aerosols, coupled with complex environmental conditions and multiphase chemistry, pose a major challenge for laboratory and modelling studies alike. At the same time, advances in measurement and monitoring technologies generate large volumes of atmospheric data. Data-centric methods like machine learning pose a powerful opportunity to use these data to forward the understanding of atmospheric processes and improve parameterizations of Earth system models. This study explores and advances machine learning applications in multiphase chemistry, including compound property prediction, model acceleration, uncertainty quantification, experiment design, and multiscale modelling. The focal points of this thesis can be summarized as follows:
- Advancement of quantitative structure-activity relationship (QSAR) models with novel artificial neural network architectures. This includes the application of pattern-detecting convolutional neural networks on one-hot encoded simplified molecular input line entry system (SMILES) representations of molecular structures to estimate the reduction potentials of atmospherically-relevant quinones. Reduction potentials determine the quinones' reactivity, and therefore their ability to undergo redox-cycling, which leads to the catalytic production of reactive oxygen species (ROS). ROS are likely associated with adverse health effects of air pollution, as they react with biomolecules in the lungs of exposed humans. Trained convolutional neural network models permit the rapid screening of atmospherically-relevant quninones that pose an elevated risk of adverse health effects, without the need of expensive measurements. Another advancement of QSAR methods is the application of graph convolutional neural networks alongside graph representations of molecules to estimate their saturation vapor pressure. Vapor pressures determine the partitioning equilibrium of atmospheric compounds between the condensed and gas phase. Their accurate determination is of high relevance in various fields of atmospheric science, critically affecting the formation and growth of secondary organic aerosol, which account for a substantial mass fraction of tropospheric aerosols. A novel group contribution-assisted, adaptive-depth graph convolutional neural network architecture outperforms existing methods for vapor pressure prediction, even when trained on relatively few experimental data.
- Acceleration of kinetic multilayer process models for mass transport and chemical reactions in aerosols through machine learning surrogate models. While differential equation models are capable of accurately simulating the growth and aging of atmospheric aerosols, their computational expense often poses restrictions on their application in inverse or global atmospheric modelling. Artificial neural network and polynomial chaos expansion surrogate models can be trained on sampling data from differential equation models to reproduce their output. The trained surrogate models show high accuracy in comparison with their reference models, and offer immense acceleration by multiple orders of magnitude. They were successfully used to aid complex differential equation models in inverse modelling tasks, notably reducing the computational cost.
- Development of the Numerical Compass, a computational method for automated uncertainty quantification of process models and experiment design. The Numerical Compass utilizes a fit ensemble, i.e., an ensemble of plausible model solutions consistent with experimental data, to identify combinations of laboratory parameters for experiments that lead to near-optimal model constraints. This enables researchers to use a more target-oriented approach when designing experiments by addressing the major sources of uncertainty in parametric models. The method was thoroughly tested in simulations of the ozonolysis of oleic acid.
- Application of parametric equations and neural network models for the modelling of gas exchange rates of biological soil crusts to advance the calculation of the net primary production and long-term carbon balance of dryland ecosystems. Biological soil crusts, communities of photoautotrophic and heterotrophic organisms form a common ecological feature in dryland areas across the globe and are an important factor for carbon balance and cycling. NN and parametric equation models trained on laboratory data are capable of describing carbon dioxide CO2 gas exchange rates of various types of biological soil crusts based on the prevailing environmental conditions. The models are accurate, versatile and are applied to investigate the effect of ambient CO2 concentrations on biological soil crusts in a follow-up study.xiii, 182 Seiten ; Illustrationen, Diagramm
Band topology and exchange effects in compensated Eu-based compounds
No full textVI, 94 Seiten ; Illustrationen, Diagramm
Einfluss der neutrophilen Granulozyten auf die Blut- Hirn- Schranken- Störung in einem experimentellen Modell der Subarachnoidalblutung
No full textunclear. In the pathophysiology of other diseases, a neutrophil-induced disruption of the blood-brain barrier (BBB) was shown to play a major role. We therefore examined the effect of neutrophils on the BBB in the first 24 hours after SAH in a murine endovascular filament perforation model of SAH.
Methods
SAH was induced in C57BL/6N mice by endovascular filament perforation. Neutropenia was induced by anti-Ly6G antibody injection 12 h prior to surgery, successful induction of neutropenia was verified by differential leukocyte counts at the end of the experiment. Animals were sacrificed at 15 min, 3 h, and 24 h after SAH. The brains were dissected and frozen in powdered dry ice, cryosections were obtained, and IgG fluorescence staining was performed. Positive IgG fluorescence was taken as a surrogate parameter for BBB disruption. The area with BBB disruption was determined for the left hemisphere. Data are expressed in percent relative to the ipsilateral hemisphere. The Mann-Whitney U test was used for statistical analysis with p < 0.05 considered as statistically significant.
Results
51 animals were assigned to either sham surgery or SAH induction with or without prior induction of neutropenia. SAH induction without prior induction of neutropenia induced a sharp increase in the area with BBB disruption (SAH, 15 min: 6,27 ± 3,35%, 3 h: 16,02 ± 6,35%, 24 h: 21,71 ± 5,58%), which was not present after sham surgery (sham, 15 min: 5,16 ± 1,64%, 3 h: 5,93 ± 4,18%, 24 h: 6,65 ± 6,71%). After induction of neutropenia, SAH-induced disruption of the BBB was attenuated compared to SAH alone (SAH and neutropenia, 15 min: 2,36 ± 2%, 3 h: 8,66 ± 5,83%, 24 h: 5,42 ± 3,84%), which reached statistical significance at 24 h post-SAH.
Conclusion
Already in the first hours after SAH, neutrophils induce a disruption of the BBB. Targeting neutrophil function or neutrophil interaction with the neurovascular unit could therefore be a promising strategy to mitigate BBB disruption after SAH. More studies are needed to examine whether the early neutrophil-induced BBB disruption is the critical phenomenon that leads to activation of cerebral inflammation in the weeks after SAH.ca. 85 Seite
Irrational beliefs in Bahasa Malaysia and Mandarin speaking populations : the cross-cultural validation of the irrational performance beliefs inventory
No full textBackground
Irrational beliefs as conceptualized within Rational Emotive Behavior Therapy (REBT) are maladaptive ideas about the world that perpetuate ill mental health and psychological distress. However, our understanding of the role of irrational beliefs in psychopathology is heavily reliant on the data from Western samples, chiefly the United Kingdom and the United States. Thus, to help bridge the gap between East and West, we must first understand the extent to which our measures are suitable for cross-cultural purposes. In this article we present the translation and validity testing of two versions of the irrational Performance Beliefs Inventory (iPBI) – a Mandarin language version and a Bahasa Malaysia language version.
Methods
For this purpose, 239 Bahasa Malaysia speaking participants and 180 Mandarin speaking participants (f = 139, m = 280, Mage = 23.05, SDage = 6.02, age range: 16–50 years) took part in the study. After a detailed translation process, we carried out confirmatory factor analyses to test whether the expected four-factor-structure can be confirmed in these Bahasa Malaysia and Mandarin speaking subsamples.
Results
Results showed a partially inadequate model fit (Bahasa Malaysia version: CFI = .841, RMSEA = .072; Mandarin version: CFI = .866, RMSEA = .066). In addition, we conducted exploratory analyses and applied existing versions of the iPBI, namely the existing Thai and Korean versions, to our sample to examine whether they provide a better model fit. In addition, construct validity (i.e., convergent, divergent, and concurrent validity) indicated partial validity, with mixed relationships between irrational beliefs and trait anxiety, anger, and depression for the different iPBI versions.
Conclusion
The current findings indicate that further psychometric work is necessary before Bahasa Malaysia and Mandarin versions of the iPBI can be adequately applied in research and practice. We discuss possible shortcomings and provide suggestions for further research