212 research outputs found

    Entwicklung eines mediendidaktischen Konzepts zur Erstellung eines internetgestützten Lernprogramms über Struktur und Funktion der Orchideenmykorrhiza – Fachwissenschaftliche Analyse, didaktische Aufbereitung und mediale Umsetzung

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    Die biologiedidaktische Dissertation befasst sich in erster Linie mit der Struktur und Funktion der Orchideenmykorrhiza, d.h. mit dem symbiotischen Zusammenleben zwischen Orchideenwurzeln und Pilzen. Nachdem die Bedeutung des Online-Lernens vor allem im Hochschulbereich stark zunimmt und didaktisch ausgereifte Lernangebote fehlen, wird versucht, ausgehend von einem mediendidaktischem Konzept, die komplexe Thematik mit Hilfe eines internetgestützten Lernprogramms mit dem Namen "Orchideenmykorrhiza-Online" zu visualisieren. Hierbei wird geprüft, ob durch die Berücksichtigung mediendidaktischer und softwareergonomischer Gestaltungsrichtlinien Lernprozesse via Internet optimiert werden können. Die wissenschaftliche Abhandlung ist in drei Teilbereiche gegliedert. Im ersten Abschnitt erfolgt ein detaillierter Überblick über den aktuellen Forschungsstand der Orchideenmykorrhiza als wichtige Voraussetzung für eine Online-Präsentation. Die darauf folgende mediendidaktische Analyse enthält wichtige Aspekte für die Umsetzung von Darstellungsformen wie Text, Bild und Animation sowie Gestaltungskriterien für eine Realisierung von Interaktions-formen (z. B. Navigation) im Internet. Der dritte Teil beschäftigt sich schließlich mit der Konzeption, Umsetzung und Evaluation von "Orchideenmykorrhiza-Online"

    Molecular analysis of desmoid tumors with a high-density single-nucleotide polymorphism array identifies new molecular candidate lesions

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    Background: Desmoid tumors are neoplastic proliferations of connective tissues. The mutation status of the gene coding for catenin (cadherin-associated protein) beta 1 (CTNNB1) and trisomy 8 on the chromosomal level have been described to have prognostic relevance. Patients and Methods: In order to elucidate new molecular mechanisms underlying these tumors, we carried out a molecular analysis with a genome-wide human high-density single-nucleotide polymorphism (SNP) array, in 9 patients. Results: Single samples showed numerical aberrations on chromosomes (Chrs) 20 and 6 with either trisomy 20 or monosomy 6. No trisomy 8 could be detected. Recurrent heterozygous deletions were found in Chr 5q (including the APC gene locus, n = 3) and Chr 8p23 (n = 4, containing coding regions for the potential tumor suppressor gene CSMD1). This novel deletion in 8p23 showed an association with local recurrence. In addition, structural chromosomal changes (gain of Chrs 8 and 20) were found in a minority of cases. Conclusion: The genomic alteration affecting the candidate gene CSMD1 could be important in the development of desmoid tumors

    Prognostic assessment of liver cirrhosis and its complications: current concepts and future perspectives

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    Liver cirrhosis is an irreversible stage of chronic liver disease with varying clinical course. Acute decompensation of liver cirrhosis represents a watershed in prognosis and is characterized by the occurrence of clinical complications such as ascites, jaundice, hepatic encephalopathy, infections, or portal-hypertensive hemorrhages. Emergent data indicate that an acute decompensation can be subdivided into stable decompensated cirrhosis (SDC), unstable decompensated cirrhosis (UDC), pre-acute-on chronic liver failure (pre-ACLF) and acute-on chronic liver failure (ACLF), while the mortality risk varies greatly between the respective subgroups. ACLF is the most severe form of acutely decompensated cirrhosis and characterized by the development of organ failure(s) and a high short-term mortality. Due to the dynamic disease course of acute decompensation, it is paramount to detect patients at particular risk for severe complications those at high risk for developing ACLF as early as possible in order to initiate optimal management. This review describes new concepts and perspectives in the definition and classification of decompensated cirrhosis and provides on overview on emerging predictive scoring systems, non-invasive measurement methods and new biomarkers, which allow an early identification of patients with acute decompensation at risk

    Variational quantum simulation of U(1) lattice gauge theories with qudit systems

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    Lattice gauge theories are fundamental to various fields, including particle physics, condensed matter, and quantum information theory. Recent progress in the control of quantum systems allows for studying Abelian lattice gauge theories in table-top experiments. However, several challenges remain, such as implementing dynamical fermions in higher spatial dimensions and magnetic field terms. Here, we map D-dimensional U(1) Abelian lattice gauge theories onto qudit systems with local interactions for arbitrary D. We propose a variational quantum simulation scheme for the qudit system with a local Hamiltonian, that can be implemented on a universal qudit quantum device as the one developed in [Nat. Phys. 18, 1053-1057 (2022)]. We describe how to implement the variational imaginary-time evolution protocol for ground state preparation as well as the variational real-time evolution protocol to simulate non-equilibrium physics on universal qudit quantum computers, supplemented with numerical simulations. Our proposal can serve as a way of simulating lattice gauge theories, particularly in higher spatial dimensions, with minimal resources, regarding both system sizes and gate count

    Higher-order mean-field theory of chiral waveguide QED

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    Waveguide QED with cold atoms provides a potent platform for the study of non-equilibrium, many-body, and open-system quantum dynamics. Even with weak coupling and strong photon loss, the collective enhancement of light-atom interactions leads to strong correlations of photons arising in transmission, as shown in recent experiments. Here we apply an improved mean-field theory based on higher-order cumulant expansions to describe the experimentally relevant, but theoretically elusive, regime of weak coupling and strong driving of large ensembles. We determine the transmitted power, squeezing spectra and the degree of second-order coherence, and systematically check the convergence of the results by comparing expansions that truncate cumulants of few-particle correlations at increasing order. This reveals the important role of many-body and long-range correlations between atoms in steady state. Our approach allows to quantify the trade-off between anti-bunching and output power in previously inaccessible parameter regimes. Calculated squeezing spectra show good agreement with measured data, as we present here.Comment: 16+9 pages, 9+2 figure

    eXamine: Visualizing annotated networks in Cytoscape [version 1; referees: 1 approved, 2 approved with reservations]

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    eXamine is a Cytoscape app that displays set membership as contours on top of a node-link layout of a small graph. In addition to facilitating interpretation of enriched gene sets of small biological networks, eXamine can be used in other domains such as the visualization of communities in small social networks. eXamine was made available on the Cytoscape App Store in March 2014, has since registered more than 7,200 downloads, and has been highly rated by more than 25 users. In this paper, we present eXamine's new automation features that enable researchers to compose reproducible analysis workflows to generate visualizations of small, set-annotated graphs

    Tinea genitalis: a new entity of sexually transmitted infection? Case series and review of the literature

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    OBJECTIVE Investigation on recent cases of tinea genitalis after travelling to South East Asia. METHODS Patients with tinea in the genital region, which emerged after sex in South East Asia, underwent further assessment including microscopy, cultures and DNA analyses. RESULTS The case series includes seven patients. In six patients, Trichophyton interdigitale (former Trichophyton mentagrophytes) was detected. Three patients suffered from a severe inflammatory reaction of the soft tissue and two of them needed hospitalisation due to severe pain. In four patients, cicatrising healing was noticed. Five patients were declared incapacitated for work. CONCLUSIONS Sexual activity should be considered as a potentially important and previously underappreciated means of transmission of T. interdigitale. To avoid irreversible scarring alopecia, prompt initiation of antifungal treatment is essential and adequate isolation and identification of the pathogen is mandatory

    Eemian landscape response to climatic shifts and evidence for northerly neanderthal occupation at a palaeolake margin in northern germany

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    The prevailing view suggests that the Eemian interglacial on the European Plain was characterized by largely negligible geomorphic activity beyond the coastal areas. However, systematic geomorphological studies are sparse. Here we present a detailed reconstruction of Eemian to Early Weichselian landscape evolution in the vicinity of a small fingerlake on the northern margin of the Salzwedel Palaeolake in Lower Saxony (Germany). We apply a combination of seismics, sediment coring, pollen analysis and luminescence dating on a complex sequence of colluvial, paludal and lacustrine sediments. Results suggest two pronounced phases of geomorphic activity, directly before the onset and at the end of the Eemian period, with an intermediate period of pronounced landscape stability. The dynamic phases were largely driven by incomplete vegetation cover, but likely accentuated by fluvial incision in the neighbouring Elbe Valley. Furthermore, we discovered Neanderthal occupation at the lakeshore during Eemian pollen zone (PZ) E IV, which is chronologically in line with other known Eemian sites of central Europe. Our highly‐resolved spatio‐temporal data substantially contribute to the understanding of climate‐induced geomorphic processes throughout and directly after the last interglacial period. It helps unraveling the landscape dynamics between the coastal areas to the north and the loess belt to the south
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