13,056 research outputs found

    Arbeiten zur Optischen KohÀrenztomographie, Magnetresonanzspektroskopie und Ultrahochfeld-Magnetresonanztomographie

    Get PDF
    Abstrakt (Deutsch) Hintergrund: Die Multiple Sklerose ist eine der hĂ€ufigsten neurologischen Erkrankungen, die zu Behinderung bereits im jungen Erwachsenenalter fĂŒhren kann. Hierzu tragen im Krankheitsprozess sowohl neuroinflammatorische wie auch neurodegenerative Komponenten bei. Moderne bildgebende Verfahren wie die Ultrahochfeld-Magnetresonanztomographie (UHF-MRT), die Optische KohĂ€renztomographie (OCT) und die Magnetresonanzspektroskopie (MRS) können benutzt werden, um diese neurodegenerativen Prozesse nĂ€her zu charakterisieren und im zeitlichen Verlauf zu beobachten. Zielsetzung: Ziel ist es, die genannten Verfahren zur Charakterisierung von Kohorten von MS-Patienten einzusetzen und die Verfahren zueinander, sowie mit klinischen Parametern in Beziehung zu setzen oder diagnostisch zu nutzen. Methodik: Patienten mit Multipler Sklerose oder Neuromyelitis optica wurden klinisch-neurologisch, mit Optischer KohĂ€renztomographie, SehprĂŒfungen, Untersuchungen der visuell evozierten Potentiale (VEP), (Ultrahochfeld-) Magnetresonanztomographie und Magnetresonanzspektroskopie untersucht. Ergebnisse: Die in der Studie eingesetzten bildgebenden Verfahren konnten dazu beitragen, Neuroinflammation und Neurodegeneration bei an Multiple Sklerose erkrankten Patienten nĂ€her zu charakterisieren. So steht eine mittels OCT messbare VerdĂŒnnung retinaler Nervenfaserschichten (RNFL) in Zusammenhang mit dem per MRT gemessenen Hirnparenchymvolumen und Neurodegeneration anzeigenden Parametern, die mithilfe der Magnetresonanzspektroskopie untersucht wurden. Mithilfe der UHF-MRT konnte ein Zusammenhang zwischen dem Volumen und der entzĂŒndlichen LĂ€sionslast der Sehstrahlung, der RNFL-Dicke, VEP-Latenzen und EinschrĂ€nkungen des Sehvermögens dargestellt werden. Außerdem ließen sich mit der UHF-MRT auch neurogenerative Aspekte im Sinne von bleibenden Parenchymdefekten innerhalb entzĂŒndlicher LĂ€sionen und einer VerschmĂ€chtigung der Sehstrahlung nachweisen und die Detektion insbesondere kortikaler MS-LĂ€sionen wurde im Vergleich zur konventionellen MRT verbessert. Zusammenfassung: OCT, MRS und UHF-MRT sind Verfahren, die eine genauere Beschreibung von Neuroinflammation und Neurodegeneration bei MS-Patienten ermöglichen, wie hier vor allem fĂŒr die Sehbahn gezeigt wurde. Sie sind nichtinvasiv und lassen sich zur nĂ€heren Charakterisierung des aktuellen Zustandes und zur Beobachtung des Krankheitsverlaufs von MS-Patienten benutzen.Abstract (English) Background: Multiple sclerosis (MS) is the most common disabling neurologic disease, that causes impairment in younger people. Both neuroinflammatory and neurodegenerative processes contribute to the pathogenesis of multiple sclerosis. Innovative imaging methods, such as ultra-high field magnetic resonance tomography (UHF-MRI), optic coherence tomography (OCT) and magnetic resonance spectroscopy (MRS) can be used for characterizing these neurodegenerative processes in detail and over time course. Objective: To use the imaging methods mentioned above to further characterize cohorts of MS patients and to correlate the parameters with themselves as well as with clinical parameters and to evaluate their prognostic and diagnostic relevance. Methods: Patients with multiple sclerosis were examined clinically, by OCT, visual acuity testing, examination of visually evoked potentials, ultra high field magnetic resonance tomography and magnetic resonance spectroscopy. Results: The imaging methods used in these studies contributed to further characterize neuroinflammation und neurodegeneration in multiple sclerosis patients. A thinning of the retinal nerve fiber layer (RNFL) is correlated with brain parenchyma volume measured by MRI, and markers indicating ongoing neurodegenerative processes as detected by MRS. Using UHF-MRI, a correlation between optic radiation properties (such as inflammatory lesion load and its volume) and RNFL thickness, VEP latencies and visual impairment could be demonstrated. Furthermore, UHF-MRI demonstrated neurodegenerative aspects such as parenchymal defects within inflammatory lesions, an optic radiation thinning and allowed a more precise detection of MS lesions than conventional MRI, in particular cortical grey matter lesions. Summary: OCT, MRS and UHF-MRI are feasible methods to provide a more detailed description of neuroinflammation and neurodegeneration in MS patients, as demonstrated in these studies particularly for the visual pathway. They are non-invasive and can be utilized for clinical to study the disease course and also in differential diagnostic procedures

    Mummies and masquerades: English and Caribbean connections

    Get PDF
    The composite mumming play script that the Ecclesfield-based Victorian children's author Juliana Horatia Ewing published in 1884 found its way to St. Kitts and Nevis in the Caribbean, where it was it was taken up enthusiastically by the black population as one of its Christmas Sports. The Mummies continue to act (and dance) to this day. Economic migrants took the Christmas Sports in turn to the Dominican Republic, in particular around the town of San Pedro de Macoris, where the performers recently gained a UNESCO Cultural Heritage Award. This paper derives from a presentation based around two videos, presented here as story boards. Millington introduces Ewing's play, and footage of the St Kitts Mummies and the Bull Play filmed by Joan McMurray. James continues the story by introducing footage of the related tradition from the Dominican Republic called the Wild Indians in English and Los Guloyas (the Goliaths) in Spanish

    Spontaneous Emission in Quantum Walks of a Kicked Bose-Einstein Condensate

    Full text link
    We analytically investigate the recently proposed and implemented discrete-time quantum walk based on a kicked Bose-Einstein condensate. We extend previous work on the effective dynamics by taking into account spontaneous emission due to the kicking light. Spontaneous emission affects both the internal and external degrees of freedom, arising from the entanglement between them during the walk dynamics. The result is a measurable degrading of the experimental walk signal that we characterise.Comment: comments and suggestions welcom

    Comrades or Foes: Did the Russians Break the Law or New Ground for the First Amendment?

    Get PDF
    This Article discusses the recent decision by the United States Federal Government to indict more than a dozen Russian nationals for conspiracy to defraud the United States of America. The Government accused the Russians of staging protests, distributing false propaganda, and spreading political messages and ideologies online in an effort to affect the outcome of the 2016 Presidential Election. We argue that while the Defendants violated several other laws, the majority of the acts the Government classifies as a conspiracy to defraud the United States should not be considered criminal. Rather, these acts are protected political speech under the First Amendment of the United States Constitution because the Russians engaged in conduct that is crucial to political discourse in a Democracy and which the Founding Fathers intended to protect. Therefore, prosecution of the Russian Defendants on that basis should cease
    • 

    corecore