2,974 research outputs found

    Two-Particle Quantum Interference and Bell’s Theorem

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    Bell’s theorem is among the most challenging consequences of quantum mechanics. In this thesis, the connection between Bell’s theorem and quantum interference is investigated by asking the question, whether Bell’s theorem can be proven on the basis of two-particle quantum interference. In the first part of this thesis the meaning of quantum interference and Bell’s Theorem for the discussion about the interpretation of quantum mechanics is retraced. By considering three major branches of interpretations, the conceptual diculties, which are encountered in the face of quantum interference and Bell’s theorem, are discussed. In addition, an epistemological argument for the inherent indeterminism of certain quantum mechanical phenomena is presented. In the second part of this thesis a two-particle quantum interference thought experiment is developed and it is shown that Bell’s theorem can be proven from two-particle quantum interference, if certain quantum mechanical phenomena in the experiment are inherently indeterministic

    Kappa-symmetric deformations of M5-brane dynamics

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    We calculate the first supersymmetric and kappa-symmetric derivative deformation of the M5-brane worldvolume theory in a flat eleven-dimensional background. By applying cohomological techniques we obtain a deformation of the standard constraint of the superembedding formalism. The first possible deformation of the constraint and hence the equations of motion arises at cubic order in fields and fourth order in a fundamental length scale ll. The deformation is unique up to this order. In particular this rules out any induced Einstein-Hilbert terms on the worldvolume. We explicitly calculate corrections to the equations of motion for the tensor gauge supermultiplet.Comment: 17 pages. Additional comments in section

    Intranasal oxytocin reduces provoked symptoms in female patients with posttraumatic stress disorder despite exerting sympathomimetic and positive chronotropic effects in a randomized controlled trial

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    Background: Posttraumatic stress disorder (PTSD) is a severe psychiatric disease accompanied by neuroendocrine changes such as adrenergic overdrive and hence an elevated cardiovascular morbidity. Current pharmacotherapeutic options for PTSD are less than suboptimal, necessitating the development of PTSD-specific drugs. Although the neuropeptide oxytocin has been repeatedly suggested to be effective in PTSD treatment, there are, to our knowledge, only three studies that have assessed its efficacy on the intensity of PTSD symptoms in PTSD patients - among them one symptom provocation study in male veterans. Methods: To evaluate for the first time how oxytocin influences the intensity of provoked PTSD symptoms and, furthermore, cardiac control in female PTSD patients, we assessed their psychic and cardiac response to trauma-script exposure with and without oxytocin pretreatment in a double-blind randomized placebo-controlled study. We used a within-subject design to study 35 female PTSD patients who received oxytocin and placebo in a 2-week interval. Furthermore, we performed a small pilot study to get an idea of the relation of the stress-modulated endogenous oxytocin levels and heart rate - we correlated oxytocin serum levels with the heart rate of 10 healthy individuals before and after exposure to the Trier Social Stress Test (TSST). Results: Intranasal oxytocin treatment was followed by a reduction of provoked total PTSD symptoms, in particular of avoidance, and by an elevation in baseline and maximum heart rate together with a drop in the pre-ejection period, a marker for sympathetic cardiac control. Furthermore, we found a positive correlation between endogenous oxytocin levels and heart rate both before and after TSST challenge in healthy control subjects. Conclusions: This study provides the first evidence that oxytocin treatment reduces the intensity of provoked PTSD symptoms in female PTSD patients. The small size of both samples and the heterogeneity of the patient sample restrict the generalizability of our findings. Future studies have to explore the gender dependency and the tolerability of the oxytocin- mediated increase in heart rate

    Repräsentative SMART-Nachhaltigkeitsbewertung der Bio Suisse-Betriebe. Kurzbericht 2018

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    Die Knospe gilt als Garant für eine nachhaltige Landwirtschaft. Doch wie nachhaltig wirtschaften die Knospe-Höfe tatsächlich,was läuft gut, wo gibt es Verbesserungspotential? Diesen Fragen gingen das FiBL und die SFS im Auftrag von Bio Suisse auf den Grund. Zum Einsatz kam dabei SMART (Sustainability Monitoring and Assessment RouTine), ein Instrument, welches das FiBL zur ganzheitlichen Nachhaltigkeitsanalyse und Bewertung von landwirtschaftlichen Betrieben und Lebensmittelunternehmen entwickelt hat. Die Bewertung beruht auf einer Betriebsbesichtigung und einem etwa zwei- bis dreistündigen Interview mit den Betriebsleitern zu verschiedenen für die Landwirtschaft relevanten Themenbereichen. Innerhalb von drei Jahren wurden so 185 Höfe auf ihre Nachhaltigkeit hin untersucht. Die Stichprobe wurde so gewählt, dass alle Betriebstypen und Landwirtschaftszonen abgebildet wurden. Zu den Projektzielen gehörten: - Repräsentative Bewertung der Nachhaltigkeitsleistungen der Knospe-Betriebe durch eine externe Institution. - Ermöglichung der kontinuierlichen Entwicklung der Betriebe und Sicherstellung der Zukunftsfähigkeit der Bio Suisse Betriebe sowie der Marke Knospe. - Erarbeitung einer glaubwürdigen Informationsbasis zur Kommunikation der Nachhaltigkeit von Knospe-Betrieben. Die Ergebnisse sollen sowohl für die Verbesserung des Beratungs- und Schulungsangebots im Bereich Nachhaltigkeit als auch für die strategische Weiterentwicklung des Verbands genutzt werden

    String Loop Corrections to Kahler Potentials in Orientifolds

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    We determine one-loop string corrections to Kahler potentials in type IIB orientifold compactifications with either N=1 or N=2 supersymmetry, including D-brane moduli, by evaluating string scattering amplitudes.Comment: 80 pages, 4 figure

    Electromagnetic Calorimeter for HADES

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    We propose to build the Electromagnetic calorimeter for the HADES di-lepton spectrometer. It will enable to measure the data on neutral meson production from nucleus-nucleus collisions, which are essential for interpretation of dilepton data, but are unknown in the energy range of planned experiments (2-10 GeV per nucleon). The calorimeter will improve the electron-hadron separation, and will be used for detection of photons from strange resonances in elementary and HI reactions. Detailed description of the detector layout, the support structure, the electronic readout and its performance studied via Monte Carlo simulations and series of dedicated test experiments is presented. The device will cover the total area of about 8 m^2 at polar angles between 12 and 45 degrees with almost full azimuthal coverage. The photon and electron energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV]) which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in Ni+Ni collisions at 8 AGeV. A purity of the identified leptons after the hadron rejection, resulting from simulations based on the test measurements, is better than 80% at momenta above 500 MeV/c, where time-of-flight cannot be used.Comment: 40 pages, 38 figures version2 - the time schedule added, information about PMTs in Sec.III update

    Automatic guiding of the primary image of solar Gregory telescopes

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    The primary image reflected from the field-stop of solar Gregory telescopes is used for automatic guiding. This new system avoids temporal varying influences from the bending of the telescope tube by the main mirror's gravity and from offsets between the telescope and a separate guiding refractor. The required stiffness of the guider mechanics and the small areas of the sensors demand small f-numbers for the guider optics, which cause problems with the image quality and with heat. Problems also arise from the imaging of the pinhole in the telescope's field stop. The corresponding lack of image information at that location can be reduced numerically by Fourier methods much more effectively than with profile centering methods. Several types of such guiders are tested, a final equipment, now installed at the Gregory telescopes at Tenerife and at Locarno, is described
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