40 research outputs found

    An experimental and theoretical guide to strongly interacting Rydberg gases

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    We review experimental and theoretical tools to excite, study and understand strongly interacting Rydberg gases. The focus lies on the excitation of dense ultracold atomic samples close to, or within quantum degeneracy, to high lying Rydberg states. The major part is dedicated to highly excited S-states of Rubidium, which feature an isotropic van-der-Waals potential. Nevertheless, the setup and the methods presented are also applicable to other atomic species used in the field of laser cooling and atom trapping.Comment: 23 pages, 22 figures, tutoria

    Lifetimes of ultralong-range Rydberg molecules in vibrational ground and excited state

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    Since their first experimental observation, ultralong-range Rydberg molecules consisting of a highly excited Rydberg atom and a ground state atom have attracted the interest in the field of ultracold chemistry. Especially the intriguing properties like size, polarizability and type of binding they inherit from the Rydberg atom are of interest. An open question in the field is the reduced lifetime of the molecules compared to the corresponding atomic Rydberg states. In this letter we present an experimental study on the lifetimes of the ^3\Sigma (5s-35s) molecule in its vibrational ground state and in an excited state. We show that the lifetimes depends on the density of ground state atoms and that this can be described in the frame of a classical scattering between the molecules and ground state atoms. We also find that the excited molecular state has an even more reduced lifetime compared to the ground state which can be attributed to an inward penetration of the bound atomic pair due to imperfect quantum reflection that takes place in the special shape of the molecular potential

    Analysis of Motor Function in the Tg4-42 Mouse Model of Alzheimer’s Disease

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    Alzheimer’s disease (AD) is a neurodegenerative disorder and the most common form of dementia. Hallmarks of AD are memory impairments and cognitive deficits, but non-cognitive impairments, especially motor dysfunctions are also associated with the disease and may even precede classic clinical symptoms. With an aging society and increasing hospitalization of the elderly, motor deficits are of major interest to improve independent activities in daily living. Consistent with clinical findings, a variety of AD mouse models develop motor deficits as well. We investigated the motor function of 3- and 7-month-old Tg4-42 mice in comparison to wild-type controls and 5XFAD mice and discuss the results in context with several other AD mouse model. Our study shows impaired balance and motor coordination in aged Tg4-42 mice in the balance beam and rotarod test, while general locomotor activity and muscle strength is not impaired at 7 months. The cerebellum is a major player in the regulation and coordination of balance and locomotion through practice. Particularly, the rotarod test is able to detect cerebellar deficits. Furthermore, supposed cerebellar impairment was verified by 18F-FDG PET/MRI. Aged Tg4-42 mice showed reduced cerebellar glucose metabolism in the 18F-FDG PET. Suggesting that, deficits in coordination and balance are most likely due to cerebellar impairment. In conclusion, Tg4-42 mice develop motor deficits before memory deficits, without confounding memory test. Thus, making the Tg4-42 mouse model a good model to study the effects on cognitive decline of therapies targeting motor impairments

    Digitalisierung und Demokratie

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    Die Digitalisierung spielt bei den Prozessen und Entwicklungen in einer Demokratie eine immer größere Rolle. Denn Digitalisierung erweitert die Möglichkeiten der Information, Kommunikation und Partizipation. Gleichzeitig können digitale Technologien zu einer schnellen Verbreitung von Falschinformationen beitragen und bergen ein Potenzial für Meinungsmanipulation, zum Beispiel vor Wahlen. Dieses Spannungsfeld ist Thema der Stellungnahme "Digitalisierung und Demokratie". Darin analysieren die Autorinnen und Autoren Aspekte des Zusammenspiels von Digitalisierung und Demokratie. Darauf aufbauend formulieren sie Handlungsempfehlungen zur Gestaltung künftiger Entwicklungen durch Politik, Recht und Zivilgesellschaft

    TO ERADICATION OF VOLTAGE SAG AND HARMONICS IN DISTRIBUTION SYSTEM USING DVR WITH CAPACITOR COMPENSATION SCHEME

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    Power Quality (PQ) is that the most vital perspectives on transmission and distribution ranges. The availability of high-grade electric powered offerings wished for the customers illustrates this idea. The voltage sag and swell square degree the most not unusual PQ problems that in particular rise up in the distribution systems because of the truth that it's going to cause tool tripping, failure of stress systems, closure for home and business instrumentality. The Dynamic Voltage Restorer (DVR) associated nonparallel has amazing dynamic talents and is a flexible solution for PQ troubles. Ultra-capacitors (UCAP) have quality developments like excessive strength and espresso electricity density important for the mitigation of voltage sag and swell. This paper offers AN extended DVR topology capable of handing over deep, prolonged mitigation for power terrific troubles. Within the planned DVR, UCAP is employed as strength storage because it offers immoderate electricity in a totally short c software language length of it gradual. The DVR is protected into Ultra capacitor via a bifacial DC-DC converter which facilitates in supplying a rigid dc-link voltage and conjointly enables in compensating transient voltage sag and voltage swell. PI Controller is hired in DVR for electricity exceptional improvement. The simulation model for the proposed device has been superior in MATLAB and therefore the performance over famous DVR is legitimate with the effects obtained

    Guided de-escalation of antiplatelet treatment in patients with acute coronary syndrome undergoing percutaneous coronary intervention (TROPICAL-ACS): a randomised, open-label, multicentre trial

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    The preponderance of the kaloric nystagmus structured in an unilateral preponderance and directional preponderance

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    Bei dieser statistischen Auswertung wurde das klinische Bild der Seiten- und Richtungsenthemmung miteinander verglichen. Die gewonnenen Daten stammten dabei ausnahmslos aus den für jeden Patienten angelegten Anamnesebogen NODEC III. Hier sind nicht nur die persönlichen Daten und subjektiven Beschwerden des Patienten dokumentiert, sondern auch die objektiven äquilibriometrischen Untersuchungswerte. Die Datenerhebung erfolgte dabei aus dem Patientenstamm der Neurootologie Würzburg. Das Gesamtkollektiv besteht in dieser Untersuchung aus 75 richtungsenthemmten und 75 seitenenthemmten Schwindelpatienten. Anhand eines PCs wurde mit dem Tabellenkalkulationsprogramm EXCEL 2000 (9.0.2812) gruppiert, sortiert und anschließend statistisch ausgewertet. Aus den gebildeten Mittel- und Prozentwerten konnte eine vergleichende Gesamtstatistik beider Hauptkollektive erstellt werden. Die so gewonnenen Vergleichsdaten konnten durch die Bildung von spezifischen, korrespondierenden Unterkollektiven nach verschiedenen Gesichtspunkten verifiziert werden. Auch wurde zusätzlich die Richtungs- und Seitenenthemmung in zwei links- und zwei rechtsenthemmte Untergruppen weiter unterteilt und konnte so kollektivintern mehrfach miteinander verglichen werden. Darüber hinaus wurden repräsentative Fälle der Richtungs- und Seitenenthemmung nach rechts beziehungsweise links in Form von einzelnen Kasuistiken vorgestellt.In this statistical evaluation the clinical group of patients with a directional preponderance was compared with patients that showed a unileteral preponderance in the caloric electronystagmography. The analysed data based unexceptional on the anamnestic question paper NODEC III. Here are not only the personal facts and the individual medical conditions of each person but also the objective equilibriometric tests documented. The significant data collection was selected out of a patient base of the neorootology section of the Julius Maximilian University Würzburg. The overall collective exists out of 75 vertigo-patients with a directional and 75 with a unilateral preponderance. The collective was grouped and sorted with a personal computer and the chartcalculation program EXCEL 2000 (9.0.2812) bevor it was statistical analysed. The middle- and percentage value made a statistical comparison of both main collectives possible. The result of the compared data-base could be verified with the creation of specific, corresponding subcollectives with different perspectives. The directional and unilateral preponderance to the left and the directional and unilateral preponderance to the right were also subdivided in two significant soupgroups. This made a multiple collective-intern comparison possible. Four representive clinical cases of the directional and unilateral preponderance to the left and to the right are shown in 4 single casuistics

    The Impact of Phenological Developments on Interferometric and Polarimetric Crop Signatures Derived from Sentinel-1: Examples from the DEMMIN Study Site (Germany)

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    This study explores the potential of Sentinel-1 Synthetic Aperture Radar (SAR) to identify phenological phases of wheat, sugar beet, and canola. Breakpoint and extreme value analyses were applied to a dense time series of interferometric (InSAR) and polarimetric (PolSAR) features recorded during the growing season of 2017 at the JECAM site DEMMIN (Germany). The analyses of breakpoints and extrema allowed for the distinction of vegetative and reproductive stages for wheat and canola. Certain phenological stages, measured in situ using the BBCH-scale, such as leaf development and rosette growth of sugar beet or stem elongation and ripening of wheat, were detectable by a combination of InSAR coherence, polarimetric Alpha and Entropy, and backscatter (VV/VH). Except for some fringe cases, the temporal difference between in situ observations and breakpoints or extrema ranged from zero to five days. Backscatter produced the signature that generated the most breakpoints and extrema. However, certain micro stadia, such as leaf development of BBCH 10 of sugar beet or flowering BBCH 69 of wheat, were only identifiable by the InSAR coherence and Alpha. Hence, it is concluded that combining PolSAR and InSAR features increases the number of detectable phenological events in the phenological cycles of crops
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