1,569 research outputs found

    A Mechanism for Photoinduced Effects In Tetracyanoethylene-Based Organic Magnets

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    The photoinduced magnetism in manganese-tetracyanoethylene (Mn-TCNE) molecule-based magnets is ascribed to charge-transfer excitations from manganese to TCNE. Charge-transfer energies are calculated using Density Functional Theory; photoinduced magnetization is described using a model Hamiltonian based on a double-exchange mechanism. Photoexciting electrons from the manganese core spin into the lowest unoccupied orbital of TCNE with photon energies around 3 eV increases the magnetization through a reduction of the canting angle of the manganese core spins for an average electron density on TCNE less than one. When photoexciting with a smaller energy, divalent TCNE molecules are formed. The delocalization of the excited electron causes a local spin flip of a manganese core spin.Comment: 4 pages, 4 figure

    Symmetry Violation in a Superconducting Film with a Square Array of Ferromagnetic Dots

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    We study the equilibrium state of a superconducting film covered with a regular square array of perpendicularly magnetized magnetic dots. The dots induce vortices in the film directly under them and antivortices between the dots. We show that the symmetry of the dot array is spontaneously violated by the vortices. The positions of the vortices and the antivortices depend on the magnetization and the size of the dots.Comment: 6 pages, 3 figure

    The examination of gathering points' capacity regarding mobility and accessibility: Case of Bayrakli district

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    The concept of accessibility that bases on continuing the flow of people, goods and services uninterruptedly is discussed as "maximum contact by minimum facility". This concept which is related with the distance has been evaluated various criteria such as physical, economic, perceptual, temporal, etc. Several assignations (optimum location, minimum distance, best distribution method, etc.) have revealed the importance of gathering points in terms of proceeding the disaster management properly. The origin point of linking "accessibility" and "transportation network" is the mobility which reveals as accessing people to adequate gathering points and services in the shortest time. These gathering points which are determined due to the specific criteria and also referred to the social infrastructure areas have a vital importance when any disaster or emergencies occur; so the site selection, availability and accessibility of these areas become extremely significant. The aim of this study is to examine the accessibility of gathering points in Bayrakli district located in Izmir city by taking minimum standards and also some recommendations into consideration. The spatial analyses based on current and potential gathering points are carried out via ArcMap software. The current and potential gathering points in Bayrakli district are examined in terms of accessibility their capacity for each neighbourhood due to their spatial distribution. According to the results, each gathering points in neighbourhoods cannot be accessible in the shortest duration by walking and also the current urban pattern affects the capacity parameter regarding the accessibility and mobility significantly. © Authors 2018. CC BY 4.0 License

    Ferromagnetic Annulus And Superconducting Vortices

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    The screening currents induced in a superconducting film by a magnetic annulus whose magnetization is perpendicular to the superconductor are calculated. We show that close to the superconductor transition temperature TcT_c particular values of the magnetization and radii of the annulus make the creation of superconducting vortices energy favorable. We also show that the magnetic annulus offers an alternative tool for vortex pinning in the superconductor. Statistical mechanical properties of this system are discussed.Comment: 4 pages, 2 figures, submitted to PR

    Perinatal mental disorders in Switzerland : prevalence estimates and use of mental-health services

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    Background: Perinatal mental disorders (PMDs) are the most common complication of pregnancy and the first postpartum year. Since PMD prevalence and use of mental-health services by perinatal women in Switzerland are unknown, we analysed existing health statistics. Methods: We used statistics from a large health insurance company, hospitals and freelance midwives. We assessed the annual rates of mental healthcare use in perinatal women (n = 13 969). We ascertained the annual rates of PMD treatment in obstetric inpatients (n = 89 699), and annual rates of PMD records by freelance midwives (n = 57 951). In 15 104 women who gave birth in 2012 or 2013, we assessed use of mental-healthcare before and during pregnancy, and in the postpartum year. For the same sample, we determined proportions of medication and consultation treatments. We used multiple regression analysis to estimate the influence of PMD on overall healthcare costs of mandatory health insurance. Results: The annual rate of mental-healthcare use by perinatal women was 16.7%. The annual rate of PMD treatment in obstetric inpatients was 1.1%. The annual rate of PMD records in the midwifery care setting was 2.9%. Women with PMD use mental health services mainly in non-obstetric outpatient settings. Medication was the most frequent treatment. Primary care providers and mental health specialists contributed almost equally to consultation treatments. PMD during pregnancy raised overall costs of healthcare in the postpartum year by 1214 Swiss francs. Conclusions: Health-system research and perinatal healthcare should take into consideration the high prevalence of PMD. Real PMD prevalence may be even higher than our data suggest and could be assessed with a survey using our model of PMD prevalence

    Die Landwirtschaft und andere Einflussgrößen auf die Bevölkerungsentwicklung im ländlichen Raum

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    Factor analysis and regression analysis is used to estimate population growth and migration into and out of rural agreas in Switzerland between 1990 and 2000. Farm households contribute to an above average birth rate. However, there is a net migration out of rural areas.mesoeconomics, economic structures, socio-economics, Community/Rural/Urban Development,
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