Patterns of childbearing in Russia 1994 - 1998

In this paper we analyze the determinants of births in Russia in the 1990s and the changes in their effects since the 1980s and factors influencing fertility intentions in the 1990s. In the first part, based on the current social and economic situation in Russia, specific hypotheses for different parities (realized and intended fertility) are developed and subsequently tested by using logistic regression methods. On the basis of the Russian Longitudinal Monitoring Survey (RLMS) we find that the social differentiation that took place in Russia in the 1990s resulted in an increasing importance of economic conditions for a first, second or third birth. The same applies to parity-specific intentions.

Grating Coupling To Surface Phonon Polaritons

Ein Kernziel der Nanophotonik ist die Lokalisation von Licht mithilfe von Strukturen, die kleiner sind als die Lichtwellenl¨ ange, um neuartige lichtbasierte Technologien zu entwickeln. Optische Polaritonen stellen einen Weg dar, das konventionelle Brechungslimit zu umgehen, Licht zu lokalisieren und die damit einhergehenden starken Feld¨ uberh¨ ohungen zu erzeugen. Zu diesem Zweck wurden in den vergangenen Jahrzehnten Oberfl¨ achenplasmon-Polaritonen(engl. Surface Plasmon Polaritons, SPPs) ausgiebig studiert. Diese SPPs k¨ onnen in Edelmetalloberfl¨ achen angeregt werden, sind durch ihre kurze Lebenszeit jedoch stark limitiert. Eine in dieser Arbeit verwendete Alternative mit deutlich l¨ angerer Lebenszeit stellen Oberfl¨ achenphononen-Polaritonen (engl. Surface Phonon Polaritons, SPhPs). SPhPs sind gekoppelte Moden aus Phononen und Photonen. Diese Moden werden an der Oberfl¨ ache von einem polaren Dielektrikum mithilfe von Infrarotstrahlung angeregt. Fokus dieser Arbeit liegt auf der Anregung solcher SPhPs in der Oberfl¨ ache eines Siliciumcarbidkristalls (SiC) mithilfe eines auf der Oberfl¨ ache installierten Gitters. Hierbei dient das Gitter dazu, der eingehenden Strahlung zus¨ atzlichen Impuls parallel zur Oberfl¨ ache zu geben. Aufgrund der Dispersion des SPhPs kann nur durch diesen Impulsstoß Licht eingekoppelt werden. In dieser Arbeit wird der Einfluss verschiedener Gitterparameter auf die Kopplungseffizienz von infrarotem Licht an das SPhP untersucht. Zu diesem Zweck wurden Simulationen f¨ ur ein Gitter aus reinem SiC und einem Goldgitter durchgef¨ uhrt. Um die Validit¨ at der Simulationsergebnisse zu untersuchen wurden im Rahmen dieser Arbeit zwei solche Gittersysteme vermessen. Das reine SiC-Gitter wurde am ZELMI-Institut der Technischen Universit¨ at Berlin mit einem fokusierten Ionenbeam hergestellt. Das Goldgitter wurde in einer Kollaboration mit der Gruppe von Prof. Dr. M¨ unzenberger an der Universit¨ at Greifswald produziert. Als infrarote Lichtquelle zur Anregung der Moden diente der Freie Elektronenlaser des Fritz-Haber Institutes. Aus den Messergebnissen lies sich schlussfolgern das es m¨ oglich war SPhPs mit beiden Gittersystemen anzuregen. Weiterhin zeigten die Messergebnisse gute ¨ Ubereinstimmung mit den Simulationensergebnissen. Im Falle des Goldgitters zeigte sich das Ausbilden einer hybriden SPP-SPhP Mode welche Gegenstand neuer Unter- suchungen werden k¨ onnte. Diese Arbeit vermittelt somit ein grundlegendes Verst¨ andnis ¨ uber den Einfluss der verschiedenen Gitterparameter auf die Kopplungseffizienz, zeigt das SPhP Anregung in der SiC-Oberfl¨ ache auch mit anderen Gittermaterialien m¨ oglich ist und erm¨ oglicht somit die Entwicklung neuartiger Gittersysteme die sich hybride SPP-SPhP Moden zunutze machen

A note on multi-dimensional Camassa-Holm type systems on the torus

We present a $2n$-component nonlinear evolutionary PDE which includes the $n$-dimensional versions of the Camassa-Holm and the Hunter-Saxton systems as well as their partially averaged variations. Our goal is to apply Arnold's [V.I. Arnold, Sur la g\'eom\'etrie diff\'erentielle des groupes de Lie de dimension infinie et ses applications \`a l'hydrodynamique des fluides parfaits. Ann. Inst. Fourier (Grenoble) 16 (1966) 319-361], [D.G. Ebin and J.E. Marsden, Groups of diffeomorphisms and the motion of an incompressible fluid. Ann. of Math. 92(2) (1970) 102-163] geometric formalism to this general equation in order to obtain results on well-posedness, conservation laws or stability of its solutions. Following the line of arguments of the paper [M. Kohlmann, The two-dimensional periodic $b$-equation on the diffeomorphism group of the torus. J. Phys. A.: Math. Theor. 44 (2011) 465205 (17 pp.)] we present geometric aspects of a two-dimensional periodic $\mu$-$b$-equation on the diffeomorphism group of the torus in this context.Comment: 14 page

The geometry of the two-component Camassa-Holm and Degasperis-Procesi equations

We use geometric methods to study two natural two-component generalizations of the periodic Camassa-Holm and Degasperis-Procesi equations. We show that these generalizations can be regarded as geodesic equations on the semidirect product of the diffeomorphism group of the circle \Diff(S^1) with some space of sufficiently smooth functions on the circle. Our goals are to understand the geometric properties of these two-component systems and to prove local well-posedness in various function spaces. Furthermore, we perform some explicit curvature calculations for the two-component Camassa-Holm equation, giving explicit examples of large subspaces of positive curvature.Comment: 31 page

The validity and internal structure of the bipolar depression rating scale (BDRS): data from a clinical trial of N-acetylcysteine as adjunctive therapy in bipolar disorder

Background: The phenomenology of unipolar and bipolar disorders differ in a number of ways, such as the presence of mixed states and atypical features. Conventional depression rating instruments are designed to capture the characteristics of unipolar depression and have limitations in capturing the breadth of bipolar disorder.Method: The Bipolar Depression Rating Scale (BDRS) was administered together with the Montgomery Asberg Rating Scale (MADRS) and Young Mania Rating Scale (YMRS) in a double-blind randomised placebo-controlled clinical trial of N-acetyl cysteine for bipolar disorder (N = 75).Results: A factor analysis showed a two-factor solution: depression and mixed symptom clusters. The BDRS has strong internal consistency (Cronbach\u27s alpha = 0.917), the depression cluster showed robust correlation with the MADRS (r = 0.865) and the mixed subscale correlated with the YMRS (r = 0.750).Conclusion: The BDRS has good internal validity and inter-rater reliability and is sensitive to change in the context of a clinical trial.<br /

Second Harmonic Generation from Grating-Coupled Hybrid Plasmon-Phonon Polaritons

Polaritons can provide strong optical field enhancement allowing to boost light-matter interaction. Here, we experimentally observe enhancement of mid-infrared second-harmonic generation (SHG) using grating-coupled surface phonon polaritons of the 6H-SiC surface. In our experiment, we measure the SHG along the polariton dispersion by changing the incidence angle of the excitation beam. We observe hybridization between the propagating surface phonon polaritons and localized plasmon resonances in the gold grating, evidenced by the modification of the polariton dispersion as we change the area ratio of grating and substrate. Design options for engineering the plasmon-phonon polariton hybridization are discussed. Overall, we find a rather low yield of polariton-enhanced SHG in this geometry compared to prism-coupling and nanostructures, and discuss possible origins

Magnetization reversal of an individual exchange biased permalloy nanotube

We investigate the magnetization reversal mechanism in an individual permalloy (Py) nanotube (NT) using a hybrid magnetometer consisting of a nanometer-scale SQUID (nanoSQUID) and a cantilever torque sensor. The Py NT is affixed to the tip of a Si cantilever and positioned in order to optimally couple its stray flux into a Nb nanoSQUID. We are thus able to measure both the NT's volume magnetization by dynamic cantilever magnetometry and its stray flux using the nanoSQUID. We observe a training effect and temperature dependence in the magnetic hysteresis, suggesting an exchange bias. We find a low blocking temperature $T_B = 18 \pm 2$ K, indicating the presence of a thin antiferromagnetic native oxide, as confirmed by X-ray absorption spectroscopy on similar samples. Furthermore, we measure changes in the shape of the magnetic hysteresis as a function of temperature and increased training. These observations show that the presence of a thin exchange-coupled native oxide modifies the magnetization reversal process at low temperatures. Complementary information obtained via cantilever and nanoSQUID magnetometry allows us to conclude that, in the absence of exchange coupling, this reversal process is nucleated at the NT's ends and propagates along its length as predicted by theory.Comment: 8 pages, 4 figure