Investigation of effects of essential oils of Origanum minutiflorum O Schwarz PH Davis and Cyclotrichium niveum (Labiatae) plants on angiogenesis in shell-less chick embryo culture

The aim of this study was to investigate the effect of essential oils extracted from Origanum minutiflorum and Cyclotrichium niveum (Labiatae) plants to the vascularization systems of the chick embryos in a chorioallantoic membrane model. The aerial parts of O. minutiflorum and C. niveum were subjected to hydrodistillation. Essential oils were applied to the center of the blastodisc of 50 μl using a precision micropipette prior to the transfer of shell-less cultures to the incubator. Antiangiogenic effect of essential oil of the study plants was determined with the use of chorioallantoic membrane model. Numbers of main, branching and capillary blood vessels were counted. In the statistical analysis, when the groups were compared with regard to the main blood vessel (MBV) and branch blood vessel (BBV) development, no significant difference (p > 0.05) was observed. However, when the groups were compared with regard to capillary vessel (CV) development, the difference between the data of the groups was found significant (p < 0.05). One of the tested compounds, C. niveum essential oils, showed antiangiogenic effect; while the other, O. minutiflorum showed no antiangiogenic effect. This study examined the effect of exposure to O. minutiflorum and C. niveum essential oils on extraembryonic vascular development in the chick embryo area vasculosa (AV) in shell-less culture for the first time. Essential oils extracted from C. niveum has antiangiogenic effect; while O. minutiflorum essential oils had no antiangiogenic effect

On Some Geometric Structures Associated to a k-Symplectic Manifold

A canonical connection is attached to any k-symplectic manifold. We study the properties of this connection and its geometric applications to k-symplectic manifolds. In particular we prove that, under some natural assumption, any ksymplectic manifold admits an Ehresmann connection, discussing some corollaries of this result, and we find vanishing theorems for characteristic classes on a k-symplectic manifold.Comment: To appear on J. Phys. A: Math. Theo

Some Results on Cubic and Higher Order Extensions of the Poincar\'e Algebra

In these lectures we study some possible higher order (of degree greater than two) extensions of the Poincar\'e algebra. We first give some general properties of Lie superalgebras with some emphasis on the supersymmetric extension of the Poincar\'e algebra or Supersymmetry. Some general features on the so-called Wess-Zumino model (the simplest field theory invariant under Supersymmetry) are then given. We further introduce an additional algebraic structure called Lie algebras of order F, which naturally comprise the concepts of ordinary Lie algebras and superalgebras. This structure enables us to define various non-trivial extensions of the Poincar\'e algebra. These extensions are studied more precisely in two different contexts. The first algebra we are considering is shown to be an (infinite dimensional) higher order extension of the Poincar\'e algebra in $(1+2)-$dimensions and turns out to induce a symmetry which connects relativistic anyons. The second extension we are studying is related to a specific finite dimensional Lie algebra of order three, which is a cubic extension of the Poincar\'e algebra in $D-$space-time dimensions. Invariant Lagrangians are constructed.Comment: Mini course given at the Workshop higher symmetries in physics, Madrid, Spain, November 6-8, 200

Electromagnetic Properties of Inner Double Walled Carbon Nanotubes Investigated by Nuclear Magnetic Resonance

The nuclear magnetic resonance (NMR) analytical technique was used to investigate the double walled carbon nanotubes (DWNTs) electromagnetic properties of inner walls. The local magnetic and electronic properties of inner nanotubes in DWNTs were analyzed using 25% 13C enriched C60 by which the effect of dipolar coupling could be minimized. The diamagnetic shielding was determined due to the ring currents on outer nanotubes in DWNTs. The NMR chemical shift anisotropy (CSA) spectra and spin-lattice relaxation studies reveal the metallic properties of the inner nanotubes with a signature of the spin-gap opening below 70 K