Well-preserved holdfasts and early growth stages of the tubular cnidarian Sphenothallus are described from Silurian (Llandovery Series) Washington Land, North Greenland. The diameter holdfast is determined by formation a basal disc attached to substrate, upon which initially conical, but subsequently shell formed. characteristic opposing longitudinal thickenings developed at each angular margin...

The Space industry demand for lighter and cheaper launcher transport systems. The upcoming EU project DESICOS (New Robust DESIgn Guideline for Imperfection Sensitive COmposite Launcher Structures), which will start in 2012, contributes to these aims by a new design procedure for imperfection sensitive composite launcher structures, exploiting the worst imperfection approach efficiently by imple...

We review on a recent construction of the on-shell supersymmetric brane action for the codimension-two branes with nonzero tension in the flux compactification of a 6D chiral gauged supergravity. On dimesionally reducing on 4D gauged supergravity for a new supersymmetric unwarped background with conical branes, we consider the modulus stabilization for determining the soft masses of the scalars...

A method for numerically solving the equation of radiative transfer in a spherical shell atmosphere is presented. The method uses a conical boundary and a Gauss-Seidel iteration scheme to solve for all orders of scattering along a single radial line in the atmosphere. Tests of the model indicate an accuracy better than 1% for most Earth-atmosphere situations. Results from this model are compare...

Consider a spherically symmetric spacelike slice through a spherically symmetric spacetime. One can derive a universal bound for the optical scalars on any such slice. The only requirement is that the matter sources satisfy the dominant energy condition and that the slice be asymptotically flat and regular at the origin. This bound can be used to derive new conditions for the formation of appar...

The confinement of double stranded (ds) viral DNA molecules has long attracted the interest of physicists. The bacteriophage viruses are the classical example of viruses where large pressures are produced by viral DNA confinement (in the range of tens of atmospheres)[1]. The protein shell the capsid has to be very strong so as to withstand these enormous pressures. In this article we propose th...

As a major structural dynamic criterion in designing thin shells, the fundamental frequency is maximized for a specified total structural mass. The general optimization problem of metallic conical shell structures with clamped / free ends has been treated formally among all other types of boundary conditions. Both stiffened and unstiffened constructions are examined with the effective design va...

Rice dwarf virus (RDV), a member of the Reoviridae family, is a double-stranded RNA virus. Infection of rice plants with RDV reduces crop production significantly and can pose a major economic threat to Southeast Asia. A 25-A three-dimensional structure of the 700-A-diameter RDV capsid has been determined by 400-kV electron cryomicroscopy and computer reconstruction. The structure revealed two ...