Sartoryglabrins, analogs of ardeemins, from Neosartorya glabra

Chemical investigation of a collection of the fungus Neosartorya glabra from Thailand furnished sartoryglabins A-C (1a, 1b and 2) which are analogs of the reverse prenylated indole alkaloids known as (-) ardeemins. Structures of these compounds were established by NMR spectrometry and an X-ray analysis. Sartoryglabins A-C were evaluated for their in vitro growth inhibitory activity on three human tumor cell lines: MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer) and A375-C5 (melanoma). All the compounds exhibited strong to moderate activity against the MCF-7 cell line but weak or no activity against the NCI-H460 and A375-C5 cell lines. Sartoryglabin B was found to exhibit selectivity towards the MCF-7 cell line.     

Directing energy transfer in discrete one-dimensional oligonucleotide-templated assemblies

Monodisperse DNA-templated one dimensional dye assemblies have been constructed in which the energy transfer can be directed. Fluorescence experiments suggest an optimum transfer efficiency for stacks of 30 bases long.     

The string landscape: On formulas for counting vacua

We derive formulas for counting certain classes of vacua in the string/M theory landscape. We do so in the context of the moduli space of M-theory compactifications on singular manifolds with _G2$G_2$ holonomy. Particularly, we count the numbers of gauge theories with different gauge groups but equal numbers of U(1)$U(1)$ factors which are dual to each other. The vacua correspond to various symmetry breaking patterns of grand unified theories. Counting these dual vacua is equivalent to counting the number of conjugacy classes of elements of finite order inside Lie groups. We also point out certain cases where the conventional expectation is that symmetry breaking patterns by Wilson lines and Higgs fields are the same, but we show they are in fact different.     

High-Pressure/High-Temperature NFS Study of Magnetism in LuFe 2 and ScFe 2

Using the new technique of nuclear forward scattering (NFS) of synchrotron radiation, we studied the magnetic hyperfine fields B hf and ordering temperatures T M of the Laves phases LuFe 2 (cubic C15) and ScFe 2 (hexagonal C14) at pressures up to 90 GPa and temperatures up to 700 K. For LuFe 2 we find for T M first an increase from 562 K at 0 GPa to 603 K at 10 GPa and then a decrease to 295 K around 75 GPa. The hyperfine fields B hf show at 295 K a continuous decrease with pressure, indicating a reduction of the Fe band moment. A similar behaviour of both T M and B hf was observed in ScFe 2.     

A modular and efficient approach to computational modeling and sensitivity analysis of robot and human motion dynamics

In this paper a new class library for the computation of the forward multi-body-system (MBS) dynamics of robots and biomechanical models of human motion is presented. By the developed modular modeling approach the library can be flexibly extended by specific modeling elements like joints with specific geometry or different muscle models and thus can be applied efficiently for a number of dynamic simulation and optimization problems. The library not only provides several methods for solving the forward dynamics problem (like articulated body or composite rigid body algorithms) which can transparently be exchanged. Moreover, the numerical solution of optimal control problems, like in the forward dynamics optimization of human motion, is significantly facilitated by the computation of the sensitivity matrix with respect to the control variables. Examples are given to demonstrate the efficiency of the approach. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

H p -spaces of martingales, 0<p≦1

For 0 <p≦1 the dual Banach space to the space of H _p -martingales is characterized as a Lipschitz class of order α=l/p?1. When p=1 and α=0 this reduces to BMO being the dual of H ₁ . In the course of the investigation a hierarchy of martingale spaces _a L _p is introduced with the property that the index p is in the range ?∞ <1/p<∞. For l≦b≦q<∞ the space L _q is a subspace of _b L _q (equality when b=q) while for q<0 the space _b L _q corresponds to a Lipschitz class of order α=?1/q.