16 research outputs found
Persistence length of semiflexible polymers and bending rigidity renormalization
The persistence length of semiflexible polymers and one-dimensional fluid
membranes is obtained from the renormalization of their bending rigidity. The
renormalized bending rigidity is calculated using an exact real-space
functional renormalization group transformation based on a mapping to the
one-dimensional Heisenberg model. The renormalized bending rigidity vanishes
exponentially at large length scales and its asymptotic behaviour is used to
define the persistence length. For semiflexible polymers, our result agrees
with the persistence length obtained using the asymptotic behaviour of tangent
correlation functions. Our definition differs from the one commonly used for
fluid membranes, which is based on a perturbative renormalization of the
bending rigidity.Comment: 7 page
Persistence length of semiflexible polymers and bending rigidity renormalization
The persistence length of semiflexible polymers and one-dimensional fluid
membranes is obtained from the renormalization of their bending rigidity. The
renormalized bending rigidity is calculated using an exact real-space
functional renormalization group transformation based on a mapping to the
one-dimensional Heisenberg model. The renormalized bending rigidity vanishes
exponentially at large length scales and its asymptotic behaviour is used to
define the persistence length. For semiflexible polymers, our result agrees
with the persistence length obtained using the asymptotic behaviour of tangent
correlation functions. Our definition differs from the one commonly used for
fluid membranes, which is based on a perturbative renormalization of the
bending rigidity.Comment: 7 page
Decay widths of three-impurity states in the BMN correspondence
We extend the study of the quantum mechanics of BMN gauge theory to the
sector of three scalar impurities at one loop and all genus. The relevant
matrix elements of the non-planar one loop dilatation operator are computed in
the gauge theory basis. After a similarity transform the BMN gauge theory
prediction for the corresponding piece of the plane wave string Hamiltonian is
derived and shown to agree with light-cone string field theory. In the
three-impurity sector single string states are unstable for the decay into
two-string states at leading order in g_2. The corresponding decay widths are
computed.Comment: 30 pages, 3 figures. v2: references adde
New aspects of the BMN correspondence beyond the planar limit
Motivated by recent disagreements in the context of AdS/CFT, we study the
non-planar sector of the BMN correspondence. In particular, we reconsider the
energy shift of states with two stringy excitations in light-cone string field
theory and explicitly determine its complete perturbative contribution from the
impurity-conserving channel. Surprisingly, our result neither agrees with
earlier leading order computations, nor reproduces the gauge theory prediction.
More than that, it features half-integer powers of the effective gauge coupling
representing a qualitative difference to gauge theory. Based on
supersymmetry we argue that the above truncation is not suited for conclusive
tests of the BMN duality.Comment: 20 pages, 1 figur
A global Staphylococcus aureus proteome resource applied to the in vivo characterization of host-pathogen interactions.
Data-independent acquisition mass spectrometry promises higher performance in terms of quantification and reproducibility compared to data-dependent acquisition mass spectrometry methods. To enable high-accuracy quantification of Staphylococcus aureus proteins, we have developed a global ion library for data-independent acquisition approaches employing high-resolution time of flight or Orbitrap instruments for this human pathogen. We applied this ion library resource to investigate the time-resolved adaptation of S. aureus to the intracellular niche in human bronchial epithelial cells and in a murine pneumonia model. In epithelial cells, abundance changes for more than 400 S. aureus proteins were quantified, revealing, e.g., the precise temporal regulation of the SigB-dependent stress response and differential regulation of translation, fermentation, and amino acid biosynthesis. Using an in vivo murine pneumonia model, our data-independent acquisition quantification analysis revealed for the first time the in vivo proteome adaptation of S. aureus. From approximately 2.15 × 1
Record 13% efficiency screen printed silicon solar cells on ribbon growth on substrate (RGS) material
Direct casting of silicon into wafers allows to produce wafers much more cheaply than in traditional block casting methods. RGS (Ribbon Growth on Substrate) is such a method. In order for RGS to be cost effective sufficient cell efficiencies must be realized. In this paper we present 13.0% efficient screen printed RGS cells. This is an increase of 0.6% absolute compared to the best previous result reported in January 2005. The increase was achieved by reducing shunting in cells made on RGS material. The cells have been made both with alkaline etching of the wafer and with iso texturing.publishe