3,624 research outputs found
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Evolution of substrate-specific gene expression and RNA editing in brown rot wood-decaying fungi.
Fungi that decay wood have characteristic associations with certain tree species, but the mechanistic bases for these associations are poorly understood. We studied substrate-specific gene expression and RNA editing in six species of wood-decaying fungi from the 'Antrodia clade' (Polyporales, Agaricomycetes) on three different wood substrates (pine, spruce, and aspen) in submerged cultures. We identified dozens to hundreds of substrate-biased genes (i.e., genes that are significantly upregulated in one substrate relative to the other two substrates) in each species, and these biased genes are correlated with their host ranges. Evolution of substrate-biased genes is associated with gene family expansion, gain and loss of genes, and variation in cis- and trans- regulatory elements, rather than changes in protein coding sequences. We also demonstrated widespread RNA editing events in the Antrodia clade, which differ from those observed in the Ascomycota in their distribution, substitution types, and the genomic environment. Moreover, we found that substrates could affect editing positions and frequency, including editing events occurring in mRNA transcribed from wood-decay-related genes. This work shows the extent to which gene expression and RNA editing differ among species and substrates, and provides clues into mechanisms by which wood-decaying fungi may adapt to different hosts
Collapse of the vortex-lattice inductance and shear modulus at the melting transition in untwinned
The complex resistivity of the vortex lattice in an
untwinned crystal of 93-K has been measured at frequencies
from 100 kHz to 20 MHz in a 2-Tesla field ,
using a 4-probe RF transmission technique that enables continuous measurements
versus and temperature . As is increased, the inductance increases steeply to a cusp
at the melting temperature , and then undergoes a steep collapse
consistent with vanishing of the shear modulus . We discuss in detail
the separation of the vortex-lattice inductance from the `volume' inductance,
and other skin-depth effects. To analyze the spectra, we consider a weakly
disordered lattice with a low pin density. Close fits are obtained to
over 2 decades in . Values of the pinning parameter
and shear modulus obtained show that collapses by
over 4 decades at , whereas remains finite.Comment: 11 pages, 8 figures, Phys. Rev. B, in pres
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Intimate partner violence and substance abuse among minority women receiving care from an inner-city emergency department
Objective. The study describes the rates of lifetime and current IPV among women awaiting care in an emergency department and explores the association between IPV and having a drug abuse problem, and IPV and having an alcohol abuse problem, after controlling for demographic factors and history of childhood victimization.
Methods. Face-to-face interviews were conducted with 143 low-level triaged women recruited from an inner-city emergency department.
Results. Nearly one-half reported ever experiencing IPV, and over 18% reported IPV during the year before the interview. A higher proportion of abused women reported a history of regular crack, cocaine, or heroin use and visiting shooting galleries or crack houses. Participants who were physically abused by their partner during the past year (15%, n = 21) were more likely than nonabused women (85%, n = 122) to report higher scores on the Alcohol Use Disorders Identification Test (AUDIT) (4.9 vs. 2.4), a measure of alcohol-related problems, and the Drug Abuse Severity Test (DAST) (3.0 vs. 1.3), a measure of drug-related problems. Sexually abused women (6%, n = 9) were more likely than their counterparts (94%, n = 134) to have significantly higher AUDIT scores (6.4 vs. 2.5). The findings have implications for how the intersecting public health problems of IPV and substance abuse should be taken into consideration in research and patient care protocols in emergency departments
Chaotic Repellers in Antiferromagnetic Ising Model
For the first time we present the consideration of the antiferromagnetic
Ising model in case of fully developed chaos and obtain the exact connection
between this model and chaotic repellers. We describe the chaotic properties of
this statistical mechanical system via the invariants characterizing a fractal
set and show that in chaotic region it displays phase transition at {\it
positive} "temperature" . We obtain the density of the
invariant measure on the chaotic repeller.Comment: LaTeX file, 10 pages, 4 PS figurs upon reques
K-matrices for 2D conformal field theories
In this paper we examine fermionic type characters (Universal Chiral
Partition Functions) for general 2D conformal field theories with a bilinear
form given by a matrix of the form K \oplus K^{-1}. We provide various
techniques for determining these K-matrices, and apply these to a variety of
examples including (higher level) WZW and coset conformal field theories.
Applications of our results to fractional quantum Hall systems and (level
restricted) Kostka polynomials are discussed.Comment: 59 pages, 2 figures, v2: note added, minor changes, references added,
v3: typos correcte
Exclusion statistics in conformal field theory and the UCPF for WZW models
In this paper we further elaborate on the notion of fractional exclusion
statistics, as introduced by Haldane, in two-dimensional conformal field
theory, and its connection to the Universal Chiral Partition Function as
defined by McCoy and collaborators. We will argue that in general, besides the
pseudo-particles introduced recently by Guruswamy and Schoutens, one needs
additional `null quasi-particles' to account for the null-states in the
quasi-particle Fock space. We illustrate this in several examples of
WZW-models.Comment: plain TeX, 31 pages; ref adde
Quantum Nonlinear Switching Model
We present a method, the dynamical cumulant expansion, that allows to
calculate quantum corrections for time-dependent quantities of interacting spin
systems or single spins with anisotropy. This method is applied to the
quantum-spin model \hat{H} = -H_z(t)S_z + V(\bf{S}) with H_z(\pm\infty) =
\pm\infty and \Psi (-\infty)=|-S> we study the quantity P(t)=(1-_t/S)/2.
The case V(\bf{S})=-H_x S_x corresponds to the standard
Landau-Zener-Stueckelberg model of tunneling at avoided-level crossing for N=2S
independent particles mapped onto a single-spin-S problem, P(t) being the
staying probability. Here the solution does not depend on S and follows, e.g.,
from the classical Landau-Lifshitz equation. A term -DS_z^2 accounts for
particles' interaction and it makes the model nonlinear and essentially quantum
mechanical. The 1/S corrections obtained with our method are in a good accord
with a full quantum-mechanical solution if the classical motion is regular, as
for D>0.Comment: 4 Phys. Rev. pages 2 Fig
Dichloroacetate and PX-478 exhibit strong synergistic effects in a various number of cancer cell lines
Background: One key approach for anticancer therapy is drug combination. Drug combinations can help reduce doses and thereby decrease side effects. Furthermore, the likelihood of drug resistance is reduced. Distinct alterations in tumor metabolism have been described in past decades, but metabolism has yet to be targeted in clinical cancer therapy. Recently, we found evidence for synergism between dichloroacetate (DCA), a pyruvate dehydrogenase kinase inhibitor, and the HIF-1 alpha inhibitor PX-478. In this study, we aimed to analyse this synergism in cell lines of different cancer types and to identify the underlying biochemical mechanisms.
Methods: The dose-dependent antiproliferative effects of the single drugs and their combination were assessed using SRB assays. FACS, Western blot and HPLC analyses were performed to investigate changes in reactive oxygen species levels, apoptosis and the cell cycle. Additionally, real-time metabolic analyses (Seahorse) were performed with DCA-treated MCF-7 cells.
Results: The combination of DCA and PX-478 produced synergistic effects in all eight cancer cell lines tested, including colorectal, lung, breast, cervical, liver and brain cancer. Reactive oxygen species generation and apoptosis played important roles in this synergism. Furthermore, cell proliferation was inhibited by the combination treatment.
Conclusions: Here, we found that these tumor metabolism-targeting compounds exhibited a potent synergism across all tested cancer cell lines. Thus, we highly recommend the combination of these two compounds for progression to in vivo translational and clinical trials
Exclusion Statistics in Conformal Field Theory -- generalized fermions and spinons for level-1 WZW theories
We systematically study the exclusion statistics for quasi-particles for
Conformal Field Theory spectra by employing a method based on recursion
relations for truncated spectra. Our examples include generalized fermions in
c<1 unitary minimal models, Z_k parafermions, and spinons for the su(n)_1,
so(n)_1 and sp(2n)_1 Wess-Zumino-Witten models. For some of the latter examples
we present explicit expressions for finitized affine characters and for the
N-spinon decomposition of affine characters.Comment: LaTeX, 49 pages, some further clarifications added, refs added and
updated. Nucl. Phys. B, to be publishe
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