title:
Variance function estimation in quantitative mass spectrometry with
  application to iTRAQ labeling

abstract:
  This paper describes and compares two methods for estimating the variance
function associated with iTRAQ (isobaric tag for relative and absolute
quantitation) isotopic labeling in quantitative mass spectrometry based
proteomics. Measurements generated by the mass spectrometer are proportional to
the concentration of peptides present in the biological sample. However, the
iTRAQ reporter signals are subject to errors that depend on the peptide
amounts. The variance function of the errors is therefore an essential
parameter for evaluating the results, but estimating it is complicated, as the
number of nuisance parameters increases with sample size while the number of
replicates for each peptide remains small. Two experiments that were conducted
with the sole goal of estimating the variance function and its stability over
time are analyzed, and the resulting estimated variance function is used to
analyze an experiment targeting aberrant signaling cascades in cells harboring
distinct oncogenic mutations. Methods for constructing conservative $p$-values
and confidence intervals are discussed.


title:
Weighted Estimates for Multilinear Commutators of Marcinkiewicz
  Integrals with Bounded Kernel

abstract:
  Let $\mu_{\Omega,\vec{b}}$ be the multilinear commutator generalized by
$\mu_{\Omega}$, the $n$-dimensional Marcinkiewicz integral with the bounded
kernel, and $b_{j}\in \Osc_{\exp L^{r_{j}}}(1\le j\le m)$. In this paper, the
following weighted inequalities are proved for $\omega\in A_{\infty}$ and
$0<p<\infty$,
  $$\|\mu_{\Omega}(f)\|_{L^{p}(\omega)}\leq C\|M(f)\|_{L^{p}(\omega)}, \ \
\|\mu_{\Omega,\vec{b}}(f)\|_{L^{p}(\omega)}\leq C\|M_{L(\log
L)^{1/r}}(f)\|_{L^{p}(\omega)}.$$
  The weighted weak $L(\log L)^{1/r}$ -type estimate is also established when
$p=1$ and $\omega\in A_{1}$.


title: Magnetically Active Stars in Taurus-Auriga: Evolutionary Status

abstract:
  We have analyzed a sample of 74 magnetically active stars toward the
Taurus-Auriga star-forming region. Based on accurate data on their basic
physical parameters obtained from original photometric observations and
published data on their proper motions, X-ray luminosities, and equivalent
widths of the $\rm H\alpha$ and Li lines, we have refined the evolutionary
status of these objects. We show that 50 objects are young stars with ages of
1-40 Myr and belong to the Taurus-Auriga star-forming region. Other 20 objects
have a controversial evolutionary status and can belong to both Taurus-Auriga
star-forming region and the Gould Belt. The remaining four objects with ages of
70-100 Myr belong to the zero-age main sequence. We have analyzed the
relationship between the rotation period, mass, and age for 50 magnetically
active stars. The change in the angular momentum of the sample stars within the
first 40 Myr of their evolution has been investigated. An active
star-protoplanetary disk interaction is shown to occur on a time scale from 0.7
to 10 Myr.


title: Bayesian Model Selection for LISA Pathfinder

abstract:
  The main goal of the LISA Pathfinder (LPF) mission is to fully characterize
the acceleration noise models and to test key technologies for future
space-based gravitational-wave observatories similar to the eLISA concept. The
data analysis team has developed complex three-dimensional models of the LISA
Technology Package (LTP) experiment on-board LPF. These models are used for
simulations, but more importantly, they will be used for parameter estimation
purposes during flight operations. One of the tasks of the data analysis team
is to identify the physical effects that contribute significantly to the
properties of the instrument noise. A way of approaching this problem is to
recover the essential parameters of a LTP model fitting the data. Thus, we want
to define the simplest model that efficiently explains the observations. To do
so, adopting a Bayesian framework, one has to estimate the so-called Bayes
Factor between two competing models. In our analysis, we use three main
different methods to estimate it: The Reversible Jump Markov Chain Monte Carlo
method, the Schwarz criterion, and the Laplace approximation. They are applied
to simulated LPF experiments where the most probable LTP model that explains
the observations is recovered. The same type of analysis presented in this
paper is expected to be followed during flight operations. Moreover, the
correlation of the output of the aforementioned methods with the design of the
experiment is explored.


title: Mesons in large-N QCD

abstract:
  We present the results of a systematic, first-principles study of the
spectrum and decay constants of mesons for different numbers of color charges
N, via lattice computations. We restrict our attention to states in the
non-zero isospin sector, evaluating the masses associated with the ground-state
and first excitation in the pseudoscalar, vector, scalar, and axial vector
channels. Our results are based on a new set of simulations of four dimensional
SU(N) Yang-Mills theories with the number of colors ranging from N=2 to N=17;
the spectra and the decay constants are computed in the quenched approximation
(which becomes exact in the 't Hooft limit) using Wilson fermions. After
discussing the extrapolations to the chiral and large-N limits, we present a
comparison of our results to some of the numerical computations and analytical
predictions available in the literature - including, in particular, those from
holographic computations.


title: How entropy and hydrodynamics cooperate in rectifying particle transport

abstract:
  Using the analytical Fick-Jacobs approximation formalism and extensive
Brownian dynamics simulations we study particle transport through
two-dimensional periodic channels with triangularly shaped walls. Directed
motion is caused by the interplay of constant bias acting along the channel
axis and a pressure-driven flow. In particular, we analyze the particle
mobility and the effective diffusion coefficient. The mechanisms of entropic
rectification is revealed in channels with a broken spatial reflection symmetry
in presence of hydrodynamically enforced entropic trapping. Due to the combined
action of the forcing and the pressure-driven flow field, efficient
rectification with a drastically reduced diffusivity is achieved.


title:
Varying coefficient model for modeling diffusion tensors along white
  matter tracts

abstract:
  Diffusion tensor imaging provides important information on tissue structure
and orientation of fiber tracts in brain white matter in vivo. It results in
diffusion tensors, which are $3\times3$ symmetric positive definite (SPD)
matrices, along fiber bundles. This paper develops a functional data analysis
framework to model diffusion tensors along fiber tracts as functional data in a
Riemannian manifold with a set of covariates of interest, such as age and
gender. We propose a statistical model with varying coefficient functions to
characterize the dynamic association between functional SPD matrix-valued
responses and covariates. We calculate weighted least squares estimators of the
varying coefficient functions for the log-Euclidean metric in the space of SPD
matrices. We also develop a global test statistic to test specific hypotheses
about these coefficient functions and construct their simultaneous confidence
bands. Simulated data are further used to examine the finite sample performance
of the estimated varying coefficient functions. We apply our model to study
potential gender differences and find a statistically significant aspect of the
development of diffusion tensors along the right internal capsule tract in a
clinical study of neurodevelopment.


title: 2- and 3-modular Lattice Wiretap Codes in Small Dimensions

abstract:
  A recent line of work on lattice codes for Gaussian wiretap channels
introduced a new lattice invariant called secrecy gain as a code design
criterion which captures the confusion that lattice coding produces at an
eavesdropper. Following up the study of unimodular lattice wiretap codes [1],
this paper investigates 2- and 3-modular lattices and compares them with
unimodular lattices. Most even 2- and 3-modular lattices are found to have
better performance, that is, a higher secrecy gain than the best unimodular
lattices in dimension n, n is between 2 and 23. Odd 2-modular lattices are
considered, too, and three lattices are found to outperform the best unimodular
lattices.


title: Bayesian analysis of dynamic item response models in educational testing

abstract:
  Item response theory (IRT) models have been widely used in educational
measurement testing. When there are repeated observations available for
individuals through time, a dynamic structure for the latent trait of ability
needs to be incorporated into the model, to accommodate changes in ability.
Other complications that often arise in such settings include a violation of
the common assumption that test results are conditionally independent, given
ability and item difficulty, and that test item difficulties may be partially
specified, but subject to uncertainty. Focusing on time series dichotomous
response data, a new class of state space models, called Dynamic Item Response
(DIR) models, is proposed. The models can be applied either retrospectively to
the full data or on-line, in cases where real-time prediction is needed. The
models are studied through simulated examples and applied to a large collection
of reading test data obtained from MetaMetrics, Inc.


title:
Resonant THz sensor for paper quality monitoring using THz fiber Bragg
  gratings

abstract:
  We report fabrication of THz fiber Bragg gratings (TFBG) using CO2 laser
inscription on subwavelength step-index polymer fibers. A fiber Bragg grating
with 48 periods features a ~4 GHz-wide stop band and ~15 dB transmission loss
in the middle of a stop band. The potential of such gratings in design of
resonant sensor for monitoring of paper quality is demonstrated. Experimental
spectral sensitivity of the TFBG-based paper thickness sensor was found to be ~
-0.67 GHz / 10 um. A 3D electromagnetic model of a Bragg grating was used to
explain experimental findings.


title: Light-cone Wilson loop in classical lattice gauge theory

abstract:
  The transverse broadening of an energetic jet passing through a non-Abelian
plasma is believed to be described by the thermal expectation value of a
light-cone Wilson loop. In this exploratory study, we measure the light-cone
Wilson loop with classical lattice gauge theory simulations. We observe, as
suggested by previous studies, that there are strong interactions already at
short transverse distances, which may lead to more efficient jet quenching than
in leading-order perturbation theory. We also verify that the asymptotics of
the Wilson loop do not change qualitatively when crossing the light cone, which
supports arguments in the literature that infrared contributions to jet
quenching can be studied with dimensionally reduced simulations in the
space-like domain. Finally we speculate on possibilities for full
four-dimensional lattice studies of the same observable, perhaps by employing
shifted boundary conditions in order to simulate ensembles boosted by an
imaginary velocity.


title:
Nanointerferometric Amplitude and Phase Reconstruction of Tightly
  Focused Vector Beams

abstract:
  Highly confined vectorial electromagnetic field distributions represent an
excellent tool for detailed studies in nano-optics and high resolution
microscopy, such as nonlinear microscopy, advanced fluorescence imaging or
nanoplasmonics. Such field distributions can be generated, for instance, by
tight focussing of polarized light beams. To guarantee high quality and
resolution in the investigation of objects with sub-wavelength dimensions, the
precise knowledge of the spatial distribution of the exciting vectorial field
is of utmost importance. Full-field reconstruction methods presented so far
involved, for instance, complex near-field techniques. Here, we demonstrate a
simple and straight-forward to implement measurement scheme and reconstruction
algorithm based on the scattering signal of a single spherical nanoparticle as
a field-probe. We are able to reconstruct the amplitudes of the individual
focal field components as well as their relative phase distributions with
sub-wavelength resolution from a single scan measurement without the need for
polarization analysis of the scattered light. This scheme can help to improve
modern microscopy and nanoscopy techniques.


title:
Modeling temporal gradients in regionally aggregated California asthma
  hospitalization data

abstract:
  Advances in Geographical Information Systems (GIS) have led to the enormous
recent burgeoning of spatial-temporal databases and associated statistical
modeling. Here we depart from the rather rich literature in space-time modeling
by considering the setting where space is discrete (e.g., aggregated data over
regions), but time is continuous. Our major objective in this application is to
carry out inference on gradients of a temporal process in our data set of
monthly county level asthma hospitalization rates in the state of California,
while at the same time accounting for spatial similarities of the temporal
process across neighboring counties. Use of continuous time models here allows
inference at a finer resolution than at which the data are sampled. Rather than
use parametric forms to model time, we opt for a more flexible stochastic
process embedded within a dynamic Markov random field framework. Through the
matrix-valued covariance function we can ensure that the temporal process
realizations are mean square differentiable, and may thus carry out inference
on temporal gradients in a posterior predictive fashion. We use this approach
to evaluate temporal gradients where we are concerned with temporal changes in
the residual and fitted rate curves after accounting for seasonality,
spatiotemporal ozone levels and several spatially-resolved important
sociodemographic covariates.


title: What have we learned from observational cosmology ?

abstract:
  We review the observational foundations of the $\Lambda$CDM model, considered
by most cosmologists as the standard model of cosmology. The Cosmological
Principle, a key assumption of the model is shown to be verified with
increasing accuracy. The fact that the Universe seems to have expanded from and
hot and dense past is supported by many independent probes (galaxy redshifts,
Cosmic Microwave Background, Big-Bang Nucleosynthesis and reionization). The
explosion of detailed observations in the last few decades has allowed for
precise measurements of the cosmological parameters within
Friedman-Lema\^itre-Robertson-Walker cosmologies leading to the $\Lambda$CDM
model: an apparently flat Universe, dominated by a cosmological constant, whose
matter component is dominantly dark. We describe and discuss the various
observational probes that led to this conclusion and conclude that the
$\Lambda$CDM model, although leaving a number of open questions concerning the
deep nature of the constituents of the Universe, provides the best theoretical
framework to explain the observations.


title:
Micro-displacement sensors based on plastic photonic bandgap Bragg
  fibers

abstract:
  We demonstrate an amplitude-based micro-displacement sensor that uses a
plastic photonic bandgap Bragg fiber with one end coated with a silver layer.
The reflection intensity of the Bragg fiber is characterized in response to
different displacements (or bending curvatures). We note that the Bragg
reflector of the fiber acts as an efficient mode stripper for the wavelengths
near the edge of the fiber bandgap, which makes the sensor extremely sensitive
to bending or displacements at these wavelengths. Besides, by comparison of the
Bragg fiber sensor to a sensor based on a regular multimode fiber with similar
outer diameter and length, we find that the Bragg fiber sensor is more
sensitive to bending due to presence of mode stripper in the form of the
multilayer reflector. Experimental results show that the minimum detection
limit of the Bragg fiber sensor can be smaller than 5 um for displacement
sensing.


title: Clustering for multivariate continuous and discrete longitudinal data

abstract:
  Multiple outcomes, both continuous and discrete, are routinely gathered on
subjects in longitudinal studies and during routine clinical follow-up in
general. To motivate our work, we consider a longitudinal study on patients
with primary biliary cirrhosis (PBC) with a continuous bilirubin level, a
discrete platelet count and a dichotomous indication of blood vessel
malformations as examples of such longitudinal outcomes. An apparent
requirement is to use all the outcome values to classify the subjects into
groups (e.g., groups of subjects with a similar prognosis in a clinical
setting). In recent years, numerous approaches have been suggested for
classification based on longitudinal (or otherwise correlated) outcomes,
targeting not only traditional areas like biostatistics, but also rapidly
evolving bioinformatics and many others. However, most available approaches
consider only continuous outcomes as a basis for classification, or if
noncontinuous outcomes are considered, then not in combination with other
outcomes of a different nature. Here, we propose a statistical method for
clustering (classification) of subjects into a prespecified number of groups
with a priori unknown characteristics on the basis of repeated measurements of
several longitudinal outcomes of a different nature. This method relies on a
multivariate extension of the classical generalized linear mixed model where a
mixture distribution is additionally assumed for random effects. We base the
inference on a Bayesian specification of the model and simulation-based Markov
chain Monte Carlo methodology. To apply the method in practice, we have
prepared ready-to-use software for use in R (http://www.R-project.org). We also
discuss evaluation of uncertainty in the classification and also discuss usage
of a recently proposed methodology for model comparison - the selection of a
number of clusters in our case - based on the penalized posterior deviance
proposed by Plummer [Biostatistics 9 (2008) 523-539].


title:
Origin of n- and p-type conductivity in undoped $\alpha$-PbO: role of
  defects

abstract:
  The first principles calculations (GGA) have been applied to study the
crystallographic defects in $\alpha$-PbO in order to understand an origin of
$n$- and $p$-type conductivity in otherwise undoped $\alpha$-PbO. It was found
that deposition in the oxygen-deficient environment to be defined in our
simulations by the Pb-rich/O-poor limit stimulates a formation of the O
vacancies and the Pb interstitials both to be characterized by quite low
formation energies $\sim$ 1.0 eV. The O vacancy being occupied by two electrons
shifts a balance of electrons and holes between these two defects to excess of
electrons (four electrons against two holes) that causes the $n$-type doping.
For the Pb-poor/O-rich limit, an excess of oxygen triggers a formation of the O
interstitials characterized by such a low formation energy that spontaneous
appearance of this defect is predicted. It is shown that the concentration of
the O interstitials is able to reach the extreme magnitude equal to number of
the possible defect sites ($\sim 10^{22}$cm$^{-3}$). The localized state formed
by the O interstitial is occupied by two holes and because there are no other
defects in reasonable concentration to balance the hole redundancy, $p$-type
doping is induced.


title:
Kolmogorov-Sinai entropy via separation properties of order-generated
  sigma-algebras

abstract:
  In a recent paper, K.Keller has given a characterization of the
Kolmogorov-Sinai entropy of a discrete-time measure-preserving dynamical system
on the base of an increasing sequence of special partitions. These partitions
are constructed from order relations obtained via a given real-valued random
vector, which can be interpreted as a collection of observables on the system
and is assumed to separate points of it. In the present paper we relax the
separation condition in order to generalize the given characterization of
Kolmogorov-Sinai entropy, providing a statement on equivalence of
sigma-algebras. On its base we show that in the case that a dynamical system is
living on an m-dimensional smooth manifold and the underlying measure is
Lebesgue absolute continuous, the set of smooth random vectors of dimension n>m
with given characterization of Kolmogorov-Sinai entropy is large in a certain
sense.


title:
The role of the Seiberg-Witten field redefinition in renormalization of
  noncommutative chiral electrodynamics

abstract:
  It has been conjectured in the literature that renormalizability of the
$\theta$-expanded noncommutative gauge theories improves when one takes into
account full nonuniqueness of the Seiberg-Witten expansion, which relates
noncommutative (`high-energy') with commutative (`low-energy') fields. In order
to check this conjecture we analyze renormalizability of the noncommutative
chiral electrodynamics: we quantize the action which contains all possible
terms implied by the SW map. After renormalization we arrive at a different
theory in which the relation between the coupling constants is changed. This
means that the $\theta$-expanded chiral electrodynamics is not renormalizable:
when fermions are included, the SW expansion is not preserved in quantization.


title:
A progenitor binary and an ejected mass donor remnant of faint type Ia
  supernovae

abstract:
  Type Ia supernovae (SN Ia) are the most important standard candles for
measuring the expansion history of the universe. The thermonuclear explosion of
a white dwarf can explain their observed properties, but neither the progenitor
systems nor any stellar remnants have been conclusively identified.
Underluminous SN Ia have been proposed to originate from a so-called
double-detonation of a white dwarf. After a critical amount of helium is
deposited on the surface through accretion from a close companion, the helium
is ignited causing a detonation wave that triggers the explosion of the white
dwarf itself. We have discovered both shallow transits and eclipses in the
tight binary system CD-30 11223 composed of a carbon/oxygen white dwarf and a
hot helium star, allowing us to determine its component masses and fundamental
parameters. In the future the system will transfer mass from the helium star to
the white dwarf. Modelling this process we find that the detonation in the
accreted helium layer is sufficiently strong to trigger the explosion of the
core. The helium star will then be ejected at so large a velocity that it will
escape the Galaxy. The predicted properties of this remnant are an excellent
match to the so-called hypervelocity star US 708, a hot, helium-rich star
moving at more than 750 km/s, sufficient to leave the Galaxy. The
identification of both progenitor and remnant provides a consistent picture of
the formation and evolution of underluminous type Ia supernovae.


title:
Engineering Parallel Algorithms for Community Detection in Massive
  Networks

abstract:
  The amount of graph-structured data has recently experienced an enormous
growth in many applications. To transform such data into useful information,
fast analytics algorithms and software tools are necessary. One common graph
analytics kernel is disjoint community detection (or graph clustering). Despite
extensive research on heuristic solvers for this task, only few parallel codes
exist, although parallelism will be necessary to scale to the data volume of
real-world applications. We address the deficit in computing capability by a
flexible and extensible community detection framework with shared-memory
parallelism. Within this framework we design and implement efficient parallel
community detection heuristics: A parallel label propagation scheme; the first
large-scale parallelization of the well-known Louvain method, as well as an
extension of the method adding refinement; and an ensemble scheme combining the
above. In extensive experiments driven by the algorithm engineering paradigm,
we identify the most successful parameters and combinations of these
algorithms. We also compare our implementations with state-of-the-art
competitors. The processing rate of our fastest algorithm often reaches 50M
edges/second. We recommend the parallel Louvain method and our variant with
refinement as both qualitatively strong and fast. Our methods are suitable for
massive data sets with billions of edges.


title: Admittance of the SU(2) and SU(4) Anderson quantum RC circuits

abstract:
  We study the Anderson model as a description of the quantum RC circuit for
spin-1/2 electrons and a single level connected to a single lead. Our analysis
relies on the Fermi liquid nature of the ground state which fixes the form of
the low energy effective model. The constants of this effective model are
extracted from a numerical solution of the Bethe ansatz equations for the
Anderson model. They allow us to compute the charge relaxation resistance Rq in
different parameter regimes. In the Kondo region, the peak in Rq as a function
of the magnetic field is recovered and proven to be in quantitative agreement
with previous numerical renormalization group results. In the
valence-fluctuation region, the peak in Rq is shown to persist, with a maximum
value of h/2e^2, and an analytical expression is obtained using perturbation
theory. We extend our analysis to the SU(4) Anderson model where we also derive
the existence of a giant peak in the charge relaxation resistance.


title: The gravitational wave signal from isolated objects

abstract:
  According to the theoretical study, a deformation object (e.g., a spinning
non-axisymmetric pulsar star) will radiate a gravitational wave (GW) signal
during an accelaration motion process by LIGO science project. These types of
disturbance sources with a large bump or dimple on the equator would survive
and be identifiable as GW sources. In this work, we aim to provide a method for
exploring GW radiation from isolated neutron stars (NSs) with deformation state
using some observational results, which can be confirmed by the next LIGO
project. Combination with the properties in observation results (e.g., PSR
J1748-2446, PSR 1828-11 and Cygnus X-1), based on a binary population synthesis
(BPS) approach we give a numerical GW radiation under the assumption that NS
should have non-axisymmetric and give the results of energy spectrum. We find
that the GW luminosity of $L_{GW}$ can be changed from about $10^{40}\rm
erg/s$-- $10^{55}\rm erg/s$.


title:
Three orders of magnitude cavity-linewidth narrowing by slow light in a
  rare-earth-ion-doped crystal cavity

abstract:
  Three orders of magnitude cavity-linewidth narrowing in a
rare-earth-ion-doped crystal cavity, induced by strong intra-cavity dispersion
caused by off-resonant interaction with dopant ions is demonstrated. The strong
dispersion is created by semi-permanent but rapidly reprogrammable changes of
the rare earth absorption profiles using optical pumping techniques. Several
cavity modes are shown within the spectral transmission window. Potential
applications are discussed.


title: On pair functions for strong correlations

abstract:
  The UHF wave function may be written as a spin-contaminated \textit{pair}
wave function of the APSG form, and the overlap of the alpha and beta
corresponding orbitals of the UHF solution can be taken as a proxy for the
strength of the correlation captured by breaking symmetry. We demonstrate this
with calculations on one- and two-dimensional hydrogen clusters and make
contact with the well studied Hubbard model. The UHF corresponding orbitals
pair in a manner that allows a smooth evolution from doubly occupied orbitals
at small distance to one in which wave function breaks symmetry, segregating
the $\alpha$ and $\beta$ electrons onto distinct sublattices at large
distances. By performing spin projection on these UHF solutions, we address
strong correlations that are difficult to capture at intermediate distances
using a single determinant. Approved for public release: LA-UR-13-22691.


title:
Hidden-charmonium decays of $Z_c(3900)$ and $Z_c(4025)$ in intermediate
  meson loops model

abstract:
  The BESIII collaboration reported an observation of two charged
charmonium-like structure $Z_c^{\pm}(3900)$ and $Z_c^{\pm}(4025)$ in $e^+e^-
\to (J/\psi \pi)^{\pm} \pi^{\mp}$ and $e^+e^- \to (D^* {\bar D}^*)^{\pm}
\pi^{\mp}$ at ${\sqrt s} =4.26$ GeV recently, which could be an analogue of
$Z_b(10610)$ and $Z_b(10650)$ claimed by the Belle Collaboration. In this work,
we investigate the hidden-charmonium transitions of $Z_c^{\pm}(3900)$ and
$Z_c^{\pm}(4025)$ via intermediate $D^{(*)} {D}^{(*)}$ meson loops. Reasonable
results for the branching ratios by taking appropriate values of $\alpha$ in
this model can be obtained, which shows that the intermediate $D^{(*)}
{D}^{(*)}$ meson loops process may be a possible mechanism in these decays. Our
results are consistent with the power-counting analysis, and comparable with
the calculations in the framework of nonrelativistic effective field theory to
some extent. We expect more experimental measurements on these
hidden-charmonium decays and search for the decays of $Z_c\to D{\bar D}^*
+c.c.$ and $Z_c^\prime \to D^* {\bar D}^*$, which will help us investigate the
$Z_c^{(\prime)}$ decays deeply.


title:
Kinetic arrest related to a first-order ferrimagnetic to
  antiferromagnetic transition in the Heusler compound Mn2PtGa

abstract:
  We report a magnetization study of the Heusler compound Mn2PtGa that shows
the existence of a magnetic-glass state. Mn2PtGa shows a first-order
ferromagnetic (FM)/ferrimagnetic (FI) to antiferromagnetic (AFM) transition in
contrast to the martensitic structural transition observed in several Heusler
alloys. The kinetic arrest of this first-order FM (FI) to AFM transition leads
to the observed magnetic-glass behavior. We show that the strength of the
applied magnetic field, which is the primary parameter to induce the
magnetic-glass state, is also responsible for the stability of the supercooled
FM (FI) phase in time.


title: Can we always sweep the details of RNA-processing under the carpet?

abstract:
  RNA molecules follow a succession of enzyme-mediated processing steps from
transcription until maturation. The participating enzymes, for example the
spliceosome for mRNAs and Drosha and Dicer for microRNAs, are also produced in
the cell and their copy-numbers fluctuate over time. Enzyme copy-number changes
affect the processing rate of the substrate molecules; high enzyme numbers
increase the processing probability, low enzyme numbers decrease it. We study
different RNA processing cascades where enzyme copy-numbers are either fixed or
fluctuate. We find that for fixed enzyme-copy numbers the substrates at
steady-state are Poisson-distributed, and the whole RNA cascade dynamics can be
understood as a single birth-death process of the mature RNA product. In this
case, solely fluctuations in the timing of RNA processing lead to variation in
the number of RNA molecules. However, we show analytically and numerically that
when enzyme copy-numbers fluctuate, the strength of RNA fluctuations increases
linearly with the RNA transcription rate. This linear effect becomes stronger
as the speed of enzyme dynamics decreases relative to the speed of RNA
dynamics. Interestingly, we find that under certain conditions, the RNA cascade
can reduce the strength of fluctuations in the expression level of the mature
RNA product. Finally, by investigating the effects of processing polymorphisms
we show that it is possible for the effects of transcriptional polymorphisms to
be enhanced, reduced, or even reversed. Our results provide a framework to
understand the dynamics of RNA processing.


title: Resonant delocalization on the Bethe strip

abstract:
  Recently, Aizenman and Warzel discovered a mechanism for the appearance of
absolutely continuous spectrum for random Schroedinger operators on the Bethe
lattice through rare resonances (resonant delocalization). We extend their
analysis to operators with matrix-valued random potentials drawn from ensembles
such as the Gaussian Orthogonal Ensemble. These operators can be viewed as
random operators on the Bethe strip, a graph (lattice) with loops.


title:
Existence and multiplicity of solutions for a prescribed mean-curvature
  problem with critical growth

abstract:
  In this work we study an existence and multiplicity result for the following
prescribed mean-curvature problem with critical growth $$
\left\{\begin{array}{rl}
  -\mbox{div}\biggl(\frac{\nabla u}{\sqrt{1+|\nabla u|^{2}}}\biggl) = \lambda
|u|^{q-2}u+ |u|^{2^*-2}u & \mbox{in $\Omega$} u = 0 & \mbox{on $\partial
\Omega$}, \end{array} \right. $$ where $\Omega$ is a bounded smooth domain of
$\mathbb{R}^{N}$, $N\geq 3$ and $1 < q<2$. In order to employ variational
arguments, we consider an auxiliary problem which is proved to have infinitely
many solutions by genus theory. A clever estimate in the gradient of the
solutions of the modified problem is necessary to recover solutions of the
original one.


title: Distinguished conjugacy classes and elliptic Weyl group elements

abstract:
  We define and study a correspondence between the set of distinguished
G^0-conjugacy classes in a fixed connected component of a reductive group G
(with G^0 almost simple) and the set of (twisted) elliptic conjugacy classes in
the Weyl group. We also prove a homogeneity property related to this
correspondence.


title: The Deterministic Multicast Capacity of 4-Node Relay Networks

abstract:
  In this paper, we completely characterize the deterministic capacity region
of a four-node relay network with no direct links between the nodes, where each
node communicates with the three other nodes via a relay. Towards this end, we
develop an upper bound on the deterministic capacity region, based on the
notion of a one-sided genie. To establish achievability, we use the detour
schemes that achieve the upper bound by routing specific bits via indirect
paths instead of sending them directly.


title:
Partial Mass Degenerated Model and Spontaneous CP Violation in the
  Leptonic Sector

abstract:
  We have investigated a flavour model [1] which inspired by small squared-mass
difference measured in solar neutrino oscillation experiments and observability
in neutrinoless double beta decay experiments. In our model, the $1^{\rm st.}$
and $2^{\rm nd.}$ generations of fermions have a common mass at the leading
order. Such limit may be a good starting point from the points of view of
understanding the mixing patterns and mass spectra. In this limit, the mass
matrices are respected an $O (2)$ symmetry on flavor space of the first two
generations. For simplicity, we propose a model for lepton sector based on the
$D_N$ group which is a discrete subgroup of $O (2)$. We show that our model can
reproduce the experimental data without hierarchical couplings except for $5
\mathchar`- 10%$ tuning partially for the large neutrino mixing. Further, we
show a novel relation between the tiny electron mass and the relatively large
$\theta_{13}^{\rm PMNS}$ via CP violation by the complex vacuum expectation
values of the extra scalar fields.


title: Dark Entangled Steady States of Interacting Rydberg Atoms

abstract:
  We propose a scheme for rapid generation of high fidelity steady state
entanglement between a pair of atoms. A two-photon excitation process towards
long-lived Rydberg states with finite pairwise interaction, a dark state
interference effect in the individual atoms, and spontaneous emission from
their short-lived excited states lead to rapid, dissipative formation of an
entangled steady state. We show that for a wide range of physical parameters,
this entangled state is formed on a time scale given by the strengths of
coherent Raman and Rabi fields applied to the atoms, while it is only weakly
dependent on the Rydberg interaction strength.


title: On the Glitch Evolution of Pulsars

abstract:
  Observations of pulsar glitches remain a powerful tool for studying the
interior of neutron stars. Many of the observed glitch properties are shown to
result from the evolution of glitches in the different manifestations of
neutron stars. Specifically, the type of glitches associated with the Crab and
Vela pulsars are explained by this model. We are, also, able to adequately
account for the absence, or very low rate, of glitches among the youngest and
the very old pulsars.


title:
The interactions between comminution, segregation and remixing in
  granular flows

abstract:
  Granular segregation is an important mechanism for industrial processes
aiming at mixing grains. Additionally, it plays a pivotal role in determining
the kinematics of geophysical flows. Because of segregation, the grainsize
distribution varies in space and time. Additional complications arise from the
presence of comminution, where new particles are created, enhancing
segregation. This has a feedback on the comminution process, as particles
change their local neighbourhood. Simultaneously, particles are generally
undergoing remixing, further complicating the segregation and comminution
processes. The interaction between these mechanisms is explored using a
cellular automaton with three rules: one for each of segregation, comminution
and mixing. The interplay between these rules creates complex patterns, as seen
in segregating systems, and depth dependent grading curves, which have been
observed in avalanche runout. At every depth, log-normal grading curves are
produced at steady state, as measured experimentally in avalanche and debris
flow deposits.


title:
Weak convergence of finite-dimensional distributions of the number of
  empty boxes in the Bernoulli sieve

abstract:
  The Bernoulli sieve is a random allocation scheme obtained by placing
independent points with the uniform [0,1] law into the intervals made up by
successive positions of a multiplicative random walk with factors taking values
in the interval (0,1). Assuming that the number of points is equal to n we
investigate the weak convergence, as n tends to infinity, of finite-dimensional
distributions of the number of empty intervals within the occupancy range. A
new argument enables us to relax the constraints imposed in previous papers on
the distribution of the factor of the multiplicative random walk.


title:
Hybrid functionals for solids with an optimized Hartree-Fock mixing
  parameter

abstract:
  (Screened) hybrid functionals are being used more and more for solid-state
calculations. Usually the fraction alpha of Hartree-Fock exchange is kept fixed
during the calculation, however there is no single (universal) value for alpha
which systematically leads to satisfying accuracy. Instead, one could use a
property of the system under consideration to determine alpha and in this way
the functional would be more flexible and potentially more accurate. Recently,
it was proposed to use the static dielectric constant epsilon for the
calculation of alpha [Shimazaki and Asai, Chem. Phys. Lett. 466, 91 (2008) and
Marques et al., Phys. Rev. B 83, 035119 (2011)]. We explore this idea further
and propose a scheme where the connection between epsilon and alpha is
optimized based on experimental band gaps. epsilon, and thus alpha, is
recalculated at each iteration of the self-consistent procedure. We present
results for the band gap and lattice constant of various semiconductors and
insulators with this procedure. In addition, we show that this approach can
also be combined with a non-self-consistent hybrid approximation to speed up
the calculations considerably, while retaining an excellent accuracy in most
cases.


title:
The Control Complexity of $r$-Approval: from the Single-Peaked Case to
  the General Case

abstract:
  We investigate the complexity of $r$-Approval control problems in $k$-peaked
elections, where at most $k$ peaks are allowed in each vote with respect to an
order of the candidates. We show that most NP-hardness results in general
elections also hold in k-peaked elections even for $k=2,3$. On the other hand,
we derive polynomial-time algorithms for some problems for $k=2$. All our
NP-hardness results apply to Approval and sincere-strategy preference-based
Approval as well. Our study leads to many dichotomy results for the problems
considered in this paper, with respect to the values of $k$ and $r$. In
addition, we study $r$-Approval control problems from the viewpoint of
parameterized complexity and achieve both fixed-parameter tractability results
and W-hardness results, with respect to the solution size. Along the way
exploring the complexity of control problems, we obtain two byproducts which
are of independent interest. First, we prove that every graph of maximum degree
3 admits a specific 2-interval representation where every 2-interval
corresponding to a vertex contains a trivial interval and, moreover,
2-intervals may only intersect at the endpoints of the intervals. Second, we
develop a fixed-parameter tractable algorithm for a generalized $r$-Set Packing
problem with respect to the solution size, where each element in the given
universal set is allowed to occur in more than one r-subset in the solution.


title:
An analytic study of a distributed EDCA-based QoS mapping for layered
  video delivery in WLAN

abstract:
  One of the key challenges in multimedia networks is video delivery over
wireless channels. MRC (Multi-Resolution Coding) Layered video, divides video
into a base layer and multiple enhancement layers. In this paper, we aim to
improve video quality, impacted by high channel contention, through mapping
individual video layers to EDCA (Enhanced Distributed Channel Access) access
categories in order to maximize the average number of reconstructed video
layers. We propose an adaptive cross layer video layers mapping technique that
optimally enhances the QoS of wireless video transmission over IEEE 802.11e
EDCA priority queues. The optimization is based on a dynamic program that takes
into account the EDCA parameters and the layered dependency nature of layered
video delivery. Our proposed technique makes use of a channel delay estimation
model and an estimation of average video useful layers delivered. The optimal
mapping strategies are selected by an optimization module based on the
information from the analytical model. The accuracy of our optimized mapping
technique performance is verified through extensive simulations. The obtained
results illustrate significant trade-off between complexity and delivered video
quality for canonical mapping schemes.


title: Efficient sampling of fast and slow cosmological parameters

abstract:
  Physical parameters are often constrained from the data likelihoods using
sampling methods. Changing some parameters can be much more computationally
expensive (`slow') than changing other parameters (`fast parameters'). I
describe a method for decorrelating fast and slow parameters so that parameter
sampling in the full space becomes almost as efficient as sampling in the slow
subspace when the covariance is well known and the distributions are simple.
This gives a large reduction in computational cost when there are many fast
parameters. The method can also be combined with a fast 'dragging' method
proposed by Neal (2005) that can be more robust and efficient when parameters
cannot be fully decorrelated a priori or have more complicated dependencies. I
illustrate these methods for the case of cosmological parameter estimation
using data likelihoods from the Planck satellite observations with dozens of
fast nuisance parameters, and demonstrate a speed up by a factor of five or
more. In more complicated cases, especially where the fast subspace is very
fast but complex or highly correlated, the fast-slow sampling methods can in
principle give arbitrarily large performance gains. The new samplers are
implemented in the latest version of the publicly available CosmoMC code.


title:
COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XII.
  Time delays of the doubly lensed quasars SDSS J1206+4332 and HS 2209+1914

abstract:
  Aims. Within the framework of the COSMOGRAIL collaboration we present 7- and
8.5-year-long light curves and time-delay estimates for two gravitationally
lensed quasars: SDSS J1206+4332 and HS 2209+1914. Methods. We monitored these
doubly lensed quasars in the R-band using four telescopes: the Mercator,
Maidanak, Himalayan Chandra, and Euler Telescopes, together spanning a period
of 7 to 8.5 observing seasons from mid-2004 to mid-2011. The photometry of the
quasar images was obtained through simultaneous deconvolution of these data.
The time delays were determined from these resulting light curves using four
very different techniques: a dispersion method, a spline fit, a regression
difference technique, and a numerical model fit. This minimizes the bias that
might be introduced by the use of a single method. Results. The time delay for
SDSS J1206+4332 is Delta_t AB = 111.3 +/- 3 days with A leading B, confirming a
previously published result within the error bars. For HS 2209+1914 we present
a new time delay of Delta_t BA = 20.0 +/- 5 days with B leading A. Conclusions.
The combination of data from up to four telescopes have led to well-sampled and
nearly 9-season-long light curves, which were necessary to obtain these
results, especially for the compact doubly lensed quasar HS 2209+1914.


title: A priori estimates for excitable models

abstract:
  The reaction-diffusion system of Fitzhugh Nagumo is considered. The initial-
boundary problems with Neumann and Dirichlet conditions are analyzed. By means
of an equivalent semilinear integrodifferential equation which characterizes
several dissipative models of viscoelasticity, biology, and superconductivity,
some results on existence, uniqueness and a priori estimates are deduced both
in the linear case and in the non linear one.


title: What Causes Cost Overrun in Transport Infrastructure Projects?"

abstract:
  This article presents results from the first statistically significant study
of causes of cost escalation in transport infrastructure projects. The study is
based on a sample of 258 rail, bridge, tunnel and road projects worth US$90
billion. The focus is on the dependence of cost escalation on (1) length of
project implementation phase, (2) size of project and (3) type of project
ownership. First, it is found with very high statistical significance that cost
escalation is strongly dependent on length of implementation phase. The policy
implications are clear: Decision makers and planners should be highly concerned
about delays and long implementation phases because they translate into risks
of substantial cost escalations. Second, it is found that projects have grown
larger over time and that for bridges and tunnels larger projects have larger
percentage cost escalations. Finally, by comparing cost escalation for three
types of project ownership--private, state-owned enterprise and other public
ownership--it is shown that the oft-seen claim that public ownership is
problematic and private ownership effective in curbing cost escalation is an
oversimplification. Type of accountability appears to matter more to cost
escalation than type of ownership.


title: Quantum Secret Sharing with Continuous Variable Graph State

abstract:
  In this paper we study the protocol implementation and property analysis for
several practical quantum secret sharing (QSS) schemes with continuous variable
graph state (CVGS). For each QSS scheme, an implementation protocol is designed
according to its secret and communication channel types. The estimation error
is derived explicitly, which facilitates the unbiased estimation and error
variance minimization. It turns out that only under infinite squeezing can the
secret be perfectly reconstructed. Furthermore, we derive the condition for QSS
threshold protocol on a weighted CVGS. Under certain conditions, the perfect
reconstruction of the secret for two non-cooperative groups is exclusive, i.e.
if one group gets the secret perfectly, the other group cannot get any
information about the secret.


title:
Coexistence of spin-triplet superconductivity with magnetism within a
  single mechanism for orbitally degenerate correlated electrons:
  Statistically-consistent Gutzwiller approximation

abstract:
  An orbitally degenerate two-band Hubbard model is analyzed with inclusion of
the Hund's rule induced spin-triplet paired states and their coexistence with
magnetic ordering. The so-called statistically consistent Gutzwiller
approximation (SGA) has been applied to the case of a square lattice. The
superconducting gaps, the magnetic moment, and the free energy are analyzed as
a function of the Hund's rule coupling strength and the band filling. Also, the
influence of the intersite hybridization on the stability of paired phases is
discussed. In order to examine the effect of correlations the results are
compared with those calculated earlier within the Hartree-Fock (HF)
approximation combined with the Bardeen-Cooper-Schrieffer (BCS) approach.
Significant differences between the two used methods (HF+BCS vs. SGA+real-space
pairing) appear in the stability regions of the considered phases. Our results
supplement the analysis of this canonical model used widely in the discussions
of pure magnetic phases with the detailed elaboration of the stability of the
spin-triplet superconducting states and the coexistent magnetic-superconducting
states. At the end, we briefly discuss qualitatively the factors that need to
be included for a detailed quantitative comparison with the corresponding
experimental results.


title: Optimizing snake locomotion in the plane. I. Computations

abstract:
  We develop a numerical scheme to determine which planar snake motions are
optimal for locomotory efficiency, across a wide range of frictional parameter
space. For a large coefficient of transverse friction, we find that retrograde
traveling waves are optimal. The optimal snake deflection scales as the -1/4
power of the coefficient of transverse friction, in agreement with an
asymptotic analysis. At the other extreme, zero coefficient of transverse
friction, we propose a triangular direct wave which is optimal. Between these
two extremes, a variety of complex, locally optimal motions are found. Some of
these can be classified as standing waves (or ratcheting motions).


title: An infinite family of 2-groups with mixed Beauville structures

abstract:
  We construct an infinite family of triples $(G_k,H_k,T_k)$, where $G_k$ are
2-groups of increasing order, $H_k$ are index-2 subgroups of $G_k$, and $T_k$
are pairs of generators of $H_k$. We show that the triples $u_k =
(G_k,H_k,T_k)$ are mixed Beauville structures if $k$ is not a power of 2. This
is the first known infinite family of 2-groups admitting mixed Beauville
structures. Moreover, the associated Beauville surface $S(u_3)$ is real and,
for $k > 3$ not a power of 2, the Beauville surface $S(u_k)$ is not
biholomorphic to $\bar{S(u_k)}$.


title: Almost dual pairs and definable classes of modules

abstract:
  Holm (H. Holm, Modules with cosupport and injective functors, Algebr.
Represent. Theor., 13 (2010), 543-560) considers categories of right modules
dual to those with support in a set of finitely presented modules. We extend
some of his results by placing them in the context of elementary duality on
definable subcategories


title: Jointly orthogonal polynomials

abstract:
  The theory of polynomials orthogonal with respect to one inner product is
classical. We discuss the extension of this theory to multiple inner products.
Examples include the Lam\'e and Heine-Stieltjes polynomials.


title: Heat Transport in Confined Strongly Coupled 2D Dust Clusters

abstract:
  Dusty plasmas are a model system for studying strong correlation. The dust
grains' size of a few micro-meters and their characteristic oscillation
frequency of a few hertz allows for an investigation of many particle effects
on an atomic level. In this article, we model the heat transport through an
axially confined 2D dust cluster from the center to the outside. The system
behaves particularly interesting since heat is not only conducted within the
dust component but also transfered to the neutral gas. Fitting the analytical
solution to the obtained radial temperature profiles allows to determine the
heat conductivity $\kheat$. The heat conductivity is found to be constant over
a wide range of coupling strengths even including the phase transition from
solid to liquid here, as it was also found in extended systems by V. Nosenko et
al. in 2008 \cite{PhysRevLett.100.025003}


title:
Magnetic excitation spectrum of Na2IrO3 probed with resonant inelastic
  x-ray scattering

abstract:
  The low energy excitations in Na2IrO3 have been investigated using resonant
inelastic x-ray scattering (RIXS). A magnetic excitation branch can be
resolved, whose dispersion reaches a maximum energy of about 35 meV at the
\Gamma-point. The momentum dependence of the excitation energy is much larger
along the \Gamma-X direction compared to that along the \Gamma-Y direction. The
observed dispersion relation is consistent with a recent theoretical prediction
based on Heisenberg-Kitaev model. At high temperatures, we find large
contributions from lattice vibrational modes to our RIXS spectra, suggesting
that a strong electron-lattice coupling is present in Na2IrO3.


title: Optimizing snake locomotion in the plane. II. Large transverse friction

abstract:
  We determine analytically the form of optimal snake locomotion when the
coefficient of transverse friction is large, the typical regime for biological
and robotic snakes. We find that the optimal snake motion is a retrograde
traveling wave, with a wave amplitude that decays as the -1/4 power of the
coefficient of transverse friction. This result agrees well with our numerical
computations.


title: Composite Fermion states on the torus

abstract:
  We extend the composite fermion construction to the torus geometry. We verify
the validity of our construction by computing the overlap of the composite
fermion state to the exact diagonalization ground state of both Coulomb
interaction and Haldane-pseudopotential interaction V_0 (V_1) for bosonic
(fermionic) states.


title: Aharonov-Casher Effect for Plasmons in a Ring of Josephson Junctions

abstract:
  Phase slips in a one-dimensional closed array of Josephson junctions
hybridize the persistent current states (PCS) and plasmon branches of
excitations. The interference between phase slips passing through different
junctions of the array makes the hybridization sensitive to the charges of the
superconducting islands comprising the array. This in turn results in the
Aharonov-Casher effect for plasmons, which in absence of phase slips are
insensitive to island charges.


title: Multitasking network with fast noise

abstract:
  We consider the multitasking associative network in the low-storage limit and
we study its phase diagram with respect to the noise level $T$ and the degree
$d$ of dilution in pattern entries. We find that the system is characterized by
a rich variety of stable states, among which pure states, parallel retrieval
states, hierarchically organized states and symmetric mixtures (remarkably,
both even and odd), whose complexity increases as the number of patterns $P$
grows. The analysis is performed both analytically and numerically: Exploiting
techniques based on partial differential equations, allows us to get the
self-consistencies for the order parameters. Such self-consistence equations
are then solved and the solutions are further checked through stability theory
to catalog their organizations into the phase diagram, which is completely
outlined at the end. This is a further step toward the understanding of
spontaneous parallel processing in associative networks.


title:
Existence of global strong solution for Korteweg system with large
  infinite energy initial data

abstract:
  This work is devoted to the study of the initial boundary value problem for a
general isothermal model of capillary fluids derived by J.E Dunn and J.Serrin
(1985), which can be used as a phase transition model. We will prove the
existence of local and global (under a condition of smallness on the initial
data) strong solutions with discontinuous initial density when $\ln\rho_{0}$
belongs in the Besov space $B^{\N}_{2,\infty}(\R^{N})$.The main difficulty
concerns the proof of new estimate of maximum principle type for the linear
system associated to the Korteweg system, the proof is based on a
characterization of the Besov space in terms of the semi group associated to
this linear system. Let also point out that we prove the existence of global
strong solution with a smallness hypothesis which is subcritical in terms of
the scaling of the equations, it allows us to exhibit a family of large energy
initial data for the scaling of the equations providing global strong solution.
In particular for the first time up our knowledge we show the existence of
global strong solution for some large energy initial data when N=2. We finish
this paper by introducing the notion of quasi-solutions for the Korteweg's
system (a tool which has been developed in the framework of the compressible
Navier-Stokes equations \cite{arxiv,arxiv1,hal,cras1,cras2}) which enables us
to improve the previous result and to obtain the existence of global strong
solution with large initial velocity in $B^{\N-1}_{2,\infty}$. As a corollary,
we get global existence (and uniqueness) for highly compressible Korteweg
system when $N\geq2$.


title: Structure of spaces with Bakry-\'Emery Ricci curvature bounded below

abstract:
  In this paper, we explore the limit structure of a sequence of Riemannian
manifolds with Bakry-\'Emery Ricci curvature bounded below in the
Gromov-Hausdorff topology. By extending the techniques established by
Cheeger-Cloding for Riemannian manifolds with Ricci curvature bounded below, we
prove that each tangent space at a point of the limit space is a metric cone.
We also analyze the singular structure of the limit space analogous to a work
of Cheeger-Colding-Tian. Our results will be applied to study the limit space
of a sequence of K\"ahler metrics arising from solutions of certain complex
Monge-Amp\`ere equations for the existence of K\"ahler-Ricci solitons on a Fano
manifold via the continuity method.


title:
Towards a bifurcation theory for perturbed monomial dynamical systems
  modulo a prime

abstract:
  We investigate perturbed monomial dynamical system over $\mathbb{F}_p$ given
by iterations of
  $x\mapsto x^n+c\bmod{p}$, where $c\in \mathbb{F}_p$. Instead of study the
systems one at a time we study all of them at the same time. The complex
distibution of periodic points is visualized in the so called Periodic Point
Diagram, which can be seen as a discrete version of the classical Bifurcation
Diagram. We also prove some general results about the distribution of periodic
points. We end the article with a conjecture about the total number of periodic
points.


title: Pauli channel tomography with unknown channel directions

abstract:
  In this paper we estimate the parameters of the qubit Pauli channel using the
channel matrix formalism. The main novelty of this work is that we do not
assume the directions of the Pauli channel to be known, but they are determined
through the tomography process, too. The results show that for optimally
estimating the contraction parameters and the channel matrix we should have
input qubits and measurements in the channel directions. However, for optimally
estimating the channel directions, we should use different tomography
conditions.


title: The Tully-Fisher relations for Hickson Compact Group galaxies

abstract:
  We used K-band photometry, maximum rotational velocities derived from
Fabry-Perot data and HI observed and predicted masses to study, for the first
time, the K-band, stellar and baryonic Tully-Fisher relations for galaxies in
Hickson compact groups. We compared these relations with the ones defined for
galaxies in less dense environments from the GHASP survey and from a sample of
gas-rich galaxies. We find that most of the Hickson compact group galaxies lie
on the K-band Tully-Fisher relation defined by field galaxies with a few
low-mass outliers, namely HCG 49b and HCG 96c, which appear to have had strong
recent burst of star formation. The stellar Tully-Fisher relation for compact
group galaxies presents a similar dispersion to that of the K-band relation,
and it has no significant outliers when a proper computation of the stellar
mass is done for the strongly star-forming galaxies. The scatter in these
relations can be reduced if the gaseous component is taken into account, i.e.,
if a baryonic Tully-Fisher relation is considered. In order to explain the
positions of the galaxies off the K-band Tully-Fisher relation we favour a
scenario in which their luminosities are brightened due to strong star
formation or AGN activity. We argue that strong bursts of star formation can
affect the B and K-band luminosities of HCG 49b and HCG 96c and in the case of
the latter also AGN activity may affect the K-band magnitude considerably,
without affecting their total masses.


title:
Uncovering quasi-degenerate Kaluza-Klein Electro-Weak gauge bosons with
  top asymmetries at the LHC

abstract:
  By exploiting the correlation between charge and spin polarisation
asymmetries in t-tbar, we show that combining the two observables could
identify the presence of quasi-degenerate states in a resonant signal at the
LHC. As an example, we investigate experimental signatures emerging in
top-antitop final states in the context of a model where the Standard Model
Electro-Weak sector is allowed to propagate in large extra--dimensions of
TeV^-1 size while the colour sector is localised. Assuming current experimantal
constraints from the 7 and 8 TeV runs and taking into account the estimated top
(anti-top) reconstruction efficiencies, we find that the 14 TeV upgraded LHC
with the planned integrated luminosity L=100 fb^-1 could access these
quasi-degenerate multiple resonances and explore for the first time the rich
phenomenology in the asymmetry observables. The main outcome would be having
measurable quantities, complementary to the usual total and differential cross
sections, capable of distiguishing a quasi-degenerate multiply resonant
spectrum from a `standard' single resonance that could present a similar signal
in a bump hunt analysis.


title: On linear systems and a conjecture of D. C. Butler

abstract:
  Let $C$ be a smooth irreducible projective curve of genus $g$ and $L$ a line
bundle of degree $d$ generated by a linear subspace $V$ of $H^0(L)$ of
dimension $n+1$. We prove a conjecture of D. C. Butler on the semistability of
the kernel of the evaluation map $V\otimes{\mathcal O}_C\to L$ and obtain new
results on the stability of this kernel. The natural context for this problem
is the theory of coherent systems on curves and our techniques involve wall
crossing formulae in this theory.


title: Stringy holography at finite density

abstract:
  We consider an exactly solvable worldsheet string theory in the background of
a black brane with a gauge field flux. Holographically, such a system can be
interpreted as a field theory with finite number of degrees of freedom at
finite temperature and density. This is to be contrasted with more conventional
holographic models which involve gravity in the bulk and possess infinite
number of degrees of freedom and mean field critical exponents. We construct
closed string vertex operators which holographically represent the U(1) gauge
field and the stress energy tensor and compute their two-point functions. At
finite temperature and vanishing charge density the low energy excitations are
described by hydrodynamics. As the density is raised, the system behaves like a
sum of two noninteracting fluids. We find low-energy excitations in the shear
and sound channels of each fluid.


title: Moments of the neutron $g_2$ structure function at intermediate $Q^2$

abstract:
  We present new experimental results of the $^3$He spin structure function
$g_2$ in the resonance region at $Q^2$ values between 1.2 and 3.0 (GeV/c)$^2$.
Spin dependent moments of the neutron were then extracted. Our main result, the
resonance contribution to the neutron $d_2$ matrix element, was found to be
small at $<Q^2>$=2.4 (GeV/c)$^2$ and in agreement with the Lattice QCD
calculation. The Burkhardt-Cottingham sum rule for $^3$He and the neutron was
tested with the measured data and using the Wandzura-Wilczek relation for the
low $x$ unmeasured region. A small deviation was observed at $Q^2$ values
between 0.5 and 1.2 (GeV/c)$^2$ for the neutron.


title: Phase diagram of hard board like colloids from computer simulations

abstract:
  The rich mesophase polymorhism and the phase sequence of board-like colloids
depends critically on their shape anisometry. Implementing extensive Monte
Carlo simulations, we calculated the full phase diagram of sterically
interacting board-like particles, for a range of experimentally accessible
molecular dimensions/anisometries of colloids of this shape. A variety of self
organized mesophases including uniaxial and biaxial nematics, smectic, cubatic
and columnar phases have been identified. Our results demonstrate clearly that
the molecular anisometry influences critically not only the structure and the
symmetry of the mesophases but also, and perhaps more interestingly, the phase
sequence among them. New classes of phase sequences such as nematic-nematic
and, for the first time, a direct transition from a discotic and a biaxial
nematic to an orthogonal smectic A phase have been identified. The molecular
geometry requirements for such a phase behavior have been located.


title:
Abstraction and Acceleration in SMT-based Model-Checking for Array
  Programs

abstract:
  Abstraction (in its various forms) is a powerful established technique in
model-checking; still, when unbounded data-structures are concerned, it cannot
always cope with divergence phenomena in a satisfactory way. Acceleration is an
approach which is widely used to avoid divergence, but it has been applied
mostly to integer programs. This paper addresses the problem of accelerating
transition relations for unbounded arrays with the ultimate goal of avoiding
divergence during reachability analysis of abstract programs. For this, we
first design a format to compute accelerations in this domain; then we show how
to adapt the so-called 'monotonic abstraction' technique to efficiently handle
complex formulas with nested quantifiers generated by the acceleration
preprocessing. Notably, our technique can be easily plugged-in into
abstraction/refinement loops, and strongly contributes to avoid divergence:
experiments conducted with the MCMT model checker attest the effectiveness of
our approach on programs with unbounded arrays, where acceleration and
abstraction/refinement technologies fail if applied alone.


title: Measurement of the effective B_s^0 -> J/{\psi} K_S^0 lifetime

abstract:
  This paper reports the first measurement of the effective B_s^0 -> J/{\psi}
K_S^0 lifetime and an updated measurement of its time-integrated branching
fraction. Both measurements are performed with a data sample, corresponding to
an integrated luminosity of 1.0 fb^{-1} of pp collisions, recorded by the LHCb
experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are:
tau_J/{\psi}K_S^0 = 1.75 +/- 0.12 (stat) +/- 0.07 (syst) and
  BR(B_s^0 -> J/{\psi} K_S^0) = (1.97 +/- 0.23) X 10^{-5}.
  For the latter measurement, the uncertainty includes both statistical and
systematic sources.


title:
Perfect memristor: non-volatility, switching and negative differential
  resistance

abstract:
  We propose a simple model of a nanoswitch as a memory resistor. The
resistance of the nanoswitch is determined by electron tunneling through a
nanoparticle diffusing around one or more potential minima located between the
electrodes in the presence of Joule's heat dissipation. In the case of a single
potential minimum, we observe hysteresis of the resistance at finite applied
currents and a negative differential resistance. For two (or more) minima the
switching mechanism is non-volatile, meaning that the memristor can switch to a
resistive state of choice and stay there. Moreover, the noise spectra of the
switch exhibit $1/f^2\rightarrow 1/f$ crossover, in agreement with recent
experimental results.


title:
Porous media, Fast diffusion equations and the existence of global weak
  solution for the quasi-solution of compressible Navier-Stokes equations

abstract:
  In \cite{arxiv,arxiv1,Kor,cras1,cras2}, we have developed a new tool called
\textit{quasi solutions} which approximate in some sense the compressible
Navier-Stokes equation. In particular it allows us to obtain global strong
solution for the compressible Navier-Stokes equations with \textit{large}
initial data on the irrotational part of the velocity (\textit{large} in the
sense that the smallness assumption is subcritical in terms of scaling, it
turns out that in this framework we are able to obtain a family of large
initial data in the energy space in dimension N=2). In this paper we are
interested in proving the result anounced in \cite{cras3} concerning the
existence of global weak solution for the quasi-solutions, we also observe that
for some choice of initial data (irrotationnal) the quasi solutions verify the
porous media, the heat equation or the fast diffusion equations in function of
the structure of the viscosity coefficients. In particular it implies that it
exists classical quasi-solutions in the sense that they are $C^{\infty}$ on
$(0,T)\times\R^{N}$ for any $T>0$. Finally we show the convergence of the
global weak solution of compressible Navier-Stokes equations to the quasi
solutions in the case of a vanishing pressure limit process. In particular we
show that for highly compressible equations the speed of propagation of the
density is quasi finite when the viscosity corresponds to
$\mu(\rho)=\rho^{\alpha}$ with $\alpha>1$. Furthermore the density is not far
from converging asymptotically in time to the Barrenblatt solution of mass the
initial density $\rho_{0}$.


title:
Analysis of a time discretization scheme for a nonstandard viscous
  Cahn-Hilliard system

abstract:
  In this paper we propose a time discretization of a system of two parabolic
equations describing diffusion-driven atom rearrangement in crystalline matter.
The equations express the balances of microforces and microenergy; the two
phase fields are the order parameter and the chemical potential. The initial
and boundary-value problem for the evolutionary system is known to be well
posed. Convergence of the discrete scheme to the solution of the continuous
problem is proved by a careful development of uniform estimates, by weak
compactness and a suitable treatment of nonlinearities. Moreover, for the
difference of discrete and continuous solutions we prove an error estimate of
order one with respect to the time step.


title: Experimental multi-location remote state preparation

abstract:
  Transmission of quantum states is a central task in quantum information
science. Remote state preparation (RSP) has the same goal as teleportation,
i.e. transferring quantum information without sending physically the
information carrier, but in RSP the sender knows the state which is to be
transmitted. We present experimental demonstrations of RSP for two and three
locations. In our experimental scheme Alice (the preparer) and her three
partners share four and six photon polarization entangled singlets. This allows
us to perform RSP of two or three copies of a single qubit states, a two qubit
Bell state, and a three qubit W, or inverse W state. A possibility to prepare a
two-qubit non-maximally entangled and GHZ states is also discussed. The ability
to remotely prepare an entangled states by local projections at Alice is a
distinguishing feature of our scheme.


title: Yaglom law in the expanding solar wind

abstract:
  We study the Yaglom law, which relates the mixed third order structure
function to the average dissipation rate of turbulence, in a uniformly
expanding solar wind by using the two scales expansion model of
magnetohydrodynamic (MHD) turbulence. We show that due to the expansion of the
solar wind two new terms appear in the Yaglom law. The first term is related to
the decay of the turbulent energy by nonlinear interactions, whereas the second
term is related to the non-zero cross-correlation of the Els\"asser fields.
Using magnetic field and plasma data from WIND and Helios 2 spacecrafts, we
show that at lower frequencies in the inertial range of MHD turbulence the new
terms become comparable to Yaglom's third order mixed moment, and therefore
they cannot be neglected in the evaluation of the energy cascade rate in the
solar wind.


title:
Lower bound of quantum uncertainty from extractable classical
  information

abstract:
  The sum of entropic uncertainties for the measurement of two non-commuting
observables is not always reduced by the amount of entanglement (quantum
memory) between two parties, and in certain cases may be impacted by quantum
correlations beyond entanglement (discord). An optimal lower bound of entropic
uncertainty in the presence of any correlations may be determined by
fine-graining. Here we express the uncertainty relation in a new form where the
maximum possible reduction of uncertainty is shown to be given by the
extractable classical information. We show that the lower bound of uncertainty
matches with that using fine-graining for several examples of two-qubit pure
and mixed entangled states, and also separable states with non-vanishing
discord.
  Using our uncertainty relation we further show that even in the absence of
any quantum correlations between the two parties, the sum of uncertainties may
be reduced with the help of classical correlations.


title: Search for $^{21}$C and constraints on $^{22}$C

abstract:
  A search for the neutron-unbound nucleus $^{21}$C was performed via the
single proton removal reaction from a beam of 22 N at 68 MeV/u. Neutrons were
detected with the Modular Neutron Array (MoNA) in coincidence with $^{20}$C
fragments. No evidence for a low-lying state was found, and the reconstructed
$^{20}$C+n decay energy spectrum could be described with an s-wave line shape
with a scattering length limit of |as| < 2.8 fm, consistent with shell model
predictions. A comparison with a renormalized zero-range three-body model
suggests that $^{22}$C is bound by less than 70 keV.


title: A classical model for derived critical loci

abstract:
  Let $f:U\to{\mathbb A}^1$ be a regular function on a smooth scheme $U$ over a
field $\mathbb K$. Pantev, Toen, Vaquie and Vezzosi (arXiv:1111.3209,
arXiv:1109.5213) define the "derived critical locus" Crit$(f)$, an example of a
new class of spaces in derived algebraic geometry, which they call
"$-1$-shifted symplectic derived schemes".
  They show that intersections of algebraic Lagrangians in a smooth symplectic
$\mathbb K$-scheme, and stable moduli schemes of coherent sheaves on a
Calabi-Yau 3-fold over $\mathbb K$, are also $-1$-shifted symplectic derived
schemes. Thus, their theory may have applications in algebraic symplectic
geometry, and in Donaldson-Thomas theory of Calabi-Yau 3-folds.
  This paper defines and studies a new class of spaces we call "algebraic
d-critical loci", which should be regarded as classical truncations of
$-1$-shifted symplectic derived schemes. They are simpler than their derived
analogues. We also give a complex analytic version of the theory, "complex
analytic d-critical loci", and an extension to Artin stacks, "d-critical
stacks".
  In the sequels arXiv:1305.6302, arXiv:1211.3259, arXiv:1305.6428,
arXiv:1312.0090 we will define truncation functors from $-1$-shifted symplectic
derived schemes or stacks to algebraic d-critical loci or d-critical stacks,
and we will apply d-critical loci to motivic and categorified Donaldson-Thomas
theory, and to intersections of (derived) complex Lagrangians in complex
symplectic manifolds. We will show that the important structures one wants to
associate to a derived critical locus -- virtual cycles, perverse sheaves and
mixed Hodge modules of vanishing cycles, and motivic Milnor fibres -- can be
defined for oriented d-critical loci and oriented d-critical stacks.


title: Analytic Continuation of the Doubly-periodic Barnes Zeta Function

abstract:
  The aim of this work is to study the analytic continuation of the
doubly-periodic Barnes zeta function. By using a suitable complex integral
representation as a starting point we find the meromorphic extension of the
doubly periodic Barnes zeta function to the entire complex plane in terms of a
real integral containing the Hurwitz zeta function and the first Jacobi theta
function. These allow us to explicitly give expressions for the derivative at
all non-positive integer points.


title:
Microwave and submillimeter molecular transitions and their dependence
  on fundamental constants

abstract:
  Microwave and submillimeter molecular transition frequencies between nearly
degenerated rotational levels, tunneling transitions, and mixed
tunneling-rotational transitions show an extremely high sensitivity to the
values of the fine-structure constant, alpha, and the electron-to-proton mass
ratio, mu. This review summarizes the theoretical background on
quantum-mechanical calculations of the sensitivity coefficients of such
transitions to tiny changes in alpha and mu for a number of molecules which are
usually observed in Galactic and extragalactic sources, and discusses the
possibility of testing the space- and time-invariance of fundamental constants
through comparison between precise laboratory measurements of the molecular
rest frequencies and their astronomical counterparts. In particular, diatomic
radicals CH, OH, NH+, and a linear polyatomic radical C3H in Pi electronic
ground state, polyatomic molecules NH3, ND3, NH2D, NHD2, H2O2, H3O+, CH3OH, and
CH3NH2 in their tunneling and tunneling-rotational modes are considered. It is
shown that sensitivity coefficients strongly depend on the quantum numbers of
the corresponding transitions. This can be used for astrophysical tests of
Einstein's Equivalence Principle all over the Universe at an unprecedented
level of sensitivity of ~10^-9, which is a limit three to two orders of
magnitude lower as compared to the current constraints on cosmological
variations of alpha and mu: Delta alpha/alpha < 10^-6, Delta mu/mu < 10^-7.

categories: physics.atom-ph astro-ph.CO hep-ph nucl-th


title:
Spin-orbit Coupling Effects on the Superfluidity of Fermi Gas in an
  Optical Lattice

abstract:
  We investigate the superfluidity of attractive Fermi gas in a square optical
lattice with spin-orbit coupling (SOC). We show that the system displays a
variety of new filling-dependent features. At half filling, a quantum phase
transition from a semimetal to a superfluid is found for large SOC. Close to
half filling where the emerging Dirac cones governs the behaviors of the
system, SOC tends to suppress the BCS superfluidity. Conversely, SOC can
significantly enhance both the pairing gap and condensate fraction and lead to
a new BCS-BEC crossover for small fillings. Moreover, we demonstrate that the
superfluid fraction also exhibits many interesting phenomena compared with the
spin-orbit coupled Fermi gas without lattice.


title:
Experimental Test of the Quantum Violation of the Noncontextuality
  Inequalities for the n-Cycle Scenario

abstract:
  The inequalities that separate contextual from noncontextual correlations for
the n-cycle scenario (consisting of n dichotomic observables Oj, with j = 0,
..., n-1 and such that Oj and Oj+1 are jointly measurable) have been recently
identified [arXiv:1206.3212 (2012)]. Here we report the results of an
experiment designed to reach the maximum quantum violation of these
inequalities for any even number of observables ranging from 4 to 14. The four
dimensional Hilbert space required for the test was spanned by two photonic
qubits encoded in the transversal path of photon pairs, and the joint
measurability of the observables is guaranteed by measuring correlations
between observables from different modes. Our results show contextual
correlations as predicted by quantum mechanics.


title:
The method of freezing as a new tool for nonlinear reduced basis
  approximation of parameterized evolution equations

abstract:
  We present a new method for the nonlinear approximation of the solution
manifolds of parameterized nonlinear evolution problems, in particular in
hyperbolic regimes with moving discontinuities. Given the action of a Lie group
on the solution space, the original problem is reformulated as a partial
differential algebraic equation system by decomposing the solution into a group
component and a spatial shape component, imposing appropriate algebraic
constraints on the decomposition. The system is then projected onto a reduced
basis space. We show that efficient online evaluation of the scheme is possible
and study a numerical example showing its strongly improved performance in
comparison to a scheme without freezing.


title:
Distance Priors from Planck and Dark Energy Constraints from Current
  Data

abstract:
  We derive distance priors from Planck first data release, and examine their
impact on dark energy constraints from current observational data. We give the
mean values and covariance matrix of {R, l_a, \Omega_b h^2, n_s}, which give an
efficient summary of Planck data. The CMB shift parameters are R=\sqrt{\Omega_m
H_0^2}\,r(z_*), and l_a=\pi r(z_*)/r_s(z_*), where z_* is the redshift at the
last scattering surface, and r(z_*) and r_s(z_*) denote our comoving distance
to z_* and sound horizon at z_* respectively.
  We find that Planck distance priors are significantly tighter than those from
WMAP9. However, adding Planck distance priors does not lead to significantly
improved dark energy constraints using current data, compared to adding WMAP9
distance priors. This is because Planck data appear to favor a higher matter
density and lower Hubble constant, in tension with most of the other current
cosmological data sets. Adding Planck distance priors to current data leads to
a marginal inconsistency with a cosmological constant in a flat universe.


title:
Genomic and phenotypic characterisation of a wild Medaka population:
  Establishing an isogenic population genetic resource in fish

abstract:
  Background Oryzias latipes (Medaka) has been established as a vertebrate
genetic model for over a century, and has recently been rediscovered outside
its native Japan. The power of new sequencing methods now makes it possible to
reinvigorate Medaka genetics, in particular by establishing a near-isogenic
panel derived from a single wild population. Results Here we characterise the
genomes of wild Medaka catches obtained from a single Southern Japanese
population in Kiyosu as a precursor for the establishment of a near isogenic
panel of wild lines. The population is free of significant detrimental
population structure, and has advantageous linkage disequilibrium properties
suitable for establishment of the proposed panel. Analysis of morphometric
traits in five representative inbred strains suggests phenotypic mapping will
be feasible in the panel. In addition high throughput genome sequencing of
these Medaka strains confirms their evolutionary relationships on lines of
geographic separation and provides further evidence that there has been little
significant interbreeding between the Southern and Northern Medaka population
since the Southern/Northern population split. The sequence data suggest that
the Southern Japanese Medaka existed as a larger older population which went
through a relatively recent bottleneck around 10,000 years ago. In addition we
detect patterns of recent positive selection in the Southern population.
Conclusions These data indicate that the genetic structure of the Kiyosu Medaka
samples are suitable for the establishment of a vertebrate near isogenic panel
and therefore inbreeding of 200 lines based on this population has commenced.
Progress of this project can be tracked at
http://www.ebi.ac.uk/birney-srv/medaka-ref-panel


title:
Dependence of the microwave surface resistance of superconducting
  niobium on the magnitude of the rf field

abstract:
  Utilizing difference in temperature dependencies we decoupled BCS and
residual components of the microwave surface resistance of superconducting
niobium at all rf fields up to $B_\mathrm{rf}\sim110$ mT. We reveal that the
residual resistance decreases with field at $B_\mathrm{rf} \lesssim$ 40 mT and
strongly increases in chemically treated niobium at $B_\mathrm{rf} > 80$ mT. We
find that BCS surface resistance is weakly dependent on field in the clean
limit, whereas a strong and peculiar field dependence emerges after
$120^\circ$C vacuum baking.


title: A Multiscale Sub-linear Time Fourier Algorithm for Noisy Data

abstract:
  We extend the recent sparse Fourier transform algorithm of (Lawlor,
Christlieb, and Wang, 2013) to the noisy setting, in which a signal of
bandwidth N is given as a superposition of k << N frequencies and additive
noise. We present two such extensions, the second of which exhibits a novel
form of error-correction in its frequency estimation not unlike that of the
beta-encoders in analog-to-digital conversion (Daubechies et al, 2006). The
algorithm runs in time O(k log(k) log(N/k)) on average, provided the noise is
not overwhelming. The error-correction property allows the algorithm to
outperform FFTW, a highly optimized software package for computing the full
discrete Fourier transform, over a wide range of sparsity and noise values, and
is to the best of our knowledge novel in the sparse Fourier transform context.


title:
Searches for violation of lepton flavour and baryon number in tau lepton
  decays at LHCb

abstract:
  Searches for the lepton flavour violating decay $\tau^-\rightarrow
\mu^-\mu^+\mu^-$ and the lepton flavour and baryon number violating decays
$\tau^-\rightarrow \bar{p}\mu^+\mu^-$ and $\tau^-\rightarrow p\mu^-\mu^-$ have
been carried out using proton-proton collision data, corresponding to an
integrated luminosity of 1.0 fb$^{-1}$, taken by the LHCb experiment at
$\sqrt{s} = 7$ TeV. No evidence has been found for any signal, and limits have
been set at 90% confidence level on the branching fractions: $\cal
B(\tau^-\rightarrow \mu^-\mu^+\mu^-) < 8.0 \times 10^{-8}$, $\cal
B(\tau^-\rightarrow \bar{p}\mu^+\mu^-) < 3.3 \times 10^{-7}$ and $\cal
B(\tau^-\rightarrow p\mu^-\mu^-) < 4.4 \times 10^{-7}$. The results for the
$\tau^-\rightarrow \bar{p}\mu^+\mu^-$ and $\tau^-\rightarrow p\mu^-\mu^-$ decay
modes represent the first direct experimental limits on these channels.


title: Leaderless deterministic chemical reaction networks

abstract:
  This paper answers an open question of Chen, Doty, and Soloveichik [1], who
showed that a function f:N^k --> N^l is deterministically computable by a
stochastic chemical reaction network (CRN) if and only if the graph of f is a
semilinear subset of N^{k+l}. That construction crucially used "leaders": the
ability to start in an initial configuration with constant but non-zero counts
of species other than the k species X_1,...,X_k representing the input to the
function f. The authors asked whether deterministic CRNs without a leader
retain the same power.
  We answer this question affirmatively, showing that every semilinear function
is deterministically computable by a CRN whose initial configuration contains
only the input species X_1,...,X_k, and zero counts of every other species. We
show that this CRN completes in expected time O(n), where n is the total number
of input molecules. This time bound is slower than the O(log^5 n) achieved in
[1], but faster than the O(n log n) achieved by the direct construction of [1]
(Theorem 4.1 in the latest online version of [1]), since the fast construction
of that paper (Theorem 4.4) relied heavily on the use of a fast, error-prone
CRN that computes arbitrary computable functions, and which crucially uses a
leader.


title: Sentiment Analysis : A Literature Survey

abstract:
  Our day-to-day life has always been influenced by what people think. Ideas
and opinions of others have always affected our own opinions. The explosion of
Web 2.0 has led to increased activity in Podcasting, Blogging, Tagging,
Contributing to RSS, Social Bookmarking, and Social Networking. As a result
there has been an eruption of interest in people to mine these vast resources
of data for opinions. Sentiment Analysis or Opinion Mining is the computational
treatment of opinions, sentiments and subjectivity of text. In this report, we
take a look at the various challenges and applications of Sentiment Analysis.
We will discuss in details various approaches to perform a computational
treatment of sentiments and opinions. Various supervised or data-driven
techniques to SA like Na\"ive Byes, Maximum Entropy, SVM, and Voted Perceptrons
will be discussed and their strengths and drawbacks will be touched upon. We
will also see a new dimension of analyzing sentiments by Cognitive Psychology
mainly through the work of Janyce Wiebe, where we will see ways to detect
subjectivity, perspective in narrative and understanding the discourse
structure. We will also study some specific topics in Sentiment Analysis and
the contemporary works in those areas.


title:
Determining Heating Rates in Reconnection Formed Flare Loops of the M8.0
  Flare on 2005 May 13

abstract:
  We analyze and model an M8.0 flare on 2005 May 13 observed by TRACE and
RHESSI to determine the energy release rate from magnetic reconnection that
forms and heats numerous flare loops. The flare exhibits two ribbons in UV 1600
{\AA} emission. Analysis shows that the UV light curve at each flaring pixel
rises impulsively within a few minutes, and decays slowly with a timescale >10
min. Since the lower atmosphere (transition region and chromosphere) responds
to energy deposit nearly instantaneously, the rapid UV brightening is thought
to reflect the energy release process in the newly formed flare loop rooted at
the footpoint. We utilize spatially resolved (down to 1 arcsec) UV light curves
and thick-target hard X-ray emission to construct heating functions of a few
thousand flare loops anchored at UV foot points, and compute plasma evolution
in these loops using the EBTEL model. The modeled coronal temperatures and
densities of these flare loops are used to calculate synthetic soft X-ray
spectra and light curves, which compare favorably with those observed by RHESSI
and GOES/XRS. The time-dependent transition region DEM for each loop during its
decay phase is also computed with a simplified model and used to calculate the
optically-thin C IV line emission, which dominates the UV 1600 {\AA} bandpass
during the flare. The computed C IV line emission decays at the same rate as
observed. This study presents a method to constrain heating of
reconnection-formed flare loops using all available observables independently,
and provides insight into the physics of energy release and plasma heating
during the flare. With this method, the lower limit of the total energy used to
heat the flare loops in this event is estimated to be 1.22e31 ergs, of which
only 1.9e30 ergs is carried by beam-driven upflows during the impulsive phase,
suggesting that the coronal plasmas are predominantly heated in situ.


title: Mass Spectrum of Heavy Quarkonium Hybrids

abstract:
  We have extended the calculation of the correlation functions of heavy
quarkonium hybrid operators with various $J^{PC}$ quantum numbers to include
QCD condensates up to dimension six. In contrast to previous analyses which
were unable to optimize the QCD sum-rules for certain $J^{PC}$, recent work has
shown that inclusion of dimension six condensates stabilizes the hybrid
sum-rules and permits reliable mass predictions. In this work we have
investigated the effects of the dimension six condensates on the remaining
channels. After performing the QCD sum-rule analysis, we update the mass
spectra of charmonium and bottomonium hybrids with exotic and non-exotic
quantum numbers. We identify that the negative-parity states with $J^{PC}=(0,
1, 2)^{-+}, 1^{--}$ form the lightest hybrid supermultiplet while the
positive-parity states with $J^{PC}=(0, 1)^{+-}, (0, 1, 2)^{++}$ belong to a
heavier hybrid supermultiplet, confirming the supermultiplet structure found in
other approaches. The hybrid with $J^{PC}=0^{--}$ has a much higher mass which
may suggest a different excitation of the gluonic field compared to other
channels. In agreement with previous results, we find that the $J^{PC}=1^{++}$
charmonium hybrid is substantially heavier than the X(3872), which seems to
preclude a pure charmonium hybrid interpretation for this state.


title:
Origins of power-law degree distribution in the heterogeneity of human
  activity in social networks

abstract:
  The probability distribution of number of ties of an individual in a social
network follows a scale-free power-law. However, how this distribution arises
has not been conclusively demonstrated in direct analyses of people's actions
in social networks. Here, we perform a causal inference analysis and find an
underlying cause for this phenomenon. Our analysis indicates that heavy-tailed
degree distribution is causally determined by similarly skewed distribution of
human activity. Specifically, the degree of an individual is entirely random -
following a "maximum entropy attachment" model - except for its mean value
which depends deterministically on the volume of the users' activity. This
relation cannot be explained by interactive models, like preferential
attachment, since the observed actions are not likely to be caused by
interactions with other people.


title:
Investigating Randomly Generated Adjacency Matrices For Their Use In
  Modeling Wireless Topologies

abstract:
  Generation of realistic topologies plays an important role in determining the
accuracy and validity of simulation studies. This study presents a discussion
to justify why, and how often randomly generated adjacency matrices may not not
conform to wireless topologies in the physical world. Specifically, it shows
through analysis and random trials that, more than 90% of times, a randomly
generated adjacency matrix will not conform to a valid wireless topology, when
it has more than 3 nodes. By showing that node triplets in the adjacency graph
need to adhere to rules of a geometric vector space, the study shows that the
number of randomly chosen node triplets failing consistency checks grow at the
order of O(base^3), where base is the granularity of the distance metric.
Further, the study models and presents a probability estimate with which any
randomly generated adjacency matrix would fail realization. This information
could be used to design simpler algorithms for generating k-connected wireless
topologies.


title:
Overspend? Late? Failure? What the Data Say About IT Project Risk in the
  Public Sector

abstract:
  Implementing large-scale information and communication technology (IT)
projects carries large risks and easily might disrupt operations, waste
taxpayers' money, and create negative publicity. Because of the high risks it
is important that government leaders manage the attendant risks. We analysed a
sample of 1,355 public sector IT projects. The sample included large-scale
projects, on average the actual expenditure was $130 million and the average
duration was 35 months. Our findings showed that the typical project had no
cost overruns and took on average 24% longer than initially expected. However,
comparing the risk distribution with the normative model of a thin-tailed
distribution, projects' actual costs should fall within -30% and +25% of the
budget in nearly 99 out of 100 projects. The data showed, however, that a
staggering 18% of all projects are outliers with cost overruns >25%. Tests
showed that the risk of outliers is even higher for standard software (24%) as
well as in certain project types, e.g., data management (41%), office
management (23%), eGovernment (21%) and management information systems (20%).
Analysis showed also that projects duration adds risk: every additional year of
project duration increases the average cost risk by 4.2 percentage points.
Lastly, we suggest four solutions that public sector organization can take: (1)
benchmark your organization to know where you are, (2) de-bias your IT project
decision-making, (3) reduce the complexities of your IT projects, and (4)
develop Masterbuilders to learn from the best in the field.


title:
Non-maximal \theta_{23}, large \theta_{13} and tri-bimaximal \theta_{12}
  via quark-lepton complementarity at next-to-leading order

abstract:
  We show that the next-to-leading order corrections in the quark-lepton
complementarity are important to explain the observed pattern of neutrino
mixing. In particular, the next-to-leading order corrections 1) lead to a
deviation of \theta_{23} from maximal mixing, 2) reduce the predicted value of
$\sin^2 2\theta_{13}$ by 9.8%, 3) provide the same value of $\sin^2
\theta_{12}$ as that of the tri-bimaximal mixing. This is shown by calculating
$\sin^2 2\theta_{ij} (i,j=1,2,3)$ to ${\cal O}(\lambda^6)$ in the framework in
which the product of the CKM and PMNS matrices is bimaximal.


title:
Essential connectedness and the rigidity problem for Gaussian
  symmetrization

abstract:
  We provide a geometric characterization of rigidity of equality cases in
Ehrhard's symmetrization inequality for Gaussian perimeter. This condition is
formulated in terms of a new measure-theoretic notion of connectedness for
Borel sets, inspired by Federer's definition of indecomposable current.


title:
Optimizing electronic structure and quantum transport at the
  graphene-Si(111) interface: An ab-initio density-functional study

abstract:
  We use ab initio density functional calculations to determine the interaction
of a graphene monolayer with the Si(111) surface. We found that graphene forms
strong bonds to the bare substrate and accommodates the 12% lattice mismatch by
forming a wavy structure consisting of free-standing conductive ridges that are
connected by ribbon-shaped regions of graphene, which bond covalently to the
substrate. We perform quantum transport calculations for different geometries
to study changes in the transport properties of graphene introduced by the wavy
structure and bonding to the Si substrate. Our results suggest that wavy
graphene combines high mobility along the ridges with efficient carrier
injection into Si in the contact regions.