title:
Populations of rotating stars II. Rapid rotators and their link to
  Be-type stars

abstract:
  Even though it is broadly accepted that single Be stars are rapidly rotating
stars surrounded by a flat rotating circumstellar disk, there is still a debate
about how fast these stars rotate and also about the mechanisms involved in the
angular-momentum and mass input in the disk. We study the properties of stars
that rotate near their critical-rotation rate and investigate the properties of
the disks formed by equatorial mass ejections. We used the most recent Geneva
stellar evolutionary tracks for rapidly rotating stars that reach the critical
limit and used a simple model for the disk structure. We obtain that for a 9
Msun star at solar metallicity, the minimum average velocity during the Main
Sequence phase to reach the critical velocity is around 330 km/s, whereas it
would be 390 km/s at the metallicity of the Small Magellanic Cloud (SMC). Red
giants or supergiants originating from very rapid rotators rotate six times
faster and show N/C ratios three times higher than those originating from
slowly rotating stars. This difference becomes stronger at lower metallicity.
It might therefore be very interesting to study the red giants in clusters that
show a large number of Be stars on the MS band. On the basis of our single-star
models, we show that the observed Be-star fraction with cluster age is
compatible with the existence of a temperature-dependent lower limit in the
velocity rate required for a star to become a Be star. The mass, extension, and
diffusion time of the disks produced when the star is losing mass at the
critical velocity, obtained from simple parametrized expressions, are not too
far from those estimated for disks around Be-type stars. At a given
metallicity, the mass and the extension of the disk increase with the initial
mass and with age on the MS phase. Denser disks are expected in low-metallicity
regions.


title:
Asymptotic behaviour and the Nahm transform of doubly periodic
  instantons with square integrable curvature

abstract:
  We study the asymptotic behaviour of doubly periodic instantons with
square-integrable curvature. Then, we establish the equivalence given by the
Nahm transform between the doubly periodic instantons with square integrable
curvature and the wild harmonic bundles on the dual torus.


title:
State estimation under non-Gaussian Levy noise: A modified Kalman
  filtering method

abstract:
  The Kalman filter is extensively used for state estimation for linear systems
under Gaussian noise. When non-Gaussian L\'evy noise is present, the
conventional Kalman filter may fail to be effective due to the fact that the
non-Gaussian L\'evy noise may have infinite variance. A modified Kalman filter
for linear systems with non-Gaussian L\'evy noise is devised. It works
effectively with reasonable computational cost. Simulation results are
presented to illustrate this non-Gaussian filtering method.

categories: math.DS cs.IT cs.LG math.IT math.PR stat.ML


title:
Photoionization modeling of oxygen K absorption in the interstellar
  medium:the Chandra grating spectra of XTE J1817-330

abstract:
  We present detailed analyses of oxygen K absorption in the interstellar
medium (ISM) using four high-resolution Chandra spectra towards the X-ray
low-mass binary XTE J1817-330. The 11-25 A broadband is described with a simple
absorption model that takes into account the pileup effect and results in an
estimate of the hydrogen column density. The oxygen K-edge region (21-25 A) is
fitted with the physical warmabs model, which is based on a photoionization
model grid generated with the xstar code with the most up-to-date atomic
database. This approach allows a benchmark of the atomic data which involves
wavelength shifts of both the K lines and photoionization cross sections in
order to fit the observed spectra accurately. As a result we obtain: a column
density of N(H)=1.38+/-0.01\times 10^21 cm^-2; ionization parameter of
log(xi)=-2.70+/-0.023; oxygen abundance of A(O)= 0.689^{+0.015}_{-0.010}; and
ionization fractions of OI/O = 0.911, OII/O = 0.077, and OIII/O = 0.012 that
are in good agreement with previous studies. Since the oxygen abundance in
warmabs is given relative to the solar standard of Grevesse et al. (1998), a
rescaling with the revision by Asplund et al. (2009) yields
A(O)=0.952^{+0.020}_{-0.013}, a value close to solar that reinforces the new
standard. We identify several atomic absorption lines Kalpha, Kbeta, and Kgamma
in OI and OII; and Kalpha in OIII, OVI, and OVII - last two probably residing
in the neighborhood of the source rather than in the ISM. This is the first
firm detection of oxygen K resonances with principal quantum numbers n>2
associated to ISM cold absorption.


title:
A Comparison of the Velocity Parameters of SiO v=1, J=1-0 and J=2-1
  Maser Emission in Long Period Variables

abstract:
  We present an analysis of velocity parameters derived from multi-epoch
observations of the SiO maser spectra of 47 long period variables (LPVs). The
velocity parameters are important to inform and constrain theoretical models of
SiO maser emission and to extract information on binary orbits. Mira and R
Aquarii (R Aqr) are two known binaries included in the program. The 47 LPVs are
among 121 sources of the Australia Telescope National Facility (ATNF) Mopra
telescope's monitoring program. Observations were carried out several times a
year between 2008 and 2012 and are continuing. The SiO spectra are from the
v=1, J=1-0 (43.122 GHz; hereafter J10) and the v=1, J=2-1 (86.2434 GHz;
hereafter J21) transitions. For 41 of the 47 LPVs we observed both transitions
nearly simultaneously in 457 observations. We have determined and compared the
velocity centroids (VCs) and velocity ranges of emission (VRs) suffixed as
above (10 and 21) for the two transitions - VC10, VC21, VR10, and VR21. The VCs
of the two transitions are, on average, within 0.13 km s-1 of each other but
are sometimes separated by a few km s-1. The VC10s are, on average, slightly
more positive than the VC21s. The values of the VCs in the two transitions have
been compared to justify using both of these transitions to extract binary star
orbital parameters. The arithmetic mean VR10 derived from 635 observations of
47 sources is 6.4 km s-1 with a standard deviation of 3.4 km s-1 while the mean
VR21 derived from 485 observations of 41 sources is 4.2 km s-1 with a standard
deviation of 2.8 km s-1. The number of occurrences of VR10 and VR21versus
velocity range have different distributions. The differences in the VRs
indicate that the J21 and J10 emissions arise from dynamically different
regions of the circumstellar environment.


title: Fossil diatoms in a new carbonaceous meteorite

abstract:
  We report the discovery for the first time of diatom frustules in a
carbonaceous meteorite that fell in the North Central Province of Sri Lanka on
29 December 2012. Contamination is excluded by the circumstance that the
elemental abundances within the structures match closely with those of the
surrounding matrix. There is also evidence of structures morphologically
similar to red rain cells that may have contributed to the episode of red rain
that followed within days of the meteorite fall. The new data on fossil diatoms
provide strong evidence to support the theory of cometary panspermia.


title:
Starch metabolism and antiflorigenic signals modulate the
  juvenile-to-adult phase transition in Arabidopsis

abstract:
  The physiology and genetics underlying juvenility is poorly understood. Here
we exploit Arabidopsis as a system to understand the mechanisms that regulate
floral incompetence during juvenility. Using an experimental assay that allows
the length of juvenility to be estimated, and mutants impaired in different
pathways, we show that multiple inputs influence juvenility. Juvenile phase
lengths of wild type (WT) accessions Col-0, Ler-0 and Ws-4 are shown to differ,
with Col-0 having the shortest and Ws-4 the longest length. Plants defective in
sugar signalling [gin1-1, gin2-1, gin6 (abi4)] and floral repressor mutants
[hst1, tfl1, tfl2 (lhp1)] showed shortened juvenile phase lengths, compared to
their respective WTs. Mutants defective in starch anabolism (adg1-1, pgm1) and
catabolism (sex1, sex4, bam3) showed prolonged juvenile phase lengths compared
to Col-0. Examination of diurnal metabolite changes in adg1-1 and sex1 mutants
indicates that their altered juvenile phase length may be due to lack of starch
turnover, which influences carbohydrate availability. In this article we
propose a model in which a variety of signals including floral activators and
repressors modulate the juvenile-to-adult phase transition. The role of
carbohydrates may be in their capacity as nutrients, osmotic regulators,
signalling molecules and/ or through their interaction with phytohormonal
networks.


title:
Center-stable manifold of the ground state in the energy space for the
  critical wave equation

abstract:
  We construct a center-stable manifold of the ground state solitons in the
energy space for the critical wave equation without imposing any symmetry, as
the dynamical threshold between scattering and blow-up, and also as a
collection of solutions which stay close to the ground states. Up to energy
slightly above the ground state, this completes the 9-set classification of the
global dynamics in our previous paper. We can also extend the manifold to
arbitrary energy size by adding large radiation. The manifold contains all the
solutions scattering to the ground state solitons, and also some of those
blowing up in finite time by concentration of the ground states.


title: Discovery of a Binary Brown Dwarf at 2 Parsecs from the Sun

abstract:
  I am using multi-epoch astrometry from the Wide-field Infrared Survey
Explorer (WISE) to search for new members of the solar neighborhood via their
high proper motions. Through this work, I have identified WISE
J104915.57-531906.1 as a high proper motion object and have found additional
detections in images from the Digitized Sky Survey, the Two Micron All-Sky
Survey, and the Deep Near-Infrared Survey of the Southern Sky. I have measured
a parallax of 0.496+/-0.037" (2.0+/-0.15 pc) from the astrometry in these
surveys, making WISE J104915.57-531906.1 the third closest system to the Sun.
During spectroscopic observations with GMOS at Gemini Observatory, an i-band
acquisition image resolved it as a 1.5" (3 AU) binary. A spectrum was collected
for the primary, which I classify as L8+/-1. The secondary is probably near the
L/T transition as well given that it is only modestly fainter than the primary
(delta i=0.45 mag).


title: RGE of the Higgs mass in the context of the SM

abstract:
  Renormalization group equation (RGE) of the Higgs mass up to one-loop order
is derived in $R_\xi$ gauge with dimensional regularization method (DREG) base
on MS (or $\bar{\rm{MS}}$) scheme. Scale-dependent properties of the Higgs mass
up to two-loop level are investigated. The result gives the positive Higgs mass
up to energy scale around the Planck scale. While following the vacuum
stability argument, the Higgs mass need to be negative above the energy scale
$10^{10}$ GeV for $M_{t}=173.3$ GeV. The conflict is induced by the
renormalization of vacuum energy value(VEV).


title: A Liouville Theorem for the Complex Monge-Amp\`ere Equation

abstract:
  In this note, we derive a Liouville theorem for the complex Monge-Amp\`ere
equation. Our result states that if the global solution $u$ of the complex
Monge-Amp\`ere equation with constant right-hand side differs from a quadratic
polynomial solution by $o(\abs{x}^2)$ at infinity, then $u$ is a quadratic
polynomial.


title: Injectivity theorems

abstract:
  We prove some injectivity theorems. Our proof depends on the theory of mixed
Hodge structures on cohomology groups with compact support. Our injectivity
theorems would play crucial roles in the minimal model theory for
higher-dimensional algebraic varieties. We also treat some applications.


title: The Kadison-Singer problem in discrepancy theory, II

abstract:
  We apply Srivastava's spectral sparsification technique to a vector balancing
version of the Kadison-Singer problem. The result is a one-sided version of the
conjectured solution.


title:
Topology, rigid cosymmetries and linearization instability in higher
  gauge theories

abstract:
  We consider a class of non-linear PDE systems, whose equations possess
Noether identities (the equations are redundant), including non-variational
systems (not coming from Lagrangian field theories), where Noether identities
and infinitesimal gauge transformations need not be in bijection. We also
include theories with higher stage Noether identities, known as higher gauge
theories (if they are variational). Some of these systems are known to exhibit
linearization instabilities: there exist exact background solutions about which
a linearized solution is extendable to a family of exact solutions only if some
non-linear obstruction functionals vanish. We give a general, geometric
classification of a class of these linearization obstructions, which includes
as special cases all known ones for relativistic field theories (vacuum
Einstein, Yang-Mills, classical N=1 supergravity, etc.). Our classification
shows that obstructions arise due to the simultaneous presence of rigid
cosymmetries (generalized Killing condition) and non-trivial de Rham cohomology
classes (spacetime topology). The classification relies on a careful analysis
of the cohomologies of the on-shell Noether complex (consistent deformations),
adjoint Noether complex (rigid cosymmetries) and variational bicomplex
(conserved currents). An intermediate result also gives a criterion for
identifying non-linearities that do not lead to linearization instabilities.


title:
Superconductor-Nanowire Devices from Tunneling to the Multichannel
  Regime: Zero-Bias Oscillations and Magnetoconductance Crossover

abstract:
  We present transport measurements in superconductor-nanowire devices with a
gated constriction forming a quantum point contact. Zero-bias features in
tunneling spectroscopy appear at finite magnetic fields, and oscillate in
amplitude and split away from zero bias as a function of magnetic field and
gate voltage. A crossover in magnetoconductance is observed: Magnetic fields
above ~ 0.5 T enhance conductance in the low-conductance (tunneling) regime but
suppress conductance in the high-conductance (multichannel) regime. We consider
these results in the context of Majorana zero modes as well as alternatives,
including Kondo effect and analogs of 0.7 structure in a disordered nanowire.


title: Exotic Ising dynamics in a Bose-Hubbard model

abstract:
  We explore the dynamical properties of a one-dimensional Bose-Hubbard model,
where two bosonic species interact via Feshbach resonance. We focus on the
region in the phase diagram which is described by an effective, low-energy
ferromagnetic Ising model in both transverse and longitudinal fields. In this
regime, we numerically calculate the dynamical structure factor of the
Bose-Hubbard model using the time-evolving block decimation method. In the
ferromagnetic phase, we observe both the continuum of excitations and the bound
states in the presence of a longitudinal field. Near the Ising critical point,
we observe the celebrated E8 mass spectrum in the excited states. We also point
out possible measurements which could be used to detect these excitations in an
optical lattice experiment.


title:
Finite-time Stabilization of Circular Formations using Bearing-only
  Measurements

abstract:
  This paper studies decentralized formation control of multiple vehicles when
each vehicle can only measure the local bearings of their neighbors by using
bearing-only sensors. Since the inter-vehicle distance cannot be measured, the
target formation involves no distance constraints. More specifically, the
target formation considered in this paper is an angle-constrained circular
formation, where each vehicle has exactly two neighbors and the angle at each
vehicle subtended by its two neighbors is pre-specified. To stabilize the
target formation, we propose a discontinuous control law that only requires the
sign information of the angle errors. Due to the discontinuity of the proposed
control law, the stability of the closed-loop system is analyzed by employing a
locally Lipschitz Lyapunov function and nonsmooth analysis tools. We prove that
the target formation is locally finite-time stable with collision avoidance
guaranteed. The evolution of the vehicle positions in the plane is also
characterized.


title: Kerr-Like Phantom Wormhole

abstract:
  In this work we study a Kerr-like wormhole with phantom matter as source. It
has three parameters: mass, angular momentum and scalar field charge. This
wormhole has a naked ring singularity, other wise it is regular everywhere. The
mean feature of this wormhole is that the mouth of the throat lie on a sphere
of the same radius as the ring singularity an avoids any observer to see or to
reach the singularity, it behaves like an anti-horizon. We analyse the
geodesics of the wormhole and find that an observer can go through the
geodesics without troubles, but the equator presents an infinity potential
barrier which avoids to reach the throat. From an analysis of the Riemann
tensor we obtain that the tidal forces permits the wormhole to be traversable
for an observer like a human being.


title:
RNA-Seq Mapping Errors When Using Incomplete Reference Transcriptomes of
  Vertebrates

abstract:
  Whole transcriptome sequencing is increasingly being used as a functional
genomics tool to study non- model organisms. However, when the reference
transcriptome used to calculate differential expression is incomplete,
significant error in the inferred expression levels can result. In this study,
we use simulated reads generated from real transcriptomes to determine the
accuracy of read mapping, and measure the error resulting from using an
incomplete transcriptome. We show that the two primary sources of count- ing
error are 1) alternative splice variants that share reads and 2) missing
transcripts from the reference. Alternative splice variants increase the false
positive rate of mapping while incomplete reference tran- scriptomes decrease
the true positive rate, leading to inaccurate transcript expression levels.
Grouping transcripts by gene or read sharing (similar to mapping to a reference
genome) significantly decreases false positives, but only by improving the
reference transcriptome itself can the missing transcript problem be addressed.
We also demonstrate that employing different mapping software does not yield
substantial increases in accuracy on simulated data. Finally, we show that read
lengths or insert sizes must increase past 1kb to resolve mapping ambiguity.


title:
The Cost of Deterministic, Adaptive, Automatic Algorithms: Cones, Not
  Balls

abstract:
  Automatic numerical algorithms attempt to provide approximate solutions that
differ from exact solutions by no more than a user-specified error tolerance.
The computational cost is often determined \emph{adaptively} by the algorithm
based on the function values sampled. While adaptive, automatic algorithms are
widely used in practice, most lack \emph{guarantees}, i.e., conditions on input
functions that ensure that the error tolerance is met.
  This article establishes a framework for guaranteed, adaptive, automatic
algorithms. Sufficient conditions for success and two-sided bounds on the
computational cost are provided in Theorems \ref{TwoStageDetermThm} and
\ref{MultiStageThm}. Lower bounds on the complexity of the problem are given in
Theorem \ref{complowbd}, and conditions under which the proposed algorithms
have optimal order are given in Corollary \ref{optimcor}. These general
theorems are illustrated for univariate numerical integration and function
recovery via adaptive algorithms based on linear splines.
  The key to these adaptive algorithms is performing the analysis for
\emph{cones} of input functions rather than balls. Cones provide a setting
where adaption may be beneficial.


title: Witness of unsatisfiability for a random 3-satisfiability formula

abstract:
  The random 3-satisfiability (3-SAT) problem is in the unsatisfiable (UNSAT)
phase when the clause density $\alpha$ exceeds a critical value $\alpha_s
\approx 4.267$. However, rigorously proving the unsatisfiability of a given
large 3-SAT instance is extremely difficult. In this paper we apply the
mean-field theory of statistical physics to the unsatisfiability problem, and
show that a specific type of UNSAT witnesses (Feige-Kim-Ofek witnesses) can in
principle be constructed when the clause density $\alpha > 19$. We then
construct Feige-Kim-Ofek witnesses for single 3-SAT instances through a simple
random sampling algorithm and a focused local search algorithm. The random
sampling algorithm works only when $\alpha$ scales at least linearly with the
variable number $N$, but the focused local search algorithm works for clause
densty $\alpha > c N^{b}$ with $b \approx 0.59$ and prefactor $c \approx 8$.
The exponent $b$ can be further decreased by enlarging the single parameter $S$
of the focused local search algorithm.


title: A Bayesian Approach to Data Fusion in Sensor Networks

abstract:
  In this paper, we address the fusion problem in wireless sensor networks,
where the cross-correlation between the estimates is unknown. To solve the
problem within the Bayesian framework, we assume that the covariance matrix has
a prior distribution. We also assume that we know the covariance of each
estimate, i.e., the diagonal block of the entire covariance matrix (of the
random vector consisting of the two estimates). We then derive the conditional
distribution of the off-diagonal blocks, which is the cross-correlation of our
interest. We show that when there are two nodes, the conditional distribution
happens to be the inverted matrix variate $t$-distribution, from which we can
readily sample. For more than two nodes, the conditional distribution is no
longer the inverted matrix variate $t$-distribution. But we show that we can
decompose it into several sampling problems, each of which is the inverted
matrix variate $t$-distribution and therefore we can still sample from it.
Since we can sample from this distribution, it enables us to use the Monte
Carlo method to compute the minimum mean square error estimate for the fusion
problem. We use two models to generate experiment data and demonstrate the
generality of our method. Simulation results show that the proposed method
works better than the popular covariance intersection method.


title: Properties of Near-Sun Asteroids

abstract:
  Asteroids near the Sun can attain equilibrium temperatures sufficient to
induce surface modification from thermal fracture, desiccation and
decomposition of hydrated silicates. We present optical observations of nine
asteroids with perihelia <0.25 AU (sub-solar temperatures greater than/equal to
800 K) taken to search for evidence of thermal modification. We find that the
broadband colors of these objects are diverse but statistically
indistinguishable from those of planet-crossing asteroids having perihelia near
1 AU. Furthermore, images of these bodies taken away from perihelion show no
evidence for on-going mass-loss (model-dependent limits roughly less than/equal
to 1 kg /s) that might result from thermal disintegration of the surface. We
conclude that, while thermal modification may be an important process in the
decay of near-Sun asteroids and in the production of debris, our new data
provide no evidence for it.


title: Fast Arithmetic in Algorithmic Self-Assembly

abstract:
  In this paper we consider the time complexity of computing the sum and
product of two $n$-bit numbers within the tile self-assembly model. The
(abstract) tile assembly model is a mathematical model of self-assembly in
which system components are square tiles with different glue types assigned to
tile edges. Assembly is driven by the attachment of singleton tiles to a
growing seed assembly when the net force of glue attraction for a tile exceeds
some fixed threshold. Within this frame work, we examine the time complexity of
computing the sum or product of 2 n-bit numbers, where the input numbers are
encoded in an initial seed assembly, and the output is encoded in the final,
terminal assembly of the system. We show that the problems of addition and
multiplication have worst case lower bounds of $\Omega(\sqrt{n})$ in 2D
assembly, and $\Omega(\sqrt[3]{n})$ in 3D assembly. In the case of addition, we
design algorithms for both 2D and 3D that meet this bound with worst case run
times of $O(\sqrt{n})$ and $O(\sqrt[3]{n})$ respectively, which beats the
previous best known upper bound of O(n). Further, we consider average case
complexity of addition over uniformly distributed n-bit strings and show how to
achieve $O(\log n)$ average case time with a simultaneous $O(\sqrt{n})$ worst
case run time in 2D. For multiplication, we present an $O(n^{5/6})$ time
multiplication algorithm which works in 3D, which beats the previous best known
upper bound of O(n). As additional evidence for the speed of our algorithms, we
implement our addition algorithms, along with the simpler O(n) time addition
algorithm, into a probabilistic run-time simulator and compare the timing
results.


title: Linear NDCG and Pair-wise Loss

abstract:
  Linear NDCG is used for measuring the performance of the Web content quality
assessment in ECML/PKDD Discovery Challenge 2010. In this paper, we will prove
that the DCG error equals a new pair-wise loss.


title: Diffusive stability of Turing patterns via normal forms

abstract:
  We investigate dynamics near Turing patterns in reaction-diffusion systems
posed on the real line. Linear analysis predicts diffusive decay of small
perturbations. We construct a "normal form" coordinate system near such Turing
patterns which exhibits an approximate discrete conservation law. The key
ingredients to the normal form is a conjugation of the reaction-diffusion
system on the real line to a lattice dynamical system. At each lattice site, we
decompose perturbations into neutral phase shifts and normal decaying
components. As an application of our normal form construction, we prove
nonlinear stability of Turing patterns with respect to perturbations that are
small in $L^1\cap L^\infty$, with sharp rates.


title:
The Dirichlet Problem for the Prescribed Ricci Curvature Equation on
  Cohomogeneity One Manifolds

abstract:
  Let $M$ be a domain enclosed between two principal orbits on a cohomogeneity
one manifold $M_1$. Suppose $T$ and $R$ are symmetric invariant (0,2)-tensor
fields on $M$ and $\partial M$, respectively. The paper studies the prescribed
Ricci curvature equation $\mathrm{Ric}(G)=T$ for a Riemannian metric $G$ on $M$
subject to the boundary condition $G_{\partial M}=R$ (the notation $G_{\partial
M}$ here stands for the metric induced by $G$ on $\partial M$). Imposing a
standard assumption on $M_1$, we describe a set of requirements on $T$ and $R$
that guarantee global and local solvability.


title: Orbital integrals and Dedekind zeta functions

abstract:
  Let F be a local non-archimedean field. We prove a formula relating orbital
integrals in GL(n,F) (for the unit Hecke function) and the generating series
counting ideals of a certain ring. Using this formula, we give an explicit
estimate for such orbital integrals. We also derive an analogous formula for
global fields, proving analytic properties of the Dedekind zeta function for
orders in global fields.


title:
Studying the elastic properties of nanocrystalline copper using a model
  of randomly packed uniform grains

abstract:
  We develop a new Voronoi protocol, which is a space tessellation method, to
generate fully dense (containing no voids) nanocrystalline models of copper
(Cu) with precise grain size control; we also perform uniaxial tensile tests
using molecular dynamical (MD) simulations to measure the elastic moduli of the
grain boundary and the grain interior components at 300 K. We find that the
grain boundary deforms more locally compared with the grain core region under
thermal vibrations and is elastically less stiff than the core component at
finite temperature. The elastic modulus of the grain boundary is lower than 30%
of that of the grain interior. Our results will aid in the development of more
accurate continuum models of nanocrystalline metals.


title: Robust Distributed Averaging in Networks

abstract:
  In this work, we consider two types of adversarial attacks on a network of
nodes seeking to reach consensus. The first type involves an adversary that is
capable of breaking a specific number of links at each time instant. In the
second attack, the adversary is capable of corrupting the values of the nodes
by adding a noise signal. In this latter case, we assume that the adversary is
constrained by a power budget. We consider the optimization problem of the
adversary and fully characterize its optimum strategy for each scenario.


title: Discrepancy bounds for uniformly ergodic Markov chain quasi-Monte Carlo

abstract:
  Markov chains can be used to generate samples whose distribution approximates
a given target distribution. The quality of the samples of such Markov chains
can be measured by the discrepancy between the empirical distribution of the
samples and the target distribution. We prove upper bounds on this discrepancy
under the assumption that the Markov chain is uniformly ergodic and the driver
sequence is deterministic rather than independent $U(0,1)$ random variables. In
particular, we show the existence of driver sequences for which the discrepancy
of the Markov chain from the target distribution with respect to certain test
sets converges with (almost) the usual Monte Carlo rate of $n^{-1/2}$.


title: Continuous and smooth envelopes of topological algebras

abstract:
  Since the time when the first optical instruments have been invented, an idea
that the visible image of an object under observation depends on tools of
observation became commonly assumed in physics. A way to formalize it in
mathematics is the construction that assigns to an arbitrary object $A$ in a
category $K$ its envelope $\text{Env}_\varPhi^\varOmega A$ in a given class of
morphisms (a class of representations) $\varOmega$ with respect to a given
class of morphisms (a class of observation tools) $\varPhi$. It turns out that
if we take a sufficiently wide category of topological algebras as $K$, then
each choice of the classes $\varOmega$ and $\varPhi$ defines a "projection of
functional analysis into geometry", and the standard "geometric disciplines",
like complex geometry, differential geometry and topology, become special cases
of this construction.
  This gives a formal scheme of "categorical construction of geometries" with
many interesting applications, in particular, "geometric generalizations of the
Pontryagin duality" (to the classes of non-commutative groups).
  In this paper we describe this scheme in topology and in differential
geometry.


title: High-Energy Emission from the Composite Supernova Remnant MSH 15-56

abstract:
  MSH 15-56 (G326.3-1.8) is a composite supernova remnant (SNR) that consists
of an SNR shell and a displaced pulsar wind nebula (PWN) in the radio. We
present XMM-Newton and Chandra X-ray observations of the remnant that reveal a
compact source at the tip of the radio PWN and complex structures that provide
evidence for mixing of the supernova (SN) ejecta with PWN material following a
reverse shock interaction. The X-ray spectra are well fitted by a non-thermal
power-law model whose photon index steepens with distance from the presumed
pulsar, and a thermal component with an average temperature of 0.55 keV. The
enhanced abundances of silicon and sulfur in some regions, and the similar
temperature and ionization timescale, suggest that much of the X-ray emission
can be attributed to SN ejecta that have either been heated by the reverse
shock or swept up by the PWN. We find one region with a lower temperature of
0.3 keV that appears to be in ionization equilibrium. Assuming the Sedov model,
we derive a number of SNR properties, including an age of 16,500 yr. Modeling
of the gamma-ray emission detected by Fermi shows that the emission may
originate from the reverse shock-crushed PWN.


title:
The SM extension with color-octet scalars: diphoton enhancement and
  global fit of LHC Higgs data

abstract:
  In light of the significant progress of the LHC to determine the properties
of the Higgs boson, we investigate the capability of the Manohar-Wise model in
explaining the Higgs data. This model extends the SM by one family of
color-octet and isospin-doublet scalars, and it can sizably alter the coupling
strengths of the Higgs boson with gluons and photons. We first examine the
current constraints on the model, which are from unitarity, the LHC searches
for the scalars and the electroweak precision data (EWPD).In implementing the
unitarity constraint, we use the properties of the SU(3) group to simplify the
calculation. Then in the allowed parameter space we perform a fit of the model,
using the latest ATLAS and CMS data, respectively. We find that the
Manohar-Wise model is able to explain the data with \chi^2 significantly
smaller than the SM value. We also find that the current Higgs data, especially
the ATLAS data, are very powerful in further constraining the parameter space
of the model. In particular, in order to explain the diphoton enhancement
reported by the ATLAS collaboration, the sign of the hgg coupling is usually
opposite to that in the SM.


title:
Water Maser Survey on AKARI and IRAS Sources: A Search for
  "Low-Velocity" Water Fountains

abstract:
  We present the results of a 22GHz H2O maser survey toward a new sample of AGB
and post-AGB star candidates. Most of the objects are selected for the first
time based on the AKARI data, which have high flux sensitivity in the
mid-infrared ranges. We aim at finding H2O maser sources in the transient phase
between the AGB and post-AGB stage of evolution, where the envelopes start to
develop large deviations from spherical symmetry. The observations were carried
out with the Effelsberg 100m radio telescope. Among 204 observed objects, 63
detections (36 new) were obtained. We found 4 objects which may be "water
fountain" sources (IRAS 15193+3132, IRAS 18056-1514, OH 16.3-3.0, and IRAS
18455+0448). They possess an H2O maser velocity coverage much smaller than
those in other known water fountains. However, the coverage is still larger
than that of the 1612MHz OH maser. It implies that there is an outflow with a
higher velocity than the envelope expansion velocity (typically <25 km/s),
meeting the criterion of the water fountain class. We suggest that these
candidates are possibly oxygen-rich late AGB or early post-AGB stars in a stage
of evolution immediately after the spherically symmetric AGB mass-loss has
ceased.


title:
Experimental quantum Zeno effect in NMR with entanglement-based
  measurement

abstract:
  We experimentally demonstrate a new dynamic fashion of quantum Zeno effect in
nuclear magnetic resonance systems. The frequent measurements are implemented
through quantum entanglement between the target qubit(s) and the measuring
qubit, which dynamically results from the unitary evolution of duration
$\tau_{m}$ due to dispersive-coupling. Experimental results testify the
presence of "the critical measurement time effect", that is, the quantum Zeno
effect does not occur when $\tau_{m}$ takes the some critical values, even if
the measurements are frequent enough. Moreover, we provide a first experimental
demonstration of an entanglement preservation mechanism based on such dynamic
quantum Zeno effect.


title: Two-parameter quantum algebras, canonical bases and categorifications

abstract:
  A theory of canonical basis for a two-parameter quantum algebra is developed
in parallel with the one in one-parameter case. A geometric construction of the
negative part of a two-parameter quantum algebra is given by using mixed
perverse sheaves and Deligne's weight theory based on Lusztig's work. A
categorification of the negative part of a two-parameter quantum algebra is
provided. A two-parameter quantum algebra is shown to be a two-cocycle
deformation, depending only on the second parameter, of its one-parameter
analogue.


title:
Quantum and Concept Combination, Entangled Measurements and Prototype
  Theory

abstract:
  We analyze the meaning of the violation of the marginal probability law for
situations of correlation measurements where entanglement is identified. We
show that for quantum theory applied to the cognitive realm such a violation
does not lead to the type of problems commonly believed to occur in situations
of quantum theory applied to the physical realm. We briefly situate our quantum
approach for modeling concepts and their combinations with respect to the
notions of 'extension' and 'intension' in theories of meaning, and in existing
concept theories.


title:
A Study of Highly Frustrated Spin Systems with mixed PEPS in Infinite
  Honeycomb Lattice

abstract:
  Highly frustrated spin systems represent a central and challenging problem in
condensed mater physics. To this problem, we introduce an algorithm based on
mixed projected entangled pair states (m-PEPS), which is a novel type of tensor
network. We use the famous Kitaev model on an infinite honeycomb lattice, which
can be solved exactly, as a benchmark. With very limited parameters and finite
scaling, our calculation results are in good agreement with the exact results,
indicating the efficiency of our algorithm. After presenting the benchmark, we
investigate the Kitaev-Heisenberg model, which was proposed to describe the
effective magnetic momentum interaction in iridate Na$_2$IrO$_3$ which may be
used to realize the spin liquid phase. However, our calculations suggest that
the gapless spin liquid phase is not robust at the thermodynamic limit, and
thus this phenomenon is very difficult to observe.


title: The SDSS Galaxy Angular Two-Point Correlation Function

abstract:
  We present the galaxy two-point angular correlation function for galaxies
selected from the seventh data release of the Sloan Digital Sky Survey. The
galaxy sample was selected with $r$-band apparent magnitudes between 17 and 21;
and we measure the correlation function for the full sample as well as for the
four magnitude ranges: 17-18, 18-19, 19-20, and 20-21. We update the flag
criteria to select a clean galaxy catalog and detail specific tests that we
perform to characterize systematic effects, including the effects of seeing,
Galactic extinction, and the overall survey uniformity. Notably, we find that
optimally we can use observed regions with seeing $< 1\farcs5$, and $r$-band
extinction < 0.13 magnitudes, smaller than previously published results.
Furthermore, we confirm that the uniformity of the SDSS photometry is minimally
affected by the stripe geometry. We find that, overall, the two-point angular
correlation function can be described by a power law, $\omega(\theta) =
A_\omega \theta^{(1-\gamma)}$ with $\gamma \simeq 1.72$, over the range
$0\fdg005$--$10\degr$. We also find similar relationships for the four
magnitude subsamples, but the amplitude within the same angular interval for
the four subsamples is found to decrease with fainter magnitudes, in agreement
with previous results. We find that the systematic signals are well below the
galaxy angular correlation function for angles less than approximately
$5\degr$, which limits the modeling of galaxy angular correlations on larger
scales. Finally, we present our custom, highly parallelized two-point
correlation code that we used in this analysis.


title: Device-independent demonstration of genuine multipartite entanglement

abstract:
  Entanglement in a quantum system can be demonstrated experimentally by
performing the measurements prescribed by an appropriate entanglement witness.
However, the unavoidable mismatch between the implementation of measurements in
practical devices and their precise theoretical modelling generally results in
the undesired possibility of false-positive entanglement detection. Such
scenarios can be avoided by using the recently developed device-independent
entanglement witnesses (DIEWs) for genuine multipartite entanglement. Similarly
to Bell inequalities, DIEWs only assume that consistent measurements are
performed locally on each subsystem. No precise description of the measurement
devices is required. Here we report an experimental test of DIEWs on up to six
entangled 40Ca+ ions. We also demonstrate genuine multipartite quantum
nonlocality between up to six parties with the detection loophole closed.


title: Nilpotence and the generalized uncertainty principle(s)

abstract:
  We point out that some of the proposed generalized/modified uncertainty
principles originate from solvable, or nilpotent at appropriate limits,
"deformations" of Lie algebras. We briefly comment on formal aspects related to
the well-posedness of one of these algebras. We point out a potential relation
of such algebras with Classical Mechanics in the spirit of the symplectic
non-squeezing theorem. We also point out their relation to a hierarchy of
generalized measure theories emerging in a covariant formalism of quantum
gravity.


title: Set Theory and p-adic Algebras

abstract:
  We verified that the existence of a maximal ideal of height 0 in a p-adic
algebra in a certain class is independent of the axiom of ZFC. We established
the theory on a P-point in the boundary of a topological space in the universal
totally disconnected Hausdorff compactification. It is quite similar with the
theory on a P-point in the boundary of a topological space in the Stone-Cech
compactification. The latter theory relies on the real analysis, and the reason
why the real analysis works for it is because the Stone-Cech compactification
has the lifting property for a real bounded continuous function. On the other
hand, the universal totally disconnected Hausdorff compactification does not
have the lifting property for a real bounded continuous function in general,
and hence the same technique with the real analysis is not valid for the former
theory. We applied the p-adic analysis instead, and it yields a relation with a
P-point in the boundary in the universal totally disconnected Hausdorff
compactification and a maximal ideal of height 0 in the corresponding p-adic
algebra.


title:
Electromagnetic Duality and New Solutions of the Non-minimally Coupled
  Y(R)-Maxwell Gravity

abstract:
  Non-minimally coupled Y(R)-Maxwell gravity which have some interesting
solutions may be used to understand dark matter, dark energy, the origin of
cosmic magnetic field and the evaluation of the universe. We give some new
solutions to the model such as spherically symmetric electric, magnetic and
dyon solutions. We point out an existence of an electromagnetic duality
transformation for the model.


title:
Least-Squares FIR Models of Low-Resolution MR data for Efficient
  Phase-Error Compensation with Simultaneous Artefact Removal

abstract:
  Signal space models in both phase-encode, and frequency-encode directions are
presented for extrapolation of 2D partial kspace. Using the boxcar
representation of low-resolution spatial data, and a geometrical representation
of signal space vectors in both positive and negative phase-encode directions,
a robust predictor is constructed using a series of signal space projections.
Compared to some of the existing phase-correction methods that require
acquisition of a pre-determined set of fractional kspace lines, the proposed
predictor is found to be more efficient, due to its capability of exhibiting an
equivalent degree of performance using only half the number of fractional
lines. Robust filtering of noisy data is achieved using a second signal space
model in the frequency-encode direction, bypassing the requirement of a prior
highpass filtering operation. The signal space is constructed from Fourier
Transformed samples of each row in the low-resolution image. A set of FIR
filters are estimated by fitting a least squares model to this signal space.
Partial kspace extrapolation using the FIR filters is shown to result in
artifact-free reconstruction, particularly in respect of Gibbs ringing and
streaking type artifacts.


title: A Taxonomy of Hyperlink Hiding Techniques

abstract:
  Hidden links are designed solely for search engines rather than visitors. To
get high search engine rankings, link hiding techniques are usually used for
the profitability of black industries, such as illicit game servers, false
medical services, illegal gambling, and less attractive high-profit industry,
etc. This paper investigates hyperlink hiding techniques on the Web, and gives
a detailed taxonomy. We believe the taxonomy can help develop appropriate
countermeasures. Study on 5,583,451 Chinese sites' home pages indicate that
link hidden techniques are very prevalent on the Web. We also tried to explore
the attitude of Google towards link hiding spam by analyzing the PageRank
values of relative links. The results show that more should be done to punish
the hidden link spam.


title:
Voxel-wise Weighted MR Image Enhancement using an Extended Neighborhood
  Filter

abstract:
  We present an edge preserving and denoising filter for enhancing the features
in images, which contain an ROI having a narrow spatial extent. Typical
examples include angiograms, or ROI spatially distributed in multiple locations
and contained within an outlying region, such as in multiple-sclerosis. The
filtering involves determination of multiplicative weights in the spatial
domain using an extended set of neighborhood directions. Equivalently, the
filtering operation may be interpreted as a combination of directional filters
in the frequency domain, with selective weighting for spatial frequencies
contained within each direction. The advantages of the proposed filter in
comparison to specialized non-linear filters, which operate on diffusion
principle, are illustrated using numerical phantom data. The performance
evaluation is carried out on simulated images from BrainWeb database for
multiple-sclerosis, acute ischemic stroke using clinically acquired FLAIR
images and MR angiograms.


title: Heavy dilepton in nucleus nucleus collision at LHC energy

abstract:
  We present a study of $\tau^+ \tau^-$ lepton pair production in Pb + Pb
collisions at $\sqrt{s_{NN}}$ = 5.5 TeV. The larger mass of tau lepton compared
to electron and muon leads to considerably small hadronic contribution to the
$\tau^+ \tau^-$ pair invariant mass (M) distribution relative to the production
from thermal partonic sources. The quark-antiquark annihilation processes via
intermediary virtual photon, Z and Higgs bosons have been considered for the
tau lepton production. The contribution from Drell-Yan process is found to
dominate over thermal yield for $\tau^+ \tau^-$ pair mass from 4 to 20 GeV at
the LHC energy. We also present the ratio of $\tau$ lepton pair yields for
nucleus-nucleus collisions relative to yields from p + p collisions scaled by
number of binary collisions at LHC energies as a function $\tau$ lepton pair
inavariant mass. The ratio is found to be significantly above unity for the
mass range 4 to 6 GeV. This indicates the possibility of detecting $\tau^+
\tau^-$ pair from quark gluon plasma (QGP) in the mass window 4 to 6 GeV.


title:
On the cyclicity of the period annulus of quadratic Hamiltonian triangle
  vector field

abstract:
  This paper is concerned with the cyclicity of the period annulus of quadratic
Hamiltonian triangle vector field under quadratic perturbations. This problem
has been studied by Iliev (J. Differential Equations {\bf 128}(1996)), based on
the displacement function obtained by \.{Z}o{\l}adek (J. Differential Equations
{\bf 109}(1994)). Recently, P. Marde\v{s}i\'{c} etc. (J. Dynamical and Control
Systems {\bf 17}(2011)) studied unfoldings of the Hamiltonian triangle within
quadratic vector fields. It turned out that the displacement function is not
precise of the form given by \.{Z}o{\l}adek. Using the corrected form of the
displacement function obtained by P. Marde\v{s}i\'{c} etc, it is proved in this
paper that the cyclicity of the period annulus under quadratic perturbations is
equal to three.


title:
The Shoenberg Effect in Relativistic Degenerate Electron Gas and
  Observational Evidences in Magnetars

abstract:
  The electron gas inside a neutron star is highly degenerate and relativistic.
Due to the electron-electron magnetic interaction, the differential
susceptibility can equal or exceed 1, which causes the magnetic system of the
neutron star to become metastable or unstable. The Fermi liquid of nucleons
under the crust can be in a metastable state, while the crust is unstable to
the formation of layers of alternating magnetization. The change of the
magnetic stress acting on adjacent domains can result in a series of shifts or
fractures in the crust. The releasing of magnetic free energy and elastic
energy in the crust can cause the bursts observed in magnetars. Simultaneously,
a series of shifts or fractures in the deep crust which is closed to the Fermi
liquid of nucleons can trigger the phase transition of the Fermi liquid of
nucleons from a metastable state to a stable state. The released magnetic free
energy in the Fermi liquid of nucleons corresponds to the giant flares observed
in some magnetars.


title:
Uniqueness and Lipschitz stability for the identification of Lam\'e
  parameters from boundary measurements

abstract:
  In this paper we consider the problem of determining an unknown pair
$\lambda$, $\mu$ of piecewise constant Lam\'{e} parameters inside a three
dimensional body from the Dirichlet to Neumann map. We prove uniqueness and
Lipschitz continuous dependence of $\lambda$ and $\mu$ from the Dirichlet to
Neumann map.


title: Rossby waves trapped by quantum mechanics

abstract:
  Extended abstract for the workshop "Geophysical Fluid Dynamics " held in
Oberwolfach, 17 February - 23 February 2013, to be published by the
Mathematisches Forschungsinstitut Oberwolfach in the "Oberwolfach Reports"
series.


title: Numerical Simulations of Kinetic Models for chemotaxis

abstract:
  We present a new algorithm based on a Cartesian mesh for the numerical
approximation of kinetic models for chemosensitive movements set in an
arbitrary geometry. We investigate the influence of the geometry on the
collective behavior of bacteria described by a kinetic equation interacting
with nutrients and chemoattractants. Numerical simulations are performed to
verify accuracy and stability of the scheme and its ability to exhibit
aggregation of cells and wave propagations. Finally some comparisons with
experiments show the robustness and accuracy of such kinetic models.


title: Broadening the Scope of Nanopublications

abstract:
  In this paper, we present an approach for extending the existing concept of
nanopublications --- tiny entities of scientific results in RDF representation
--- to broaden their application range. The proposed extension uses English
sentences to represent informal and underspecified scientific claims. These
sentences follow a syntactic and semantic scheme that we call AIDA (Atomic,
Independent, Declarative, Absolute), which provides a uniform and succinct
representation of scientific assertions. Such AIDA nanopublications are
compatible with the existing nanopublication concept and enjoy most of its
advantages such as information sharing, interlinking of scientific findings,
and detailed attribution, while being more flexible and applicable to a much
wider range of scientific results. We show that users are able to create AIDA
sentences for given scientific results quickly and at high quality, and that it
is feasible to automatically extract and interlink AIDA nanopublications from
existing unstructured data sources. To demonstrate our approach, a web-based
interface is introduced, which also exemplifies the use of nanopublications for
non-scientific content, including meta-nanopublications that describe other
nanopublications.


title:
Context-aware Sensor Search, Selection and Ranking Model for Internet of
  Things Middleware

abstract:
  As we are moving towards the Internet of Things (IoT), the number of sensors
deployed around the world is growing at a rapid pace. Market research has shown
a significant growth of sensor deployments over the past decade and has
predicted a substantial acceleration of the growth rate in the future. It is
also evident that the increasing number of IoT middleware solutions are
developed in both research and commercial environments. However, sensor search
and selection remain a critical requirement and a challenge. In this paper, we
present CASSARAM, a context-aware sensor search, selection, and ranking model
for Internet of Things to address the research challenges of selecting sensors
when large numbers of sensors with overlapping and sometimes redundant
functionality are available. CASSARAM proposes the search and selection of
sensors based on user priorities. CASSARAM considers a broad range of
characteristics of sensors for search such as reliability, accuracy, battery
life just to name a few. Our approach utilises both semantic querying and
quantitative reasoning techniques. User priority based weighted Euclidean
distance comparison in multidimensional space technique is used to index and
rank sensors. Our objectives are to highlight the importance of sensor search
in IoT paradigm, identify important characteristics of both sensors and data
acquisition processes which help to select sensors, understand how semantic and
statistical reasoning can be combined together to address this problem in an
efficient manner. We developed a tool called CASSARA to evaluate the proposed
model in terms of resource consumption and response time.


title:
Automatic Detection of Non-deverbal Event Nouns for Quick Lexicon
  Production

abstract:
  In this work we present the results of our experimental work on the
develop-ment of lexical class-based lexica by automatic means. The objective is
to as-sess the use of linguistic lexical-class based information as a feature
selection methodology for the use of classifiers in quick lexical development.
The results show that the approach can help in re-ducing the human effort
required in the development of language resources sig-nificantly.


title:
Using qualia information to identify lexical semantic classes in an
  unsupervised clustering task

abstract:
  Acquiring lexical information is a complex problem, typically approached by
relying on a number of contexts to contribute information for classification.
One of the first issues to address in this domain is the determination of such
contexts. The work presented here proposes the use of automatically obtained
FORMAL role descriptors as features used to draw nouns from the same lexical
semantic class together in an unsupervised clustering task. We have dealt with
three lexical semantic classes (HUMAN, LOCATION and EVENT) in English. The
results obtained show that it is possible to discriminate between elements from
different lexical semantic classes using only FORMAL role information, hence
validating our initial hypothesis. Also, iterating our method accurately
accounts for fine-grained distinctions within lexical classes, namely
distinctions involving ambiguous expressions. Moreover, a filtering and
bootstrapping strategy employed in extracting FORMAL role descriptors proved to
minimize effects of sparse data and noise in our task.


title:
Strong-coupling analysis of scanning tunneling spectra in
  Bi$_2$Sr$_2$Ca$_2$Cu$_3$O$_{10+\delta}$

abstract:
  We study a series of spectra measured in the superconducting state of
optimally-doped Bi-2223 by scanning tunneling spectroscopy. Each spectrum, as
well as the average of spectra presenting the same gap, is fitted using a
strong-coupling model taking into account the band structure, the BCS gap, and
the interaction of electrons with the spin resonance. After describing our
measurements and the main characteristics of the strong-coupling model, we
report the whole set of parameters determined from the fits, and we discuss
trends as a function of the gap magnitude. We also simulate angle-resolved
photoemission spectra, and compare with recent experimental results.


title:
The best bounds for Toader mean in terms of the centroidal and
  arithmetic means

abstract:
  In the paper, the authors discover the best constants $\alpha_{1}$,
$\alpha_{2}$, $\beta_{1}$, and $\beta_{2}$ for the double inequalities $$
\alpha_{1}\bar{C}(a,b)+(1-\alpha_{1}) A(a,b)< T(a,b) <\beta_{1}
\bar{C}(a,b)+(1-\beta_{1})A(a,b) $$ and $$
\frac{\alpha_{2}}{A(a,b)}+\frac{1-\alpha_{2}}{\bar{C}(a,b)}<\frac1{T(a,b)}
<\frac{\beta_{2}}{A(a,b)}+\frac{1-\beta_{2}}{\bar{C}(a,b)} $$ to be valid for
all $a,b>0$ with $a\ne b$, where $$
\bar{C}(a,b)=\frac{2(a^{2}+ab+b^{2})}{3(a+b)},\quad A(a,b)=\frac{a+b}2, $$ and
$$
T(a,b)=\frac{2}{\pi}\int_{0}^{{\pi}/{2}}\sqrt{a^2{\cos^2{\theta}}+b^2{\sin^2{\theta}}}\,\td\theta
$$ are respectively the centroidal, arithmetic, and Toader means of two
positive numbers $a$ and $b$. As an application of the above inequalities, the
authors also find some new bounds for the complete elliptic integral of the
second kind.


title: Max-stable processes and the functional D-norm revisited

abstract:
  Aulbach et al. (2013) introduced a max-domain of attraction approach for
extreme value theory in C[0,1] based on functional distribution functions,
which is more general than the approach based on weak convergence in de Haan
and Lin (2001). We characterize this new approach by decomposing a process into
its univariate margins and its copula process. In particular, those processes
with a polynomial rate of convergence towards a max-stable process are
considered. Furthermore we investigate the concept of differentiability in
distribution of a max-stable processes.


title: Collapsible Pushdown Graphs of Level 2 are Tree-Automatic

abstract:
  We show that graphs generated by collapsible pushdown systems of level 2 are
tree-automatic. Even if we allow epsilon-contractions and reachability
predicates (with regular constraints) for pairs of configurations, the
structures remain tree-automatic whence their first-order logic theories are
decidable. As a corollary we obtain the tree-automaticity of the second level
of the Caucal-hierarchy.


title: Donors of Persistent Neutron-star Low-mass X-ray Binaries

abstract:
  Properties of X-ray luminosities in low-mass X-ray binaries (LMXBs) mainly
depend on donors. We have carried out a detailed study of donors in persistent
neutron-star LMXBs (PLMXBs) by means of a population synthesis code. PLMXBs
with different donors have different formation channels. Our numerical
simulations show that more than 90% of PLMXBs have main sequence (MS) donors,
and PLMXBs with red giant (RG) donors via stellar wind (Wind) are negligible.
In our model, most of neutron stars (NSs) in PLMXBs with hydrogen-rich donors
form via core-collapse supernovae, while more than 90% of NSs in PLMXBs with
naked helium star (He) donors or white dwarf (WD) donors form via an
evolution-induced collapse via helium star ($1.4 \leq M_{\rm He}/M_\odot \leq
2.5$) or an accretion-induced collapses for an accreting ONeMg WD.


title:
Shock problem for MKdV equation: Long time Dynamics of the Step-like
  initial data

abstract:
  We consider the modified Korteveg de Vriez equation on the whole line.
Initial data is real and step-like, i.e. $q(x,0)=0$ for $x\geq0$ and $q(x,0)=c$
for $x<0$, where c is arbitrary real number. The goal of this paper is to study
the asymptotic behavior of the initial-value problem's solution by means of the
asymptotic behavior of the some Riemann\textendash Hilbert problem. In this
paper we show that the solution of this problem has different asymptotic
behavior in different regions. In the region $x<-6c^2t$ and $x>4c^2t$ the
solution is tend to $c$ and 0 correspondingly. In the region $-6c^2t<x<4c^2t$
the solution takes the form of a modulated elliptic wave.


title:
High-frequency asymptotics for Lipschitz-Killing curvatures of excursion
  sets on the sphere

abstract:
  In this paper, we shall be concerned with geometric functionals and excursion
probabilities for some nonlinear transforms evaluated on Fourier components of
spherical random fields. In particular, we consider both random spherical
harmonics and their smoothed averages, which can be viewed as random wavelet
coefficients in the continuous case. For such fields, we consider smoothed
polynomial transforms; we focus on the geometry of their excursion sets, and we
study their asymptotic behaviour, in the high-frequency sense. We focus on the
analysis of Euler-Poincar\'{e} characteristics, which can be exploited to
derive extremely accurate estimates for excursion probabilities. The present
analysis is motivated by the investigation of asymmetries and anisotropies in
cosmological data. The statistics we focus on are also suitable to deal with
spherical random fields which can only be partially observed, the canonical
example being provided by the masking effect of the Milky Way on Cosmic
Microwave Background (CMB) radiation data.


title: Real and complex rank for real symmetric tensors with low ranks

abstract:
  We study the case of a real homogeneous polynomial $P$ whose minimal real and
complex decompositions in terms of powers of linear forms are different. We
prove that, if the sum of the complex and the real ranks of $P$ is at most $
3\deg(P)-1$, then the difference of the two decompositions is completely
determined either on a line or on a conic or two disjoint lines.


title: Low-mass X-ray Binaries with Strange Quark Stars

abstract:
  Strange quark stars (SSs) may originate from accreting neutron stars (NSs) in
low-mass X-ray binaries (LMXBs). Assuming that conversion of NS matter to SSs
occurs when the core density of accreting NS reaches to the density of quark
deconfinement, $\sim 5 \rho_0$, where $\rho_0\sim 2.7\times 10^{14}$g cm$^{-3}$
is nuclear saturation density, we investigate LMXBs with SSs (qLMXBs). In our
simulations, about 1\permil --- 10% of LMXBs can produce SSs, which greatly
depends on the masses of nascent NSs and the fraction of transferred matter
accreted by the NSs. If the conversion does not affect binaries systems, LMXBs
evolve into qLMXBs. We find that some observational properties (spin periods,
X-ray luminosities and orbital periods) of qLMXBs are similar with those of
LMXBs, and it is difficult to differ them. If the conversion disturbs the
binaries systems, LMXBs can produce isolated SSs. These isolated SSs could be
submillisecond pulsars, and their birthrate in the Galaxy is $\sim$5--70 per
Myr.


title:
A probabilistic proof of the fundamental gap conjecture via the coupling
  by reflection

abstract:
  Let $\Omega\subset\mathbb{R}^n$ be a strictly convex domain with smooth
boundary and diameter $D$. The fundamental gap conjecture claims that if
$V:\bar\Omega\to\mathbb{R}$ is convex, then the spectral gap of the
Schr\"odinger operator $-\Delta+V$ with Dirichlet boundary condition is greater
than $\frac{3\pi^2}{D^2}$. Using analytic methods, Andrews and Clutterbuck
recently proved in [J. Amer. Math. Soc. 24 (2011), no. 3, 899--916] a more
general spectral gap comparison theorem which implies this conjecture. In the
first part of the current work, we shall give an independent probabilistic
proof of their result via the coupling by reflection of the diffusion
processes. Moreover, we also present in the second part a simpler probabilistic
proof of the original conjecture.


title: Thermally activated recovery of electrical conductivity in LaAlO3/SrTiO3

abstract:
  Patterned structures of LaAlO3/SrTiO3 that exhibit a decrease in their
electrical conductivity below 30 K, recover their higher conductivity upon
warming in a thermally activated process. Two dominant energy barriers $E_b$
are identified: $E_{b1}=0.224\pm0.003$ eV related to conductivity recovery near
70 K and $E_{b2}=0.44\pm0.015$ eV related to conductivity recovery near 160 K.
We discuss possible linkage to structural defects such as dislocations and twin
boundaries.


title: Spin and transverse momentum dependent Fracture Function in SIDIS

abstract:
  The recently developed leading twist formalism for spin and
transverse-momentum dependent fracture functions is shortly described. We
demonstrate that the process of double hadron production in polarized SIDIS --
with one spinless hadron produced in the current fragmentation region (CFR) and
another in the target fragmentation region (TFR) -- would provide access to all
16 leading twist fracture functions. Some particular cases are presented.


title: Characterizations of periods of multidimensional shifts

abstract:
  We show that the sets of periods of multidimensional shifts of finite type
(SFTs) are exactly the sets of integers of the complexity class $\NE$. We also
show that the functions counting their number are the functions of #E. We also
give characterizations of some other notions of periodicity. We finish the
paper by giving some characterizations for sofic and effective subshifts.


title: The Shape of Dark Matter Haloes, I. HI Observations of Edge-on Galaxies

abstract:
  We present neutral hydrogen observations for a sample of eight nearby,
late-type, edge-on galaxies. All of the galaxies have been well resolved in the
radial direction, while six have also been well resolved in the vertical
direction. We find that each of the galaxies has approximately the same maximum
surface brightness temperature throughout its disc. We argue that
self-absorption is the main cause of this phenomenon and that subsequent
decompositions will require a treatment of this.


title:
Physical properties of outflows: Comparing CO and H2O based parameters
  in Class 0 sources

abstract:
  Context. The observed physical properties of outflows from low-mass sources
put constraints on possible ejection mechanisms. Historically, these quantities
have been derived from CO using ground-based observations. It is thus important
to investigate whether parameters such as momentum rate (thrust) and mechanical
luminosity (power) are the same when different molecular tracers are used.
Aims. We aim at determining the outflow momentum, dynamical time-scale, thrust,
energy and power using CO and H2O as tracers of outflow activity. Methods.
Within the framework of the WISH key program, three molecular outflows from
Class 0 sources have been mapped using the HIFI instrument aboard Herschel. We
use these observations together with previously published H2 data to infer the
physical properties of the outflows. We compare the physical properties derived
here with previous estimates based on CO observations. Results. Inspection of
the spatial distribution of H2O and H2 confirms that these molecules are
co-spatial. The most prominent emission peaks in H2 coincide with strong H2O
emission peaks and the estimated widths of the flows when using the two tracers
are comparable. Conclusions. For the momentum rate and the mechanical
luminosity, inferred values are independent of which tracer that is used, i.e.,
the values agree to within a factor of 4 and 3 respectively.


title:
A Low-Complexity Algorithm for Static Background Estimation from
  Cluttered Image Sequences in Surveillance Contexts

abstract:
  For the purposes of foreground estimation, the true background model is
unavailable in many practical circumstances and needs to be estimated from
cluttered image sequences. We propose a sequential technique for static
background estimation in such conditions, with low computational and memory
requirements. Image sequences are analysed on a block-by-block basis. For each
block location a representative set is maintained which contains distinct
blocks obtained along its temporal line. The background estimation is carried
out in a Markov Random Field framework, where the optimal labelling solution is
computed using iterated conditional modes. The clique potentials are computed
based on the combined frequency response of the candidate block and its
neighbourhood. It is assumed that the most appropriate block results in the
smoothest response, indirectly enforcing the spatial continuity of structures
within a scene. Experiments on real-life surveillance videos demonstrate that
the proposed method obtains considerably better background estimates (both
qualitatively and quantitatively) than median filtering and the recently
proposed "intervals of stable intensity" method. Further experiments on the
Wallflower dataset suggest that the combination of the proposed method with a
foreground segmentation algorithm results in improved foreground segmentation.


title: Spherical roots of spherical varieties

abstract:
  Brion proved that the valuation cone of a complex spherical variety is a
fundamental domain for a finite reflection group, called the little Weyl group.
The principal goal of this paper is to generalize this fundamental theorem to
fields of characteristic unequal to 2. We also prove a weaker version which
holds in characteristic 2, as well. Our main tool is a generalization of
Akhiezer's classification of spherical rank-1-varieties.


title: Simulations and Bisimulations For Coalgebraic Modal Logics

abstract:
  We define a notion of Lambda-simulation for coalgebraic modal logics,
parametric on the choice Lambda of predicate liftings for a functor T. We show
this notion is adequate in several ways: i) it preserves truth of positive
formulas, ii) for Lambda a separating set of monotone predicate liftings, the
associated notion of Lambda-bisimulation corresponds to T-behavioural
equivalence (moreover Lambda-n-bisimulations correspond to T-n-behavioural
equivalence), and iii) in fact, for Lambda-separating and T preserving weak
pullbacks, difunctional Lambda-bisimulations are T-bisimulations. In essence,
we arrive at a modular notion of equivalence that, when used with a separating
set of monotone predicate liftings, coincides with T-behavioural equivalence
regardless of whether T preserves weak pullbacks (unlike the notion of
T-bisimilarity).


title:
Integrability conditions for space-time stochastic integrals: Theory and
  applications

abstract:
  We derive explicit integrability conditions for stochastic integrals taken
over time and space driven by a random measure. Our main tool is a canonical
decomposition of a random measure which extends the results from the purely
temporal case. We show that the characteristics of this decomposition can be
chosen as predictable strict random measures, and we compute the
characteristics of the stochastic integral process. We apply our conditions to
a variety of examples, in particular to ambit processes, which represent a rich
model class.


title:
Quintessence with Kaluza-Klein type couplings to matter and an
  isotropy-violating vector field

abstract:
  We study the dynamics of a scalar field with Kaluza-Klein type couplings to
cold dark matter and an isotropy-violating vector field. The vector coupling,
$f^2(\phi)F^2$, has been studied thoroughly in the context of inflation
recently. We generalize the model to a dark energy context and study the
cosmological consequences. We find a rich set of exact anisotropic power-law
solutions and identify a strong vector coupling regime where the anisotropy is
controllable and all solutions are close to the LCDM limit.


title:
Accounting for adsorption and desorption in lattice Boltzmann
  simulations

abstract:
  We report a Lattice-Boltzmann scheme that accounts for adsorption and
desorption in the calculation of mesoscale dynamical properties of tracers in
media of arbitrary complexity. Lattice Boltzmann simulations made it possible
to solve numerically the coupled Navier-Stokes equations of fluid dynamics and
Nernst-Planck equations of electrokinetics in complex, heterogeneous media.
Associated to the moment propagation scheme, it became possible to extract the
effective diffusion and dispersion coefficients of tracers, or solutes, of any
charge, e.g. in porous media. Nevertheless, the dynamical properties of tracers
depend on the tracer-surface affinity, which is not purely electrostatic, but
also includes a species-specific contribution. In order to capture this
important feature, we introduce specific adsorption and desorption processes in
a Lattice-Boltzmann scheme through a modified moment propagation algorithm, in
which tracers may adsorb and desorb from surfaces through kinetic reaction
rates. The method is validated on exact results for pure diffusion and
diffusion-advection in Poiseuille flows in a simple geometry. We finally
illustrate the importance of taking such processes into account on the
time-dependent diffusion coefficient in a more complex porous medium.


title: Fully coherent follow-up of continuous gravitational-wave candidates

abstract:
  The search for continuous gravitational waves from unknown isolated sources
is computationally limited due to the enormous parameter space that needs to be
covered and the weakness of the expected signals. Therefore semi-coherent
search strategies have been developed and applied in distributed computing
environments such as Einstein@Home, in order to narrow down the parameter space
and identify interesting candidates. However, in order to optimally confirm or
dismiss a candidate as a possible gravitational-wave signal, a fully-coherent
follow-up using all the available data is required.
  We present a general method and implementation of a direct (2-stage)
transition to a fully-coherent follow-up on semi-coherent candidates. This
method is based on a grid-less Mesh Adaptive Direct Search (MADS) algorithm
using the F-statistic. We demonstrate the detection power and computing cost of
this follow-up procedure using extensive Monte-Carlo simulations on (simulated)
semi-coherent candidates from a directed as well as from an all-sky search
setup.


title:
New topological surface state in layered topological insulators:
  unoccupied Dirac cone

abstract:
  The unoccupied states in topological insulators Bi_2Se_3, PbSb_2Te_4, and
Pb_2Bi_2Te_2S_3 are studied by the density functional theory methods. It is
shown that a surface state with linear dispersion emerges in the inverted
conduction band energy gap at the center of the surface Brillouin zone on the
(0001) surface of these insulators. The alternative expression of Z_2 invariant
allowed us to show that a necessary condition for the existence of the second
Gamma Dirac cone is the presence of local gaps at the time reversal invariant
momentum points of the bulk spectrum and change of parity in one of these
points.


title:
On the role of initial and boundary conditions in numerical simulations
  of accretion flows

abstract:
  We study the effects of initial and boundary conditions, taking
two-dimensional hydrodynamical numerical simulations of hot accretion flow as
an example. The initial conditions considered include a rotating torus, a
solution expanded from the one-dimensional global solution of hot accretion
flows, injected gas with various angular momentum distributions, and the gas
from a large-scale numerical simulation. Special attention is paid to the
radial profiles of the mass accretion rate and density. Both can be described
by a power-law function, $\dot{M}\propto r^s$ and $\rho\propto r^{-p}$. We find
that if the angular momentum is not very low, the value of $s$ is not sensitive
to the initial condition and lies within a narrow range, $0.47\la s \la 0.55$.
However, the value of $p$ is more sensitive to the initial condition and lies
in the range $0.48\la p \la 0.8$. The diversity of the density profile is
because different initial conditions give different radial profiles of radial
velocity due to the different angular momentum of the initial conditions. When
the angular momentum of the accretion flow is very low, the inflow rate is
constant with radius. Taking the torus model as an example, we have also
investigated the effects of inner and outer boundary conditions by considering
the widely adopted "outflow" boundary condition and the "mass flux
conservation" condition. We find that the results are not sensitive to these
two boundary conditions.


title: A two-dimensional quantum gas in a magnetic trap

abstract:
  We present the first experimental realization of a two-dimensional quantum
gas in a purely magnetic trap dressed by a radio frequency field in the
presence of gravity. The resulting potential is extremely smooth and very close
to harmonic in the two-dimensional plane of confinement. We fully characterize
the trap and demonstrate the confinement of a quantum gas to two dimensions.
The trap geometry can be modified to a large extent, in particular in a
dynamical way. Taking advantage of this possibility, we study the monopole and
the quadrupole modes of a two-dimensional Bose gas.


title: Centre of the Schur Algebra

abstract:
  We describe a basis of the centre of the Schur algebra which comes from
conjugacy classes in the symmetric group via Schur-Weyl duality. We give a
combinatorial description of expansions of these basis elements in terms of the
basis originally used by Schur. The primitive central idempotents of the Schur
algebra can be written down using this basis and the character table of the
symmetric group. Along the way we prove a result on the non-singularity of the
submatrix of the character table matrix of a symmetric group obtained by taking
rows and columns indexed by partitions with at most n parts for any n.


title: Heavy flavor suppression: role of hadronic matter

abstract:
  The role of hadronic matter in the suppression of open heavy flavored mesons
has been studied. The heavy-quarks (HQs) suppression factors have been
calculated and contrasted with the experimental data obtained from nuclear
collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadronic
Collider (LHC) experiments. It is found that the suppression in the hadronic
phase at RHIC energy is around $20%-25%$ whereas at the LHC it is around
$10%-12%$ for the D meson. In case of B meson the hadronic suppression is
around $10%-12%$ and $5%-6%$ at RHIC and LHC energies respectively. Present
study suggests that the suppression of heavy flavor in the hadronic phase is
significant at RHIC. However, the effect of hadronic suppression at LHC is
marginal, this makes the characterization of QGP at LHC less complicated.


title: A coupling pair of dwarfs in Lynx

abstract:
  We report on discovery of unique binary system of dIr galaxies which looks
like a low surface brightness tidal stream in the halo of another dwarf galaxy.
Both the galaxies are detected in the HI line with the Giant Metrewave Radio
Telescope (GMRT). The pair components have absolute blue magnitudes -16.0 and
-13.2, heliocentric radial velocities 1799 and 1842 km/s, and hydrogen
masses-to-luminosity ratios 0.4 and 1.6 in solar units, respectively. The
binary system is characterized by a high orbital mass-to-luminosity ratio of 49
in solar units and a short crossing time of 0.22 Gyr.


title: The Price of Connectivity for Vertex Cover

abstract:
  The vertex cover number of a graph is the minimum number of vertices that are
needed to cover all edges. When those vertices are further required to induce a
connected subgraph, the corresponding number is called the connected vertex
cover number, and is always greater or equal to the vertex cover number.
  Connected vertex covers are found in many applications, and the relationship
between those two graph invariants is therefore a natural question to
investigate. For that purpose, we introduce the {\em Price of Connectivity},
defined as the ratio between the two vertex cover numbers. We prove that the
price of connectivity is at most 2 for arbitrary graphs. We further consider
graph classes in which the price of connectivity of every induced subgraph is
bounded by some real number $t$. We obtain forbidden induced subgraph
characterizations for every real value $t \leq 3/2$.
  We also investigate critical graphs for this property, namely, graphs whose
price of connectivity is strictly greater than that of any proper induced
subgraph. Those are the only graphs that can appear in a forbidden subgraph
characterization for the hereditary property of having a price of connectivity
at most $t$. In particular, we completely characterize the critical graphs that
are also chordal.
  Finally, we also consider the question of computing the price of connectivity
of a given graph. Unsurprisingly, the decision version of this question is
NP-hard. In fact, we show that it is even complete for the class $\Theta_2^P =
P^{NP[\log]}$, the class of decision problems that can be solved in polynomial
time, provided we can make $O(\log n)$ queries to an NP-oracle. This paves the
way for a thorough investigation of the complexity of problems involving ratios
of graph invariants.


title:
Orthogonality with respect to a Jacobi differential operator and
  applications

abstract:
  In this manuscript we study algebraic and analytic properties of the sequence
of monic polynomials orthogonal with respect to a Jacobi differential operator.
A fluid dynamics model for source points location of a flow of an
incompressible fluid with preassigned stagnation points is also considered.


title: Compact moduli spaces for slope-semistable sheaves

abstract:
  We resolve pathological wall-crossing phenomena for moduli spaces of sheaves
on higher-dimensional base manifolds. This is achieved by considering
slope-semistability with respect to movable curves rather than divisors.
Moreover, given a projective n-fold and a curve C that arises as the complete
intersection of n-1 very ample divisors, we construct a modular
compactification of the moduli space of vector bundles that are slope-stable
with respect to C. Our construction generalises the algebro-geometric
construction of the Donaldson-Uhlenbeck compactification by Joseph Le Potier
and Jun Li. Furthermore, we describe the geometry of the newly construced
moduli spaces by relating them to moduli spaces of simple sheaves and to
Gieseker-Maruyama moduli spaces.


title: Trigonometric sl(2) Gaudin model with boundary terms

abstract:
  We review the derivation of the Gaudin model with integrable boundaries.
Starting from the non-symmetric R-matrix of the inhomogeneous spin-1/2 XXZ
chain and generic solutions of the reflection equation and the dual reflection
equation, the corresponding Gaudin Hamiltonians with boundary terms are
calculated. An alternative derivation based on the so-called classical
reflection equation is discussed.


title: Direct and alignment-insensitive measurement of cantilever curvature

abstract:
  We analytically derive and experimentally demonstrate a method for the
simultaneous measurement of deflection for large arrays of cantilevers. The
Fresnel diffraction patterns of a cantilever independently reveals tilt,
curvature, cubic and higher order bending of the cantilever. It provides a
calibrated absolute measurement of the polynomial coefficients describing the
cantilever shape, without careful alignment and could be applied to several
cantilevers simultaneously with no added complexity. We show that the method is
easily implemented, works in both liquid mediums and in air, for a broad range
of displacements and is especially suited to the requirements for multi-marker
biosensors.


title:
Dynamical barriers for the random ferromagnetic Ising model on the
  Cayley tree : traveling-wave solution of the real space renormalization flow

abstract:
  We consider the stochastic dynamics near zero-temperature of the random
ferromagnetic Ising model on a Cayley tree of branching ratio $K$. We apply the
Boundary Real Space Renormalization procedure introduced in our previous work
(C. Monthus and T. Garel, J. Stat. Mech. P02037 (2013)) in order to derive the
renormalization rule for dynamical barriers. We obtain that the probability
distribution $P_n(B)$ of dynamical barrier for a subtree of $n$ generations
converges for large $n$ towards some traveling-wave $P_n(B) \simeq P^*(B-nv) $,
i.e. the width of the probability distribution remains finite around an
average-value that grows linearly with the number $n$ of generations. We
present numerical results for the branching ratios K=2 and K=3. We also compute
the weak-disorder expansion of the velocity $v$ for K=2.


title: Logarithmic-scale Quasimodes that do not Equidistribute

abstract:
  Given any compact hyperbolic surface $M$, and a closed geodesic on $M$, we
construct of a sequence of quasimodes on $M$ whose microlocal lifts concentrate
positive mass on the geodesic. Thus, the Quantum Unique Ergodicity (QUE)
property does not hold for these quasimodes. This is analogous to a
construction of Faure-Nonnenmacher-De Bi\`evre in the context of quantized cat
maps, and lends credence to the suggestion that large multiplicities play a
role in the known failure of QUE for certain "toy models" of quantum chaos. We
moreover conjecture a precise threshold for the order of quasimodes needed for
QUE to hold--- the result of the present paper shows that this conjecture, if
true, is sharp.


title:
Strongly irreducible operators and indecomposable representations of
  quivers on infinite-dimensional Hilbert spaces

abstract:
  We study several classes of indecomposable representations of quivers on
infinite-dimensional Hilbert spaces and their relation. Many examples are
constructed using strongly irreducible operators. Some problems in operator
theory are rephrased in terms of representations of quivers. We shall show two
kinds of constructions of quite non-trivial indecomposable Hilbert
representations of the Kronecker quiver such that their endomorphism rings are
trivial, which are called transitive. One is a perturbation of a weighted shift
operator by a rank-one operator. The other one is a modification of an
unbounded operator used by Harrison,Radjavi and Rosenthal to provide a
transitive lattice.


title:
A Nonsmooth Maximum Principle for Optimal Control Problems with State
  and Mixed Constraints-Convex Case

abstract:
  Here we derive a nonsmooth maximum principle for optimal control problems
with both state and mixed constraints. Crucial to our development is a
convexity assumption on the "velocity set". The approach consists of applying
known penalization techniques for state constraints together with recent
results for mixed constrained problems.


title:
Coloring planar graphs with three colors and no large monochromatic
  components

abstract:
  We prove the existence of a function $f :\mathbb{N} \to \mathbb{N}$ such that
the vertices of every planar graph with maximum degree $\Delta$ can be
3-colored in such a way that each monochromatic component has at most
$f(\Delta)$ vertices. This is best possible (the number of colors cannot be
reduced and the dependence on the maximum degree cannot be avoided) and answers
a question raised by Kleinberg, Motwani, Raghavan, and Venkatasubramanian in
1997. Our result extends to graphs of bounded genus.


title: Visualizing and Interacting with Concept Hierarchies

abstract:
  Concept Hierarchies and Formal Concept Analysis are theoretically well
grounded and largely experimented methods. They rely on line diagrams called
Galois lattices for visualizing and analysing object-attribute sets. Galois
lattices are visually seducing and conceptually rich for experts. However they
present important drawbacks due to their concept oriented overall structure:
analysing what they show is difficult for non experts, navigation is
cumbersome, interaction is poor, and scalability is a deep bottleneck for
visual interpretation even for experts. In this paper we introduce semantic
probes as a means to overcome many of these problems and extend usability and
application possibilities of traditional FCA visualization methods. Semantic
probes are visual user centred objects which extract and organize reduced
Galois sub-hierarchies. They are simpler, clearer, and they provide a better
navigation support through a rich set of interaction possibilities. Since probe
driven sub-hierarchies are limited to users focus, scalability is under control
and interpretation is facilitated. After some successful experiments, several
applications are being developed with the remaining problem of finding a
compromise between simplicity and conceptual expressivity.


title: Separation Logic Modulo Theories

abstract:
  Logical reasoning about program data often requires dealing with heap
structures as well as scalar data types. Recent advances in Satisfiability
Modular Theory (SMT) already offer efficient procedures for dealing with
scalars, yet they lack any support for dealing with heap structures. In this
paper, we present an approach that integrates Separation Logic---a prominent
logic for reasoning about list segments on the heap---and SMT. We follow a
model-based approach that communicates aliasing among heap cells between the
SMT solver and the Separation Logic reasoning part. An experimental evaluation
using the Z3 solver indicates that our approach can effectively put to work the
advances in SMT for dealing with heap structures. This is the first decision
procedure for the combination of separation logic with SMT theories.


title:
Certified quantum non-demolition measurement of a macroscopic material
  system

abstract:
  Quantum non-demolition (QND) measurements improve sensitivity by evading
measurement back-action. The technique was first proposed to detect mechanical
oscillations in gravity wave detectors,and demonstrated in the measurement of
optical fields, leading to the development of rigorous criteria to distinguish
QND from similar non-classical measurements. Recent QND measurements of
macroscopic material systems such as atomic ensembles, and mechanical
oscillators, show some QND features, but not full QND character. Here we
demonstrate certified QND measurement of the collective spin of an atomic
ensemble. We observe quantum state preparation (QSP) and information-damage
trade-off (IDT) beyond their classical limits by seven and twelve standard
deviations, respectively. Our techniques complement recent work with
microscopic systems, and can be used for quantum metrology and memory, the
preparation and detection of non-gaussian states, and proposed quantum
simulation and information protocols. They should enable QND measurements of
dynamical quantum variables and the realization of QND-based quantum
information protocols.


title: The Sasaki-Ricci flow on Sasakian 3-spheres

abstract:
  We show that on a Sasakian 3-sphere the Sasaki-Ricci flow initiating from a
Sasakian metric of positive transverse scalar curvature converges to a gradient
Sasaki- Ricci soliton. We also show the existence and uniqueness of gradient
Sasaki-Ricci soliton on each Sasakian 3-sphere.


title:
Excited states in poly-diacetylene chains: A
  Density-matrix-renormalization-group study

abstract:
  We study theoretically poly-diacetylene chains diluted in their monomer
matrix. We employ the density-matrix renormalization group method (DMRG) on
finite chains to calculate the ground state and low-lying excitations of the
corresponding Peierls--Hubbard-Ohno Hamiltonian which is characterized by the
electron transfer amplitude t0 between nearest neighbors, by the
electron-phonon coupling constant \alpha, by the Hubbard interaction U, and by
the long-range interaction V. We treat the lattice relaxation in the adiabatic
limit, i.e., we calculate the polaronic lattice distortions for each excited
state. Using chains with up to 102 lattice sites, we can safely perform the
extrapolation to the thermodynamic limit for the ground-state energy and
conformation, the single-particle gap, and the energies of the singlet exciton,
the triplet ground state, and the optical excitation of the triplet ground
state. The corresponding gaps are known with high precision from experiment. We
determine a coherent parameter set (t0*=2.4 eV, \alpha*=3.4 eV/\AA, U*=6 eV,
V*=3 eV) from a fit of the experimental gap energies to the theoretical values
which we obtain for 81 parameter points in the four dimensional search space
(t0, \alpha, U, V). We identify dark in-gap states in the singlet and triplet
sectors as seen in experiment. Using a fairly stiff spring constant, the length
of our unit cell is about one percent larger than its experimental value.


title: Symmetry energy and nucleon-nucleon cross sections

abstract:
  The extension of the Boltzmann-Uehling-Uhlenbeck model of nucleus-nucleus
collision is presented. The isospin-dependent nucleon-nucleon cross sections
are estimated using the proper volume extracted from the equation of state of
the nuclear matter transformed into the form of the Van der Waals equation of
state. The results of such simulations demonstrate the dependence on symmetry
energy which typically varies strongly from the results obtained using only the
isospin-dependent mean-field. The evolution of the n/p multiplicity ratio with
angle and kinetic energy, in combination with the elliptic flow of neutrons and
protons, provides a suitable set of observables for determination of the
density dependence of the symmetry energy. The model thus provides an
environment for testing of equations of state, used for various applications in
nuclear physics and astrophysics.


title: On distributional point values and boundary values of analytic functions

abstract:
  We give the following version of Fatou's theorem for distributions that are
boundary values of analytic functions. We prove that if
$f\in\mathcal{D}^{\prime}(a,b) $ is the distributional limit of the analytic
function $F$ defined in a region of the form $(a,b) \times(0,R),$ if the one
sided distributional limit exists, $f(x_{0}+0) =\gamma,$ and if $f$ is
distributionally bounded at $x=x_{0}$, then the \L ojasiewicz point value
exists, $f(x_{0})=\gamma$ distributionally, and in particular $F(z)\to \gamma$
as $z\to x_{0}$ in a non-tangential fashion.


title:
On the rate of convergence for central limit theorems of sojourn times
  of Gaussian fields

abstract:
  The aim of this paper is to control the rate of convergence for central limit
theorems of sojourn times of Gaussian fields in both cases: the fixed and the
moving level. Our main tools are the Malliavin calculus and the Stein's method,
developed by Nualart, Peccati and Nourdin. We also extend some results of
Berman to the multidimensional case.


title:
X-ray magnetic circular dichroism experiments and theory of transuranium
  Laves phase compounds

abstract:
  The actinide cubic Laves compounds NpAl2, NpOs2, NpFe2, and PuFe2 have been
examined by X-ray magnetic circular dichroism (XMCD) at the actinide M4,5
absorption edges and Os L2,3 absorption edges. The XMCD experiments performed
at the M4,5 absorption edges of Np and Pu allow us to determine the
spectroscopic branching ratio, which gives information on the coupling scheme
in these materials. In all materials the intermediate coupling scheme is found
appropriate. Comparison with the SQUID data for NpOs2 and PuFe2 allows a
determination of the individual orbital and spin magnetic moments and the
magnetic dipole contribution mmd. The resulting orbital and spin magnetic
moments are in good agreement with earlier values determined by neutron
diffraction, and the values of mmd are non-negligible, and close to those
predicted for intermediate coupling. There is a comparatively large induced
moment on the Os atom in NpOs2 such that the Os contribution to the total
moment per formula unit is ~30% of the total. The spin and orbital moments at
the Os site are parallel, in contrast to the anti-parallel configuration of Os
impurities in 3d ferromagnetic transition metals. Calculations using the LDA+U
technique are reported. The ab initio computed XMCD spectra show good agreement
with experimental spectra for small values (0-1eV) of the Hubbard U parameter,
which underpins that 5f electrons in these compounds are relatively
delocalized.


title:
Unruh effect in vacua with anisotropic scaling: Applications to
  multilayer graphene

abstract:
  We extend the calculation of the Unruh effect to the universality classes of
quantum vacua obeying topologically protected invariance under anisotropic
scaling ${\bf r} \rightarrow b {\bf r}$, $t \rightarrow b^z t$. Two situations
are considered. The first one is related to the accelerated detector which
detects the electron - hole pairs. The second one is related to the system in
external electric field, when the electron - hole pairs are created due to the
Schwinger process. As distinct from the Unruh effect in relativistic systems
(where $z=1$) the calculated radiation is not thermal, but has properties of
systems in the vicinity of quantum criticality. The vacuum obeying anisotropic
scaling can be realized, in particular, in multilayer graphene with the
rhombohedral stacking. Opportunities of the experimental realization of Unruh
effect in this situation are discussed.


title: Asymptotic distribution of integers with certain prime factorizations

abstract:
  Let $p_{1}<p_2<... <p_{\nu}<...$ be the sequence of prime numbers and let $m$
be a positive integer. We give a strong asymptotic formula for the distribution
of the set of integers having prime factorizations of the form
$p_{m^{k_1}}p_{m^{k_{2}}...p_{m^{k_{n}}}$ with $k_{1}\le k_{2}\le...\le k_{n}$.
Such integers originate in various combinatorial counting problems; when $m=2$,
they arise as Matula numbers of certain rooted trees.


title: Interplay of roughness/modulation and curvature at proximity

abstract:
  We show that roughness or surface modulations change the distance dependence
of (power-law) interactions between curved objects at proximity. The modified
scaling law is then simply related to the order of the first non-vanishing
coefficient of the Taylor expansion of the distribution of separations between
the surfaces. The latter can in principle be estimated by scanning
measurements, or computed for well characterized modulations, and then used to
predict short-distance scaling behavior in disparate experiments. For example,
we predict that the radiative heat transfer between a rough sphere and a plate
approaches a constant with decreasing separation. Similar saturation is
expected for the Casimir force between dielectric or metallic surfaces with
appropriate modulations over distinct length scales.