title: Weak bimonoids in duoidal categories

abstract:
  Weak bimonoids in duoidal categories are introduced. They provide a common
generalization of bimonoids in duoidal categories and of weak bimonoids in
braided monoidal categories. Under the assumption that idempotent morphisms in
the base category split, they are shown to induce weak bimonads (in four
symmetric ways). As a consequence, they have four separable Frobenius base
(co)monoids, two in each of the underlying monoidal categories. Hopf modules
over weak bimonoids are defined by weakly lifting the induced comonad to the
Eilenberg-Moore category of the induced monad. Making appropriate assumptions
on the duoidal category in question, the fundamental theorem of Hopf modules is
proven which says that the category of modules over one of the base monoids is
equivalent to the category of Hopf modules if and only if a Galois-type comonad
morphism is an isomorphism.


title:
Extension of SASE bandwidth up to 2% as a way to increase the efficiency
  of protein structure determination by x-ray nanocrystallography at the
  European XFEL

abstract:
  Femtosecond x-ray nanocrystallography exploiting XFEL radiation is an
emerging method for protein structure determination using crystals with sizes
ranging from a few tens to a few hundreds nanometers. Crystals are randomly hit
by XFEL pulses, producing diffraction patterns at unknown orientations. One can
determine these orientations by studying the diffraction patterns themselves,
i.e. by indexing the Bragg peaks. The number of indexed individual images and
the SASE bandwidth are inherently linked, because increasing the number of
Bragg peaks per individual image requires increasing the bandwidth of the
spectrum. This calls for a few percent SASE bandwidth, resulting in an increase
in the number of indexed images at the same number of hits. Based on
start-to-end simulations for the baseline of the European XFEL, we demonstrate
here that it is possible to achieve up to a tenfold increase in SASE bandwidth,
compared with the nominal mode of operation. This provides a route for further
increasing the efficiency of protein structure determination at the European
XFEL. We illustrate this concept with simulations of lysozyme nanocrystals.


title:
Large-time asymptotics, vanishing viscosity and numerics for 1-D scalar
  conservation laws

abstract:
  In this paper we analyze the large time asymptotic behavior of the discrete
solutions of numerical approximation schemes for scalar hyperbolic conservation
laws. We consider three monotone conservative schemes that are consistent with
the one-sided Lipschitz condition (OSLC): Lax-Friedrichs, Engquist-Osher and
Godunov. We mainly focus on the inviscid Burgers equation, for which we know
that the large time behavior is of self-similar nature, described by a
two-parameter family of N-waves. We prove that, at the numerical level, the
large time dynamics depends on the amount of numerical viscosity introduced by
the scheme: while Engquist-Osher and Godunov yield the same N-wave asymptotic
behavior, the Lax-Friedrichs scheme leads to viscous self-similar profiles,
corresponding to the asymptotic behavior of the solutions of the continuous
viscous Burgers equation. The same problem is analyzed in the context of
self-similar variables that lead to a better numerical performance but to the
same dichotomy on the asymptotic behavior: N-waves versus viscous ones. We also
give some hints to extend the results to more general fluxes. Some numerical
experiments illustrating the accuracy of the results of the paper are also
presented.


title: Universality of the Stochastic Airy Operator

abstract:
  We introduce a new method for studying universality of random matrices. Let
T_n be the Jacobi matrix associated to the Dyson beta ensemble with uniformly
convex polynomial potential. We show that after scaling, T_n converges to the
Stochastic Airy operator. In particular, the top edge of the Dyson beta
ensemble and the corresponding eigenvectors are universal. As a byproduct, our
work leads to conjectured operator limits for the entire family of soft edge
distributions.


title: Weak controllability of second order evolution systems and applications

abstract:
  Controllability and observability are important properties of a distributed
paramater systems.The equivalence between the notion of exact observability and
exact controllability holds in general. In this work, we define a new notion of
controllability say weak which is related to some weak observability inequality
and we give the equivalence between.


title:
A multivariate spatial interpolation of airborne {\gamma}-ray data using
  the geological constraints

abstract:
  In this paper we present maps of K, eU, and eTh abundances of Elba Island
(Italy) obtained with a multivariate spatial interpolation of airborne
{\gamma}-ray data using the constraints of the geologic map. The radiometric
measurements were performed by a module of four NaI(Tl) crystals of 16 L
mounted on an autogyro. We applied the collocated cokriging (CCoK) as a
multivariate estimation method for interpolating the primary under-sampled
airborne {\gamma}-ray data considering the well-sampled geological information
as ancillary variables. A random number has been assigned to each of 73
geological formations identified in the geological map at scale 1:10,000. The
non-dependency of the estimated results from the random numbering process has
been tested for three distinct models. The experimental cross-semivariograms
constructed for radioelement-geology couples show well-defined co-variability
structures for both direct and crossed variograms. The high statistical
correlations among K, eU, and eTh measurements are confirmed also by the same
maximum distance of spatial autocorrelation. Combining the smoothing effects of
probabilistic interpolator and the abrupt discontinuities of the geological
map, the results show a distinct correlation between the geological formation
and radioactivity content. The contour of Mt. Capanne pluton can be
distinguished by high K, eU and eTh abundances, while different degrees of
radioactivity content identify the tectonic units. A clear anomaly of high K
content in the Mt. Calamita promontory confirms the presence of felsic dykes
and hydrothermal veins not reported in our geological map. Although we assign a
unique number to each geological formation, the method shows that the internal
variability of the radiometric data is not biased by the multivariate
interpolation.


title: On high order finite element spaces of differential forms

abstract:
  We show how the high order finite element spaces of differential forms due to
Raviart-Thomas-N\'edelec-Hiptmair fit into the framework of finite element
systems, in an elaboration of the finite element exterior calculus of
Arnold-Falk-Winther. Based on observations by Bossavit, we provide new low
order degrees of freedom. As an alternative to existing choices of bases, we
provide canonical resolutions in terms of scalar polynomials and Whitney forms.


title: The evolution of C and O abundances in stellar populations

abstract:
  Carbon and oxygen abundances in F and G main-sequence stars ranging in
metallicity from [Fe/H] = -1.6 to +0.5 are determined from a non-LTE analysis
of CI and OI atomic lines in high-resolution spectra. Both C and O are good
tracers of stellar populations; distinct trends of [C/Fe] and [O/Fe] as a
function of [Fe/H] are found for high- and low-alpha halo stars and for thick-
and thin-disk stars. These trends and that of [C/O] provide new information on
the nucleosynthesis sites of carbon and the time-scale for the chemical
enrichment of the various Galactic components.


title: Blow-up profile for the complex-valued semilinear wave equation

abstract:
  In this paper, we consider a blow-up solution for the complex-valued
semilinear wave equation with power nonlinearity in one space dimension. We
first characterize all the solutions of the associated stationary problem as a
two-parameter family. Then, we use a dynamical system formulation to show that
the solution in self-similar variables approaches some particular stationary
one in the energy norm, in the non-characteristic case. This gives the blow-up
profile for the original equation in the non-characteristic case. Our analysis
is not just a simple adaptation of the already handled real case. In
particular, there is one more neutral-direction in our problem, which we
control thanks to a modulation technique.


title:
Nested Punctual Hilbert Schemes and Commuting Varieties of Parabolic
  Subalgebras

abstract:
  It is known that the variety parametrizing pairs of commuting nilpotent
matrices is irreducible and that this provides a proof of the irreducibility of
the punctual Hilbert scheme in the plane. We extend this link to the nilpotent
commuting variety of parabolic subalgebras of $M\_n(\K)$ and to the punctual
nested Hilbert scheme. By this method, we obtain a lower bound on the dimension
of these moduli spaces. We characterize the numerical conditions under which
they are irreducible. In some reducible cases, we describe the irreducible
components and their dimension.


title:
Bose-Einstein Condensation on a Manifold with Nonnegative Ricci
  Curvature

abstract:
  The Bose-Einstein condensation for an ideal Bose gas and for a dilute weakly
interacting Bose gas in a manifold with nonnegative Ricci curvature is
investigated using the heat kernel and eigenvalue estimates of the Laplace
operator. The main focus is on the nonrelativistic gas. However, special
relativistic ideal gas is also discussed. The thermodynamic limit of the heat
kernel and eigenvalue estimates is taken and the results are used to derive
bounds for the depletion coefficient. In the case of a weakly interacting gas
Bogoliubov approximation is employed. The ground state is analyzed using heat
kernel methods and finite size effects on the ground state energy are proposed.
The justification of the c-number substitution on a manifold is given.


title:
Quantitative Analysis of the Tumor/Metastasis System and its Optimal
  Therapeutic Control

abstract:
  A mathematical model for time development of metastases and their
distribution in size and carrying capacity is presented. The model is used to
theoretically investigate anti-cancer therapies such as surgery and chemical
treatments (cytotoxic or anti-angiogenic), in monotherapy or in combination.
Quantification of the effect of surgery on the size distribution of metastatic
colonies is derived. For systemic therapies, emphasis is placed on the
differences between the treatment of an isolated lesion and a population of
metastases. Combination therapy is addressed, in particular the problem of the
drugs administration sequence. Theoretical optimal schedules are derived that
show the superiority of a metronomic administration scheme (defined as a
continuous administration of a given amount of drug spread during the whole
therapeutic cycle) on a classical Maximum Tolerated Dose scheme (where the dose
is given as a few concentrated administrations at the beginning of the cycle),
for the total metastatic burden in the organism.


title: Combinatorial spin structures on triangulated manifolds

abstract:
  This paper gives a combinatorial description of spin and spin^c-structures on
triangulated PL-manifolds of arbitrary dimension. These formulations of spin
and spin^c-structures are established primarily for the purpose of aiding in
computations. The novelty of the approach is we rely heavily on the naturality
of binary symmetric groups to avoid lengthy explicit constructions of
smoothings of PL-manifolds.


title:
Maximum Tolerated Dose Versus Metronomic Scheduling in the Treatment of
  Metastatic Cancers

abstract:
  Although optimal control theory has been used for the theoretical study of
anti-cancerous drugs scheduling optimization, with the aim of reducing the
primary tumor volume, the effect on metastases is often ignored. Here, we use a
previously published model for metastatic development to define an optimal
control problem at the scale of the entire organism of the patient. In silico
study of the impact of different scheduling strategies for anti-angiogenic and
cytotoxic agents (either in monotherapy or in combination) is performed to
compare a low-dose, continuous, metronomic administration scheme with a more
classical maximum tolerated dose schedule. Simulation results reveal
differences between primary tumor reduction and control of metastases but
overall suggest use of the metronomic protocol.


title: Metric and topological freedom for operator sequence spaces

abstract:
  In this paper we give description of free and cofree objects in the category
of operator sequence spaces. First we show that this category possess the same
duality theory as category of normed spaces, then with the aid of these results
we give complete description of metrically and topologically free and cofree
objects.


title:
Controlling adsorption of semiflexible polymers on planar and curved
  substrates

abstract:
  We study the adsorption of semiflexible polymers such as polyelectrolytes or
DNA on planar and curved substrates, e.g., spheres or washboard substrates via
short-range potentials using extensive Monte-Carlo simulations, scaling
arguments, and analytical transfer matrix techniques. We show that the
adsorption threshold of stiff or semiflexible polymers on a planar substrate
can be controlled by polymer stiffness: adsorption requires the highest
potential strength if the persistence length of the polymer matches the range
of the adsorption potential. On curved substrates, i.e., an adsorbing sphere or
an adsorbing washboard surface, the adsorption can be additionally controlled
by the curvature of the surface structure. The additional bending energy in the
adsorbed state leads to an increase of the critical adsorption strength, which
depends on the curvature radii of the substrate structure. For an adsorbing
sphere, this gives rise to an optimal polymer stiffness for adsorption, i.e., a
local minimum in the critical potential strength for adsorption, which can be
controlled by curvature. For two- and three-dimensional washboard substrates,
we identify the range of persistence lengths and the mechanisms for an
effective control of the adsorption threshold by the substrate curvature.


title: ACTIDS: An Active Strategy For Detecting And Localizing Network Attacks

abstract:
  In this work we investigate a new approach for detecting attacks which aim to
degrade the network's Quality of Service (QoS). To this end, a new
network-based intrusion detection system (NIDS) is proposed. Most contemporary
NIDSs take a passive approach by solely monitoring the network's production
traffic. This paper explores a complementary approach in which distributed
agents actively send out periodic probes. The probes are continuously monitored
to detect anomalous behavior of the network. The proposed approach takes away
much of the variability of the network's production traffic that makes it so
difficult to classify. This enables the NIDS to detect more subtle attacks
which would not be detected using the passive approach alone. Furthermore, the
active probing approach allows the NIDS to be effectively trained using only
examples of the network's normal states, hence enabling an effective detection
of zero-day attacks. Using realistic experiments, we show that an NIDS which
also leverages the active approach is considerably more effective in detecting
attacks which aim to degrade the network's QoS when compared to an NIDS which
relies solely on the passive approach. Lastly, we show that the false positives
rate remains very low even in the face of Byzantine faults.


title: Ultracold molecular collisions in combined electric and magnetic fields

abstract:
  We consider collisions of electric and magnetic polar molecules, taking the
OH radical as an example, subject to combined electric and magnetic static
fields. We show that the relative orientation of the fields has an important
effect on the collision processes for different fields magnitude at different
collision energies. This is due to the way the molecules polarize in the
combined electric and magnetic fields and hence the way the electric
dipole-dipole interaction rises. If OH molecules are confined in magnetic
quadrupole traps and if an electric field is applied, molecular collisions will
strongly depend on the position as well as the velocity of the molecules, and
consequences on the molecular dynamics are discussed.


title: Oracle inequalities for the lasso in the Cox model

abstract:
  We study the absolute penalized maximum partial likelihood estimator in
sparse, high-dimensional Cox proportional hazards regression models where the
number of time-dependent covariates can be larger than the sample size. We
establish oracle inequalities based on natural extensions of the compatibility
and cone invertibility factors of the Hessian matrix at the true regression
coefficients. Similar results based on an extension of the restricted
eigenvalue can be also proved by our method. However, the presented oracle
inequalities are sharper since the compatibility and cone invertibility factors
are always greater than the corresponding restricted eigenvalue. In the Cox
regression model, the Hessian matrix is based on time-dependent covariates in
censored risk sets, so that the compatibility and cone invertibility factors,
and the restricted eigenvalue as well, are random variables even when they are
evaluated for the Hessian at the true regression coefficients. Under mild
conditions, we prove that these quantities are bounded from below by positive
constants for time-dependent covariates, including cases where the number of
covariates is of greater order than the sample size. Consequently, the
compatibility and cone invertibility factors can be treated as positive
constants in our oracle inequalities.


title:
Strong interaction between plants induces circular barren patches: fairy
  circles

abstract:
  Vast landscapes extending from southern Angola, Namibia, and South Africa
exhibit localised barren patches of vegetation called fairy circles. They
consist of isolated or randomly distributed circular areas devoid of any
vegetation. They are surrounded by fringes of tall grasses and are embedded in
a sparse grassland on sandy soils. When the aridity increases, the size of the
fairy circles increases and can reach diameters up to 10m. Although several
hypotheses have been proposed, the origin of this phenomenon remains unsolved.
We show that a simple non-local model of plant ecology based on realistic
assumptions provides a quantitative explanation of this phenomenon. Fairy
circles result from strong interaction between interfaces connecting two
uniform covers: the uniform grassland and the bare states, and their
stabilisation is attributed to the Lorentzian-like non-local coupling that
models the competition between plants. The cause of their formation in thus
rather inherent to the vegetation dynamics. Our analysis explain how a circular
shape and fringes are formed, and how the aridity level influences the size of
the fairy circles. In agreement with field observation, these theoretical
findings, provide a link between a strong non-local interaction of plants and
the formation of stable fairy circles. Finally, we show that the proposed
mechanism is model-independent: indeed, it also applies to the
reaction-diffusion type of model that emphasises the influence of water
transport on the vegetation dynamics.


title:
A generalization of bounds for cyclic codes, including the HT and BS
  bounds

abstract:
  We use the algebraic structure of cyclic codes and some properties of the
discrete Fourier transform to give a reformulation of several classical bounds
for the distance of cyclic codes, by extending techniques of linear algebra. We
propose a bound, whose computational complexity is polynomial bounded, which is
a generalization of the Hartmann-Tzeng bound and the Betti-Sala bound. In the
majority of computed cases, our bound is the tightest among all known
polynomial-time bounds, including the Roos bound.


title: Linear programming duality for geometers

abstract:
  We present a geometric proof for the duality theorem of linear programming.
Besides being self-contained and simple, the present approach also provides a
transparent way for understanding this fundamental result.


title: Heat rectification effect of serially coupled quantum dots

abstract:
  The nonlinear thermoelectric properties of serially coupled quantum dots
(SCQDs) embedded in a nanowire connected to metallic electrodes are
theoretically studied in the Coulomb blockade regime. We demonstrate that the
electron heat current of SCQDs exhibit a direction-dependent behavior (heat
rectification) in an asymmetrical structure in which the electron Coulomb
interactions are significant. The phonon thermal conductivity of the nanowire
is also calculated, which is used to estimate the phonon heat current. Finally,
we discuss how to reduce phonon heat current to allow observation of electron
heat rectification behavior in the SCQD junction system in low temperature
regime ($\approx 3 K$).


title: Evolution of Yukawa couplings and quark flavour mixings in 2UED models

abstract:
  The evolution equations of the Yukawa couplings and quark mixings are derived
for the one-loop renormalization group equations in the two Universal Extra
Dimension Models (UED), that is six-dimensional models, compactified in
different possible ways to yield standard four space-time dimension. Different
possibilities for the matter fields are discussed, such as the case of bulk
propagating or localised brane fields. We discuss in both cases the evolution
of the Yukawa couplings, the Jarlskog parameter and the CKM matrix elements,
and we find that, for both scenarios, as we run up to the unification scale,
significant renormalization group corrections are present. We also discuss the
results of different observables of the five-dimensional UED model in
comparison with these six-dimensional models and the model dependence of the
results.


title: Relativistic Quantum Communication

abstract:
  In this Ph.D. thesis, I investigate the communication abilities of
non-inertial observers and the precision to which they can measure parametrized
states. I introduce relativistic quantum field theory with field quantisation,
and the definition and transformations of mode functions in Minkowski,
Schwarzschild and Rindler spaces. I introduce information theory by discussing
the nature of information, defining the entropic information measures, and
highlighting the differences between classical and quantum information. I
review the field of relativistic quantum information. We investigate the
communication abilities of an inertial observer to a relativistic observer
hovering above a Schwarzschild black hole, using the Rindler approximation. We
compare both classical communication and quantum entanglement generation of the
state merging protocol, for both the single and dual rail encodings. We find
that while classical communication remains finite right up to the horizon, the
quantum entanglement generation tends to zero. We investigate the observers'
abilities to precisely measure the parameter of a state that is communicated
between Alice and Rob. This parameter was encoded to either the amplitudes of a
single excitation state or the phase of a NOON state. With NOON states the dual
rail encoding provided greater precision, which is different to the results for
the other situations. The precision was maximum for a particular number of
excitations in the NOON state. We calculated the bipartite communication for
Alice-Rob and Alice-AntiRob beyond the single mode approximation. Rob and
AntiRob are causally disconnected counter-accelerating observers. We found that
Alice must choose in advance with whom, Rob or AntiRob she wants to create
entanglement using a particular setup. She could communicate classically to
both.


title: Random walk with priorities in communication-like networks

abstract:
  We study a model for a random walk of two classes of particles (A and B).
Where both species are present in the same site, the motion of A's takes
precedence over that of B's. The model was originally proposed and analyzed in
Maragakis et al., Phys. Rev. E 77, 020103 (2008); here we provide additional
results. We solve analytically the diffusion coefficients of the two species in
lattices for a number of protocols. In networks, we find that the probability
of a B particle to be free decreases exponentially with the node degree. In
scale-free networks, this leads to localization of the B's at the hubs and
arrest of their motion. To remedy this, we investigate several strategies to
avoid trapping of the B's: moving an A instead of the hindered B; allowing a
trapped B to hop with a small probability; biased walk towards non-hub nodes;
and limiting the capacity of nodes. We obtain analytic results for lattices and
networks, and discuss the advantages and shortcomings of the possible
strategies.


title: Quantum Transport With Two Interacting Conduction Channels

abstract:
  The transport properties of a conduction junction model characterized by two
mutually coupled channels that strongly differ in their couplings to the leads
are investigated. Models of this type describe molecular redox junctions (where
a level that is weakly coupled to the leads controls the molecular charge,
while a strongly coupled one dominates the molecular conduction), and electron
counting devices in which the current in a point contact is sensitive to the
charging state of a nearby quantum dot. Here we consider the case where
transport in the strongly coupled channel has to be described quantum
mechanically (covering the full range between sequential tunneling and
co-tunneling), while conduction through the weakly coupled channel is a
sequential process that could by itself be described by a simple master
equation. We compare the result of a full quantum calculation based on the
pseudoparticle non-equilibrium Green function method to that obtained from an
approximate mixed quantum-classical calculation, where correlations between the
channels are taken into account through either the averaged rates or the
averaged energy. We find, for the steady state current, that the approximation
based on the averaged rates works well in most of the voltage regime, with
marked deviations from the full quantum results only at the threshold for
charging the weekly coupled level. These deviations are important for accurate
description of the negative differential conduction behavior that often
characterizes redox molecular junctions in the neighborhood of this threshold.


title:
The potential of preprints to accelerate scholarly communication - A
  bibliometric analysis based on selected journals

abstract:
  This paper quantifies to which extent preprints in arXiv accelerate scholarly
communication. The following subject fields were investigated up to the year
2012: High Energy Physics (HEP), Mathematics, Astrophysics, Quantitative
Biology, and Library and Information Science (LIS). Publication and citation
data was downloaded from Scopus and matched with corresponding preprints in
arXiv. Furthermore, the INSPIRE HEP database was used to retrieve citation data
for papers related to HEP. The bibliometric analysis deals with the growth in
numbers of articles published having a previous preprint in arXiv and the
publication delay, which is defined as the chronological distance between the
deposit of a preprint in arXiv and its formal journal publication. Likewise,
the citation delay is analyzed, which describes the time it takes until the
first citation of preprints, and articles, respectively. Total citation numbers
are compared for sets of articles with a previous preprint and those without.
The results show that in all fields but biology a significant citation
advantage exists in terms of speed and citation rates for articles with a
previous preprint version on arXiv.


title:
CH+ depletion by atomic hydrogen: accuracy of new rates in
  photo-dominated and self-shielded environments

abstract:
  A detailed quantum analysis of a ionic reaction with a crucial role in the
ISM is carried out to generate ab initio reactive cross sections with a quantum
method. From them we obtain the corresponding CH+ depletion rates over a broad
range of temperatures. The new rates are further linked to a complex chemical
network that shows the evolution in time of the CH+ abundance in
photodissociation region (PDR) and molecular cloud (MC) environments.
  The evolutionary abundances of CH+ are given by numerical solutions of a
large set of coupled, first-order kinetics equations by employing the new
chemical package KROME. The differences found between all existing calculations
from low-T experiments are explained via a simple numerical model that links
the low-T cross section reductions to collinear approaches where nonadiabatic
crossings dominate. The analysis of evolutionary abundance of CH+ reveals that
the important region for the depletion reaction of this study is that above 100
K, hence showing that, at least for this reaction, the differences with the
existing low-temperature experiments are of essentially no importance within
the astrochemical environments. A detailed analysis of the chemical network
involving CH+ also shows that a slight decrease in the initial oxygen abundance
might lead to higher CH+ abundance since the main chemical carbon ion depletion
channel is reduced in efficiency. This simplified observation might provide an
alternative starting point to understand the problem of astrochemical models in
matching the observed CH+ abundances.


title: Cooperative effects in inelastic tunneling

abstract:
  Several aspects of intermolecular effects in molecular conduction have been
studied in recent years. These experimental and theoretical studies, made on
several setups of molecular conduction junctions, have focused on the
current-voltage characteristic that is usually dominated by the elastic
transmission properties of such junctions. In this paper we address cooperative
intermolecular effects in the inelastic tunneling signal calculated for simple
generic models of such systems. We find that peaks heights in the
inelasticspectrum may be affected by such cooperative effects even when direct
intermolecular interactions can be disregarded. This finding suggests that
comparing experimental results to calculations made on single-molecule
junctions should be done with care.


title:
FCC046: a candidate gaseous polar ring dwarf elliptical galaxy in the
  Fornax Cluster

abstract:
  FCC046 is a Fornax Cluster dwarf elliptical galaxy. Optical observations have
shown that this galaxy, besides an old and metal-poor stellar population, also
contains a very young centrally concentrated population and is actively forming
stars, albeit at a very low level. Here, we report on 21cm observations of
FCC046 with the Australia Telescope Compact Array (ATCA) which we conducted in
the course of a small survey of Fornax Cluster early-type dwarf galaxies. We
have discovered a ~10^7 Mo HI cloud surrounding FCC046. We show that the
presence of this significant gas reservoir offers a concise explanation for
this galaxy's optical morphological and kinematical properties. Surprisingly,
the HI gas, as evidenced by its morphology and its rotational motion around the
galaxy's optical major axis, is kinematically decoupled from the galaxy's
stellar body. This is the first time such a ring of gaseous material in
minor-axis rotation is discovered around a dwarf galaxy.


title:
New composition dependent cooling and heating curves for galaxy
  evolution simulations

abstract:
  In this paper, we present a new calculation of composition-dependent
radiative cooling and heating curves of low-density gas, intended primarily for
use in numerical simulations of galaxy formation and evolution. These curves
depend on only five parameters: temperature, density, redshift, [Fe/H], and
[Mg/Fe]. They are easily tabulated and can be efficiently interpolated during a
simulation.
  The ionization equilibrium of 14 key elements is determined for temperatures
between 10K and 10^9K and densities up to 100 amu/cm^3 taking into account
collisional and radiative ionization, by the cosmic UV background and an
interstellar radiation field, and by charge-transfer reactions. These elements,
ranging from H to Ni, are the ones most abundantly produced and/or released by
SNIa, SNII, and intermediate-mass stars. Self-shielding of the gas at high
densities by neutral Hydrogen is taken into account in an approximate way by
exponentially suppressing the H-ionizing part of the cosmic UV background for
HI densities above a threshold density of n_HI,crit=0.007 cm^-3. We discuss how
the ionization equilibrium, and the cooling and heating curves depend on the
physical properties of the gas.
  The main advantage of the work presented here is that, within the confines of
a well-defined chemical evolution model and adopting the ionization equilibrium
approximation, it provides accurate cooling and heating curves for a wide range
of physical and chemical gas properties, including the effects of
self-shielding. The latter is key to resolving the formation of cold, neutral,
high-density clouds suitable for star formation in galaxy simulations.


title: Optimal parameter estimation with a fixed rate of abstention

abstract:
  The problems of optimally estimating a phase, a direction, and the
orientation of a Cartesian frame (or trihedron) with general pure states are
addressed. Special emphasis is put on estimation schemes that allow for
inconclusive answers or abstention. It is shown that such schemes enable
drastic improvements, up to the extent of attaining the Heisenberg limit in
some cases, and the required amount of abstention is quantified. A general
mathematical framework to deal with the asymptotic limit of many qubits or
large angular momentum is introduced and used to obtain analytical results for
all the relevant cases under consideration. Parameter estimation with
abstention is also formulated as a semidefinite programming problem, for which
very efficient numerical optimization techniques exist.


title: Measurement of charm fragmentation fractions in photoproduction at HERA

abstract:
  The production of D^0, D^*+, D^+, D_s+ and Lambda_c^+ charm hadrons and their
antiparticles in ep scattering at HERA has been studied with the ZEUS detector,
using a total integrated luminosity of 372 pb^-1. The fractions of charm quarks
hadronising into a particular charm hadron were derived. In addition, the ratio
of neutral to charged D-meson production rates, the fraction of charged D
mesons produced in a vector state, and the stangeness-suppression factor have
been determined. The measurements have been performed in the photoproduction
regime. The charm hadrons were reconstructed in the range of transverse
momentum p_T >3.8 GeV and pseudorapidity |eta|<1.6. The charm fragmentation
fractions are compared to previous results from HERA and from e+e-experiments.
The data support the hypothesis that fragmentation is independent of the
production process.


title:
An extended SMLD approach for presumed probability density function in
  flamelet combustion model

abstract:
  This paper provides an extension of the standard flamelet progress variable
(FPV) approach for turbulent combustion, applying the statistically most likely
distribution (SMLD) framework to the joint PDF of the mixture fraction, Z, and
the progress variable, C. In this way one does not need to make any assumption
about the statistical correlation between Z and C and about the behaviour of
the mixture fraction, as required in previous FPV models. In fact, for
state-of-the-art models, with the assumption of very-fast-chemistry,Z is widely
accepted to behave as a passive scalar characterized by a $\beta$-distribution
function. Instead, the model proposed here, evaluates the most probable joint
distribution of Z and C without any assumption on their behaviour and provides
an effective tool to verify the adequateness of widely used hypotheses, such as
their statistical independence. The model is validated versus three well-known
test cases, namely, the Sandia flames. The results are compared with those
obtained by the standard FPV approach, analysing the role of the PDF functional
form on turbulent combustion simulations.


title:
A loss function approach to model specification testing and its relative
  efficiency

abstract:
  The generalized likelihood ratio (GLR) test proposed by Fan, Zhang and Zhang
[Ann. Statist. 29 (2001) 153-193] and Fan and Yao [Nonlinear Time Series:
Nonparametric and Parametric Methods (2003) Springer] is a generally applicable
nonparametric inference procedure. In this paper, we show that although it
inherits many advantages of the parametric maximum likelihood ratio (LR) test,
the GLR test does not have the optimal power property. We propose a generally
applicable test based on loss functions, which measure discrepancies between
the null and nonparametric alternative models and are more relevant to
decision-making under uncertainty. The new test is asymptotically more powerful
than the GLR test in terms of Pitman's efficiency criterion. This efficiency
gain holds no matter what smoothing parameter and kernel function are used and
even when the true likelihood function is available for the GLR test.


title:
Gravitational corrections to the scattering in a massless quantum
  electrodynamics

abstract:
  We discuss the role of gravitational corrections to the running of the
electric charge through the evaluation of scattering amplitudes of charged
particles in massless scalar electrodynamics. Computing the complete divergent
part of the S-matrix amplitude for two distinct scattering processes, we show
that quantum gravitational corrections do not alter the running behavior of the
electric charge. Our result does not exclude the possibility that the presence
of a second dimensional constant in the model (a cosmological constant or the
presence of massive particles) could alter this behavior, as was proposed in
earlier works.


title: Towards the rotating scalar-vacuum black holes

abstract:
  The problem of merging in black holes the rotation and a massless scalar
field is treated. It is argued in the comment that the Kerr-like and
Demianski-like metrics in General Relativity with a free massless scalar field
or in the free Brans-Dicke theory, claimed so far in the literature as an
application of the Newman-Janis algorithm, prove to be invalid. Finding the
missing stationary axisymmetric scalar-vacuum solution(s), containing the Kerr
one, is still urgent.


title: Asymptotic power of sphericity tests for high-dimensional data

abstract:
  This paper studies the asymptotic power of tests of sphericity against
perturbations in a single unknown direction as both the dimensionality of the
data and the number of observations go to infinity. We establish the
convergence, under the null hypothesis and contiguous alternatives, of the log
ratio of the joint densities of the sample covariance eigenvalues to a Gaussian
process indexed by the norm of the perturbation. When the perturbation norm is
larger than the phase transition threshold studied in Baik, Ben Arous and Peche
[Ann. Probab. 33 (2005) 1643-1697] the limiting process is degenerate, and
discrimination between the null and the alternative is asymptotically certain.
When the norm is below the threshold, the limiting process is nondegenerate,
and the joint eigenvalue densities under the null and alternative hypotheses
are mutually contiguous. Using the asymptotic theory of statistical
experiments, we obtain asymptotic power envelopes and derive the asymptotic
power for various sphericity tests in the contiguity region. In particular, we
show that the asymptotic power of the Tracy-Widom-type tests is trivial (i.e.,
equals the asymptotic size), whereas that of the eigenvalue-based likelihood
ratio test is strictly larger than the size, and close to the power envelope.


title:
Une famille d'applications lin\'eaires li\'ee \`a l'hypoth\`ese de
  Riemann g\'en\'eralis\'ee

abstract:
  We exhibit a family of linear operators related to the almost-periodic
approach for the generalized Riemann hypothesis.


title: Stringy Corrections to the Classical Tests of General Relativity

abstract:
  String theory imposes modifications to Einstein's equations of classical
general relativity. Consequently, we calculate the additional corrections to
the classical tests: the perihelion precession of Mercury, the deflection of
light rays by the sun, and the gravitational redshift which should be present
if these modified equations hold. In each case, we determine --- quite
consistently with expectations --- that the stringy effects are much too small
to be measured.


title:
Correla\c{c}\~ao de longa-dura\c{c}\~ao e anal\'ise bayesiana da
  evolu\c{c}\~ao temporal dos terremotos ao longo da falha de samambaia,
  nordeste do brasil

abstract:
  A Bayesian approach is adopted to analyze the sequence of seismic events and
their magnitudes near Jo\~ao C\^amara which occurred mainly from 1983 to 1998
along the Samambaia fault. In this work, we choose a Bayesian model for the
process of occurrence times conditional on the observed magnitude values
following the same procedure suggested by Stavrakakis and Tselentis (1987). The
model parameters are determined on the basis of historical and physical
information. We generate posterior samples from the joint posterior
distribution of the model parameters by using a variant of the
Metropolis-Hastings algorithm. We use the results in a variety of ways,
including the construction of pointwise posterior confidence bands for the
conditional intensity of the point process as a function of time, as well as, a
posterior distribuition as a function of the mean of occurrence per unit time.


title:
String Theory has no Isotropic Solution for the Modified Einstein's
  Equations without the Dilaton

abstract:
  We investigate the modification to Einstein's vacuum field equations which is
imposed by string theory when the dilaton field is ignored. Including the
cosmological constant in all calculations, we prove that such a theory of
gravity admits no static isotropic solution. We then show that any isotropic
solution of the equations in question must necessarily be static, therefore
proving that no isotropic solution exists for this stringy modification to
gravity.


title:
Complete classes of designs for nonlinear regression models and
  principal representations of moment spaces

abstract:
  In a recent paper Yang and Stufken [Ann. Statist. 40 (2012a) 1665-1685] gave
sufficient conditions for complete classes of designs for nonlinear regression
models. In this note we demonstrate that there is an alternative way to
validate this result. Our main argument utilizes the fact that boundary points
of moment spaces generated by Chebyshev systems possess unique representations.


title:
Structural Stability, Electronic, Magnetic and Optical Properties of
  Rectangular Graphene and Boron-Nitride Quantum Dots: Effects of Size,
  Substitution and Electric Field

abstract:
  Using density functional theory calculations, we have examined the structural
stability, electronic, magnetic and optical properties of rectangular shaped
quantum dots (QDs) of graphene (G), Boron Nitride (BN) and their hybrids.
Different hybrid QDs have been considered by substituting a GQD (BNQD) with
BN-pairs (carbon atoms) at different positions. Several parameters like size,
amount of substitution etc. have been varied for all these QDs (GQDs, BNQDs,
hybrid-QDs) to monitor the corresponding changes in their properties. Among the
considered parameters, we find that substitution can act as a powerful tool to
attain interesting properties with these QDs, for example, broad range of
absorption (~2000 nm) in the near infrared (NIR) region, spin-polarized
HOMO-LUMO gaps without the application of any external-bias etc., which are
highly required in the preparation of opto-electronic, electronic/spintronic
devices etc. Explanations have been given in details by varying different
factors, like, changing the position and amount of substitution, application of
external electric-field etc., to ensure the reliability of our results.


title:
Some Isoperimetric Inequalities and Eigenvalue Estimates in Weighted
  Manifolds

abstract:
  In this paper we prove general inequalities involving the weighted mean
curvature of compact submanifolds immersed in weighted manifolds. As a
consequence we obtain a relative linear isoperimetric inequality for such
submanifolds. We also prove an extrinsic upper bound to the first non zero
eigenvalue of the drift Laplacian on closed submanifolds of weighted manifolds.


title:
A short course on positive solutions of systems of ODEs via fixed point
  index

abstract:
  We shall firstly study the existence of one positive solution of a model
problem for one equation via the classical Krasnosel'ski\u\i{} fixed-point
theorem. Secondly we investigate how to handle this problem via the fixed point
index theory for compact maps. Thirdly we illustrate how this approach can be
tailored in order to deal with non-trivial solutions for systems of ODEs
subject to local BCs. The case of nonlocal and nonlinear BCs will also be
investigated. Finally we present some applications to the existence of radial
solutions of some systems of elliptic PDEs.


title:
Exciton condensation in quantum wells. Excitonic hydrodynamics.
  Autosolitons

abstract:
  The hydrodynamics equations for indirect excitons in the double quantum wells
are obtained taking into account 1) a possibility of an exciton condensed phase
formation, 2) the presence of a pumping, 3) the finite value of the exciton
lifetime, 4) the exciton scattering by defects.New types of solutions in the
form of bright and dark autsolitons are obtained for the exciton density. The
role of localized and free exciton states is analyzed in a formation of the
emission spectra.


title:
Orbital and physical parameters of eclipsing binaries from the ASAS
  catalogue - V. Investigation of subgiants and giants: the case of ASAS
  J010538-8003.7, ASAS J182510-2435.5, and V1980 Sgr

abstract:
  We present absolute physical and orbital parameters for three double-lined
detached eclipsing binary systems from the All Sky Automated Survey (ASAS)
catalogue with subgiant and giant components. These parameters were derived
from archival V-band ASAS photometry and new radial velocities. The radial
velocities were calculated from high quality optical spectra we obtained with
the 8.2 m Subaru/HDS, ESO 3.6 m/HARPS, 1.9 m Radcliffe/GIRAFFE, CTIO 1.5
m/CHIRON, and 1.2 m Euler/CORALIE using the two-dimensional cross-correlation
technique (TODCOR) and synthetic template spectra chosen for every system
separately as references.
  The physical and orbital parameters of the systems were derived with the
PHOEBE and JKTEBOP codes. We checked the evolutionary status of the systems
with several sets of isochrones and determined distances for each system. The
derived uncertainties for individual masses of ASAS J010538-8003.7, ASAS
J182510-2435.5, and V1980 Sgr components vary from 0.7% to 3.6% while the radii
are in the range 1% to 24%. For all of the investigated systems such a detailed
orbital and physical analysis is presented for the first time.


title: Matrix factorizations and higher residue pairings

abstract:
  The periodic cyclic homology of any proper dg category comes equipped with a
canonical pairing. We show that in the case of the dg category of matrix
factorizations of an isolated singularity the canonical pairing can be
identified with the so-called higher residue pairing on the twisted de Rham
cohomology of the singularity.


title:
Electronic structure and layer-resolved transmission of bilayer graphene
  nanoribbon in the presence of vertical fields

abstract:
  Electronic properties of bilayer graphene are distinct from both the
conventional two dimensional electron gas and monolayer graphene due to its
particular chiral properties and excitation charge carrier dispersions. We
study the effect of strain on the electronic structure, the edge-states and
charge transport of bilayer graphene nanoribbon at zero-temperature. We
demonstrate a valley polarized quantum Hall effect in biased bilayer graphene
when the system is subjected to a perpendicular magnetic field. In this system
a topological phase transition from a quantum valley Hall to a valley polarized
quantum Hall phase can occur by tuning the interplanar strain. Furthermore, we
study the layer-resolved transport properties by calculating the layer
polarized quantity by using the recursive Green's function technique and show
that the resulting layer polarized value confirms the obtained phases. These
predictions can be verified by experiments and our results demonstrate the
possibility for exploiting strained bilayer graphene in the presence of
external fields for electronics and valleytronics devices.


title:
Derivation of Hydrodynamics from the Hamiltonian description of particle
  systems

abstract:
  Hamiltonian particle systems may exhibit non-linear hydrodynamic phenomena as
the time evolution of the density fields of energy, momentum, and mass. In this
Letter, an exact equation describing the time evolution is derived assuming the
local Gibbs distribution at initial time. The key concept in the derivation is
an identity similar to the fluctuation theorems. The Navier-Stokes equation is
obtained as a result of simple perturbation expansions in a small parameter
that represents the scale separation.


title:
Surfactant Spreading on a Thin Liquid Film: Reconciling Models and
  Experiments

abstract:
  The spreading dynamics of surfactant molecules on a thin fluid layer is of
both fundamental and practical interest. A mathematical model formulated by
Gaver and Grotberg 1990 describing the spreading of a single layer of insoluble
surfactant has become widely accepted, and several experiments on axisymmetric
spreading have confirmed its predictions for both the height profile of the
free surface and the spreading exponent (the radius of the circular area
covered by surfactant grows as t^{1/4}). However, these prior experiments have
primarily utilized surfactant quantities exceeding (sometimes far exceeding) a
monolayer. In this paper, we report that this regime is characterized by a
mismatch between the timescales of the experiment and model, and additionally
find that the spatial distribution of surfactant molecules differs
substantially from the model prediction. For experiments performed in the
monolayer regime for which the model was developed, the surfactant layer is
observed to have a spreading exponent of less than 1/10, far below the
predicted value, and the surfactant distribution is also in disagreement. These
findings suggest that the model is inadequate for describing the spreading of
insoluble surfactants on thin fluid layers.


title: Tensor meson photoproduction as a final state interaction effect

abstract:
  The model is presented to describe the f_2(1270) meson photoproduction as a
result of pion-pion interactions in the final state. Treating tensor mesons as
objects dynamically created due to final state interactions is a convenient and
straightforward way to employ data from pi pi scattering like phase shifts and
inelasticities for description of (photo)production reactions while retaining
proper analytical structure of amplitudes, two particle unitarity and crossing
symmetry. The model presented here can provide experimentally testable
quantities like differential cross sections and pi pi mass distributions as
well as the strengths of partial waves corresponding to various f_2(1270)
helicities which are essential for partial wave analyses. It can also be used
to compute moments of angular distribution and spin density matrix elements
where partial wave interference effects are important.


title:
Fault-Tolerant Control of a 2 DOF Helicopter (TRMS System) Based on
  H_infinity

abstract:
  In this paper, a Fault-Tolerant control of 2 DOF Helicopter (TRMS System)
Based on H-infinity is presented. In particular, the introductory part of the
paper presents a Fault-Tolerant Control (FTC), the first part of this paper
presents a description of the mathematical model of TRMS, and the last part of
the paper presented and a polytypic Unknown Input Observer (UIO) is synthesized
using equalities and LMIs. This UIO is used to observe the faults and then
compensate them, in this part the shown how to design a fault-tolerant control
strategy for this particular class of non-linear systems.


title: Cannibal Animal Games: a new variant of Tic-Tac-Toe

abstract:
  This paper presents a new partial two-player game, called the \emph{cannibal
animal game}, which is a variant of Tic-Tac-Toe. The game is played on the
infinite grid, where in each round a player chooses and occupies free cells.
The first player Alice can occupy a cell in each turn and wins if she occupies
a set of cells, the union of a subset of which is a translated, reflected
and/or rotated copy of a previously agreed upon polyomino $P$ (called an
\emph{animal}). The objective of the second player Bob is to prevent Alice from
creating her animal by occupying in each round a translated, reflected and/or
rotated copy of $P$. An animal is a \emph{cannibal} if Bob has a winning
strategy, and a \emph{non-cannibal} otherwise. This paper presents some new
tools, such as the \emph{bounding strategy} and the \emph{punching lemma}, to
classify animals into cannibals or non-cannibals. We also show that the
\emph{pairing strategy} works for this problem.


title:
Comparative analysis of model-independent methods for exploring the
  nature of dark energy

abstract:
  We make a comparative analysis of the various independent methods proposed in
the literature for studying the nature of dark energy, using four different
mocks of SnIa data. In particular, we explore a generic principal components
analysis approach, the genetic algorithms, a series of approximations like
Pad\'e power law approximants, and various expansions in orthogonal
polynomials, as well as cosmography, and compare them with the usual fit to a
model with a constant dark energy equation of state w. We find that, depending
on the mock data, some methods are more efficient than others at distinguishing
the underlying model, although there is no universally better method.


title:
Supervised Topical Key Phrase Extraction of News Stories using
  Crowdsourcing, Light Filtering and Co-reference Normalization

abstract:
  Fast and effective automated indexing is critical for search and personalized
services. Key phrases that consist of one or more words and represent the main
concepts of the document are often used for the purpose of indexing. In this
paper, we investigate the use of additional semantic features and
pre-processing steps to improve automatic key phrase extraction. These features
include the use of signal words and freebase categories. Some of these features
lead to significant improvements in the accuracy of the results. We also
experimented with 2 forms of document pre-processing that we call light
filtering and co-reference normalization. Light filtering removes sentences
from the document, which are judged peripheral to its main content.
Co-reference normalization unifies several written forms of the same named
entity into a unique form. We also needed a "Gold Standard" - a set of labeled
documents for training and evaluation. While the subjective nature of key
phrase selection precludes a true "Gold Standard", we used Amazon's Mechanical
Turk service to obtain a useful approximation. Our data indicates that the
biggest improvements in performance were due to shallow semantic features, news
categories, and rhetorical signals (nDCG 78.47% vs. 68.93%). The inclusion of
deeper semantic features such as Freebase sub-categories was not beneficial by
itself, but in combination with pre-processing, did cause slight improvements
in the nDCG scores.


title:
Interacting partially directed self avoiding walk. From phase transition
  to the geometry of the collapsed phase

abstract:
  In this paper, we investigate a model for a $1+1$ dimensional
self-interacting and partially directed self-avoiding walk, usually referred to
by the acronym IPDSAW. The interaction intensity and the free energy of the
system are denoted by $\beta$ and $f$, respectively. The IPDSAW is known to
undergo a collapse transition at $\beta_c$. We provide the precise asymptotic
of the free energy close to criticality, that is we show that
$f(\beta_c-\epsilon)\sim \gamma \epsilon^{3/2}$ where $\gamma$ is computed
explicitly and interpreted in terms of an associated continuous model. We also
establish some path properties of the random walk inside the collapsed phase
$(\beta>\beta_c)$. We prove that the geometric conformation adopted by the
polymer is made of a succession of long vertical stretches that attract each
other to form a unique macroscopic bead, we identify the horizontal extension
of the random walk inside the collapsed phase and we establish the convergence
of the rescaled envelope of the macroscopic bead towards a deterministic Wulff
shape.


title: Model Vapor-Deposited Glasses: Growth Front and Composition Effects

abstract:
  A growing body of experimental work indicates that physical vapor deposition
provides an effective route for preparation of stable glasses, whose properties
correspond in some cases to those expected for glasses that have been aged for
thousands of years. In this work, model binary glasses are prepared in a
process inspired by physical vapor deposition, in which particles are
sequentially added to the free surface of a growing film. The resulting glasses
are shown to be more stable than those prepared by gradual cooling from the
liquid phase. However, it is also shown that the composition of the resulting
glass, which is difficult to control in physical vapor deposition simulations
of thin films, plays a significant role on the physical characteristics of the
material. That composition dependence leads to a re- evaluation of previous
results from simulations of thinner films than those considered here, where the
equivalent age of the corresponding glasses was overestimated. The simulations
presented in this work, which correspond to films that are approximately 38
molecular diameters thick, also enable analysis of the devitrification
mechanism of vapor-deposited glasses. Consistent with experiments, it is found
that this mechanism consists of a mobility front that propagates from the free
interface into the interior of the films. Eliminating surface mobility
eliminates this route of transformation into the supercooled liquid.


title:
On a polynomial transformation of hypergeometric equations, Heun's
  differential equation and exceptional Jacobi polynomials

abstract:
  This paper addresses a general method of polynomial transformation of
hypergeometric equations. Examples of some classical special equations of
mathematical physics are generated. Heun's equation and exceptional Jacobi
polynomials are also treated.


title: Key Phrase Extraction of Lightly Filtered Broadcast News

abstract:
  This paper explores the impact of light filtering on automatic key phrase
extraction (AKE) applied to Broadcast News (BN). Key phrases are words and
expressions that best characterize the content of a document. Key phrases are
often used to index the document or as features in further processing. This
makes improvements in AKE accuracy particularly important. We hypothesized that
filtering out marginally relevant sentences from a document would improve AKE
accuracy. Our experiments confirmed this hypothesis. Elimination of as little
as 10% of the document sentences lead to a 2% improvement in AKE precision and
recall. AKE is built over MAUI toolkit that follows a supervised learning
approach. We trained and tested our AKE method on a gold standard made of 8 BN
programs containing 110 manually annotated news stories. The experiments were
conducted within a Multimedia Monitoring Solution (MMS) system for TV and radio
news/programs, running daily, and monitoring 12 TV and 4 radio channels.


title: Relatively Prime Sets, Divisor Sums, and Partial Sums

abstract:
  For a nonempty finite set $A$ of positive integers, let $\gcd\left(A\right)$
denote the greatest common divisor of the elements of $A$. Let
$f\left(n\right)$ and $\Phi\left(n\right)$ denote, respectively, the number of
subsets $A$ of $\left\{1, 2, \ldots, n\right\}$ such that $\gcd\left(A\right) =
1$ and the number of subsets $A$ of $\left\{1, 2, \ldots, n\right\}$ such that
$\gcd\left(A\cup\left\{n\right\}\right) =1$. Let $D\left(n\right)$ be the
divisor sum of $f\left(n\right)$. In this article, we obtain partial sums of
$f\left(n\right)$, $\Phi\left(n\right)$ and $D\left(n\right)$. We also obtain a
combinatorial interpretation and a congruence property of $D\left(n\right)$. We
give open questions concerning $\Phi\left(n\right)$ and $D\left(n\right)$ at
the end of this article.


title:
Scalar fields and defect structures: perturbative procedure for
  generalized models

abstract:
  We develop a general procedure to deal with defect structures in generalized
models, described by a single real scalar field, in (1,1) spacetime dimensions.
The models that we consider have the standard kinetic and potential
contributions modified to include corrections that depend on a single small
parameters, used to control modification on the kinematics and the potential.
We start with standard model that engenders stable defect structures, and we
show how to obtain new structures for the generalized models. We examine
distinct aspects of the new deformed solutions, including linear stability. We
work with several distinct modifications, and we show how to make the new
defect structures stable, controlled by the parameter that modify the standard
theory. We illustrate the procedure with examples of current interest to high
energy physics.


title:
Electromagnetically induced vorticity control in a quantum fluid
  velocity field

abstract:
  A new method is reported by which it is possible to induce certain flux
configurations of desired characteristics via electromagnetic means into the
overall quantum probability current of a many-body system in the Madelung
hydrodynamic picture. Some indicative applications are also considered with
emphasis in HTC and gravitational wave research.


title: Experimental constraints on the spin and parity of the Z(4430)+

abstract:
  We perform a full amplitude analysis of B0 -> psi' K+ pi- decays, with psi'
-> mu+ mu- or e+ e-, to constrain the spin and parity of the Z(4430)-. The
J^P=1+ hypothesis is favored over the 0-, 1-, 2- and 2+ hypotheses at the
levels of 3.4 sigma, 3.7 sigma, 4.7 sigma and 5.1 sigma, respectively. The
analysis is based on a 711 fb^-1 data sample that contains 772x10^6 B B pairs,
collected at the Y(4S) resonance by the Belle detector at the asymmetric-energy
e+ e- collider KEKB.


title: PMU-based Voltage Instability Detection through Linear Regression

abstract:
  Timely recognition of voltage instability is crucial to allow for effective
control and protection interventions. Phasor measurements units (PMUs) can be
utilized to provide high sampling rate time-synchronized voltage and current
phasors suitable for wide-area voltage instability detection. However, PMU data
contains unwanted measurement errors and noise, which may affect the results of
applications using these measurements for voltage instability detection. The
aim of this article is to revisit a sensitivities calculation to detect voltage
instability by applying a method utilizing linear regression for preprocessing
PMU data. The methodology is validated using both real-time
hardware-in-the-loop simulation and real PMU measurements from Norwegian
network.


title:
Two-level system with broken inversion symmetry coupled to a quantum
  harmonic oscillator

abstract:
  We study the generalized Jaynes-Cummings model of quantum optics at the
inversion-symmetry-breaking and in the ultrastrong coupling regime. With the
help of a generalized multiphoton rotating-wave approximation, we study the
stationary solutions of the Schr\"{o}dinger equation. It is shown that the
problem is reduced to resonant interaction of two position-displaced harmonic
oscillators. Explicit expressions for the eigenstates and eigenvalues of
generalized Jaynes-Cummings Hamiltonian are presented. We exemplify our
physical model with analytical and numerical considerations regarding collapse
and revivals of the initial population of a two-level system and photon
distribution function at the direct multiphoton resonant coupling.


title: Classical Electrodynamics and Absolute Simultaneity

abstract:
  Maxwell's equations and the Lorentz force density are expressed using an
alternative simultaneity gauge. As a result, they describe electrodynamics for
an observer travelling with a constant velocity through an isotropic medium. If
desired, one may regard the isotropic medium as an absolute space. An observer
at rest in the medium may be referred to as a preferred observer. The medium
appears electrically polarized to the moving observer. Such an observer regards
the speed of light as anisotropic by convention while sharing absolute
simultaneity relations with the preferred observer.


title:
Survey on Instruction Selection: An Extensive and Modern Literature
  Review

abstract:
  Instruction selection is one of three optimisation problems involved in the
code generator backend of a compiler. The instruction selector is responsible
of transforming an input program from its target-independent representation
into a target-specific form by making best use of the available machine
instructions. Hence instruction selection is a crucial part of efficient code
generation.
  Despite on-going research since the late 1960s, the last, comprehensive
survey on the field was written more than 30 years ago. As new approaches and
techniques have appeared since its publication, this brings forth a need for a
new, up-to-date review of the current body of literature. This report addresses
that need by performing an extensive review and categorisation of existing
research. The report therefore supersedes and extends the previous surveys, and
also attempts to identify where future research should be directed.


title: Spacetime transformation acoustics

abstract:
  A recently proposed analogue transformation method has allowed the extension
of transformation acoustics to general spacetime transformations. We analyze
here in detail the differences between this new analogue transformation
acoustics (ATA) method and the standard one (STA). We show explicitly that STA
is not suitable for transformations that mix space and time. ATA takes as
starting point the acoustic equation for the velocity potential, instead of
that for the pressure as in STA. This velocity-potential equation by itself
already allows for some transformations mixing space and time, but not all of
them. We explicitly obtain the entire set of transformations that do not leave
its form invariant. It is in these cases that ATA shows its true potential,
allowing for building a transformation acoustics method that enables the full
range of spacetime transformations. We provide an example of an important
transformation which cannot be achieved with STA. Using this transformation, we
design and simulate an acoustic frequency converter via the ATA approach.
Furthermore, in those cases in which one can apply both the STA and ATA
approaches, we study the different transformational properties of the
corresponding physical quantities.


title: Brane-Worlds at the LHC: Branons and KK-gravitons

abstract:
  We study the possibility of testing some generic properties of Brane-World
scenarios at the LHC. In particular, we pay attention to KK-graviton and branon
production. Both signals can be dominant depending on the value of the brane
tension. We analyze the differences between these two signatures. Finally, we
use recent data in the single photon channel from the ATLAS collaboration to
constraint the parameter space of both phenomenologies.


title:
Probing the Pomeron structure using dijets and $\gamma$+jet events at
  the LHC

abstract:
  We consider hard diffractive events in proton-proton collisions at the LHC,
in which both protons escape the collision intact. In such double Pomeron
exchange processes, we propose to measure dijets and photon-jet final states,
and we show that it has the potential to pin down the Pomeron quark and gluon
contents, a crucial ingredient in the standard QCD description of hard
diffraction. By comparing with predictions of the soft color interaction
approach, we also show that more generally, the measurement of the photon-jet
to di-jet cross section ratio can put stringent test on the QCD dynamics at
play in diffractive processes in hadronic collisions.


title: Einstein, the reality of space, and the action-reaction principle

abstract:
  Einstein regarded as one of the triumphs of his 1915 theory of gravity ---
the general theory of relativity --- that it vindicated the action--reaction
principle, while Newtonian mechanics as well as his 1905 special theory of
relativity supposedly violated it. In this paper we examine why Einstein came
to emphasise this position several years after the development of general
relativity. Several key considerations are relevant to the story: the
connection Einstein originally saw between Mach's analysis of inertia and both
the equivalence principle and the principle of general covariance, the waning
of Mach's influence owing to de Sitter's 1917 results, and Einstein's detailed
correspondence with Moritz Schlick in 1920.


title:
Effects of crystal length on the angular spectrum of spontaneous
  parametric downconversion photon pairs

abstract:
  We present a theoretical and experimental analysis of the joint effects of
the transverse electric field distribution and of the nonlinear crystal
characteristics on the properties of photon pairs generated by spontaneous
parametric downconversion (SPDC). While it is known that for a sufficiently
short crystal the pump electric field distribution fully determines the joint
signal-idler properties, for longer crystals the nonlinear crystal properties
also play an important role. In this paper we present experimental measurements
of the angular spectrum (AS) and of the conditional angular spectrum (CAS) of
photon pairs produced by spontaneous parametric downconversion (SPDC), carried
out through spatially-resolved photon counting. In our experiment we control
whether or not the source operates in the short-crystal regime through the
degree of pump focusing, and explicitly show how the AS and CAS measurements
differ in these two regimes. Our theory provides an understanding of the
boundary between these two regimes and also predicts the corresponding
differing behaviors.


title:
Induced spin filtering in electron transmission through chiral molecular
  layers adsorbed on metals with strong spin-orbit coupling

abstract:
  Recent observations of considerable spin polarization in photoemission from
metal surfaces through monolayers of chiral molecules were followed by several
efforts to rationalize the results as the effect of spin-orbit interaction that
accompanies electronic motion on helical, or more generally strongly curved,
potential surfaces. In this paper we (a) argue, using simple models, that
motion in curved force-fields with the typical energies used and the
characteristic geometry of DNA cannot account for such observations; (b)
introduce the concept of induced spin filtering, whereupon selectivity in the
transmission of the electron orbital angular momentum can induce spin
selectivity in the transmission process provided there is strong spin-orbit
coupling in the substrate; and (c) show that the spin polarizability in the
tunneling current as well as the photoemission current from gold covered by
helical adsorbates can be of the observed order of magnitude. Our results can
account for most of the published observations that involved gold and silver
substrates, however recent results obtained with an aluminum substrate can be
rationalized within the present model only if strong spin-orbit coupling is
caused by the built-in electric field at the molecule-metal interface.


title:
From-Below Approximations in Boolean Matrix Factorization: Geometry and
  New Algorithm

abstract:
  We present new results on Boolean matrix factorization and a new algorithm
based on these results. The results emphasize the significance of
factorizations that provide from-below approximations of the input matrix.
While the previously proposed algorithms do not consider the possibly different
significance of different matrix entries, our results help measure such
significance and suggest where to focus when computing factors. An experimental
evaluation of the new algorithm on both synthetic and real data demonstrates
its good performance in terms of good coverage by the first k factors as well
as a small number of factors needed for exact decomposition and indicates that
the algorithm outperforms the available ones in these terms. We also propose
future research topics.


title: Periodic elastic nanodomains in ultrathin tetrogonal-like BiFeO3 films

abstract:
  We present a synchrotron grazing incidence x-ray diffraction analysis of the
domain structure and polar symmetry of highly strained BiFeO3 thin films grown
on LaAlO3 substrate. We revealed the existence of periodic elastic nanodomains
in the pure tetragonal-like BFO ultrathin films down to a thickness of 6 nm. A
unique shear strain accommodation mechanism is disclosed. We further
demonstrated that the periodicity of the nanodomains increases with film
thickness but deviates from the classical Kittel's square root law in ultrathin
thickness regime (6 - 30 nm). Temperature-dependent experiments also reveal the
disappearance of periodic modulation above 90C due to a MC-MA structural phase
transition.


title: Inferential vs. Dynamical Conceptions of Physics

abstract:
  I contrast two possible attitudes towards a given branch of physics: as
inferential (i.e., as concerned with an agent's ability to make predictions
given finite information), and as dynamical (i.e., as concerned with the
dynamical equations governing particular degrees of freedom). I contrast these
attitudes in classical statistical mechanics, in quantum mechanics, and in
quantum statistical mechanics; in this last case, I argue that the
quantum-mechanical and statistical-mechanical aspects of the question become
inseparable. Along the way various foundational issues in statistical and
quantum physics are (hopefully!) illuminated.


title: Recognition of Named-Event Passages in News Articles

abstract:
  We extend the concept of Named Entities to Named Events - commonly occurring
events such as battles and earthquakes. We propose a method for finding
specific passages in news articles that contain information about such events
and report our preliminary evaluation results. Collecting "Gold Standard" data
presents many problems, both practical and conceptual. We present a method for
obtaining such data using the Amazon Mechanical Turk service.


title: Observation of non-diffracting behavior at the single-photon level

abstract:
  We demonstrate the generation of non-diffracting heralded single photons,
i.e. which are characterized by a single-photon transverse intensity
distribution which remains essentially unchanged over a significant propagation
distance. For this purpose we have relied on the process of spontaneous
parametric downconversion (SPDC) for the generation of signal and idler photon
pairs, where our SPDC crystal is pumped by a Bessel-Gauss (BG) beam. Our
experiment shows that the well-understood non-diffracting behavior of a BG beam
may be directly mapped to the signal-mode, single photons heralded by the
detection of a single idler photon. In our experiment, the heralded single
photon is thus arranged to be non-diffracting without the need for projecting
its single-photon transverse amplitude, post-generation, in any manner.


title:
Stellar orbits and the survival of metallicity gradients in simulated
  dwarf galaxies

abstract:
  We present a detailed analysis of the formation, evolution, and possible
longevity of metallicity gradients in simulated dwarf galaxies. Specifically,
we investigate the role of potentially orbit-changing processes such as radial
stellar migration and dynamical heating in shaping or destroying these
gradients. We also consider the influence of the star formation density
threshold, investigating both a low and high value (0.1 amu/$cm^{3}$ - 100
amu/$cm^{3}$).
  The Nbody-SPH models that we use to self-consistently form and evolve dwarf
galaxies in isolation show that, in the absence of significant angular
momentum, metallicity gradients are gradually built up during the evolution of
the dwarf galaxy, by ever more centrally concentrated star formation adding to
the overall gradient. Once formed, they are robust, survive easily in the
absence of external disturbances and hardly decline over several Gyr, and they
agree well with observed metallicity gradients of dwarf galaxies in the Local
Group. The underlying orbital displacement of stars is quite limited in our
models, being of the order of only fractions of the half light radius over
time-spans of 5 to 10 Gyr in all star formation schemes. This is contrary to
the strong radial migration found in massive disc galaxies, caused by
scattering of stars off the corotation resonance of spiral structures. In the
dwarf regime the stellar body only seems to undergo mild dynamical heating, due
to the lack of long-lived spiral structures and/or discs.
  The density threshold has profound influences on the star formation mode of
the models, but only a minor influence on the evolution of metallicity
gradients. Increasing the threshold 1000-fold causes comparatively stronger
dynamical heating of the stellar body due to the increased turbulence and the
scattering of stars off dense gas clouds, but the effect remains very limited
in absolute terms.


title: Independent Component Analysis via Distance Covariance

abstract:
  This paper introduces a novel statistical framework for independent component
analysis (ICA) of multivariate data. We propose methodology for estimating and
testing the existence of mutually independent components for a given dataset,
and a versatile resampling-based procedure for inference. Independent
components are estimated by combining a nonparametric probability integral
transformation with a generalized nonparametric whitening method that
simultaneously minimizes all forms of dependence among the components.
U-statistics of certain Euclidean distances between sample elements are
combined in succession to construct a statistic for testing the existence of
mutually independent components. The proposed measures and tests are based on
both necessary and sufficient conditions for mutual independence. When
independent components exist, one may apply univariate analysis to study or
model each component separately. Univariate models may then be combined to
obtain a multivariate model for the original observations. We prove the
consistency of our estimator under minimal regularity conditions without
assuming the existence of independent components a priori, and all assumptions
are placed on the observations directly, not on the latent components. We
demonstrate the improvements of the proposed method over competing methods in
simulation studies. We apply the proposed ICA approach to two real examples and
contrast it with principal component analysis.


title:
Some unexplored features of the nonlinear compressive magnetoacoustic
  Alfvenic waves

abstract:
  The theory of nonlinear magnetoacoustic wave in the past has strictly been
focused on purely compressive features of the mode. We show that a complete set
of nonlinear equations necessarily includes both compressional and shear
components of the magnetic field. These two turn out to be described by exactly
the same nonlinear equations, which make the use of such a complete full set of
equations far less complicated than expected. Present results should
considerably enrich the theory of these waves by opening up new frontiers of
investigation and providing some completely new types of nonlinear solutions.


title: A propos d une nouvelle interpr\'etation du Caput variationis de Leibniz

abstract:
  The concept of caput variationis plays a fundamental role in Leibniz s
Dissertatio de Arte Combinatoria, published in 1666. Hereafter we propose an
interpretation of the caput based on the notion of induced character of a group
introduced par Georg Frobenius in 1900.


title: Reconciliation of High Energy Scale Models of Inflation with Planck

abstract:
  The inflationary cosmology paradigm is very successful in explaining the CMB
anisotropy to the percent level. Besides the dependence on the inflationary
model, the power spectra, spectral tilt and non-Gaussianity of the CMB
temperature fluctuations also depend on the initial state of inflation. Here,
we examine to what extent these observables are affected by our ignorance in
the initial condition for inflationary perturbations, due to unknown new
physics at a high scale $M$. For initial states that satisfy constraints from
backreaction, we find that the amplitude of the power spectra could still be
significantly altered, while the modification in bispectrum remains small. For
such initial states, $M$ has an upper bound of a few tens of $H$, with $H$
being the Hubble parameter during inflation. We show that for $M\sim 20 H$,
such initial states always (substantially) suppress the tensor to scalar ratio.
In particular we show that a general choice of initial conditions can
satisfactorily reconcile the simple $1/2 m^2 \phi^2$ chaotic model with the
Planck data.


title:
Self-assembly of shallow magnetic spots through strongly stratified
  turbulence

abstract:
  Recent studies have demonstrated that in fully developed turbulence, the
effective magnetic pressure of a large-scale field (non-turbulent plus
turbulent contributions) can become negative. In the presence of strongly
stratified turbulence, this was shown to lead to a large-scale instability that
produces spontaneous magnetic flux concentrations. Furthermore, using a
horizontal magnetic field, elongated flux concentrations with a strength of a
few per cent of the equipartition value were found. Here we show that a uniform
vertical magnetic field leads to circular magnetic spots of equipartition field
strengths. This could represent a minimalistic model of sunspot formation and
highlights the importance of two critical ingredients: turbulence and strong
stratification. Radiation, ionization, and supergranulation may be important
for realistic simulations, but are not critical at the level of a minimalistic
model of magnetic spot formation.


title:
Determinantal and eigenvalue inequalities for matrices with numerical
  ranges in a sector

abstract:
  Let $A = \pmatrix A_{11} & A_{12} \cr A_{21} & A_{22}\cr\pmatrix \in M_n$,
where $A_{11} \in M_m$ with $m \le n/2$, be such that the numerical range of
$A$ lies in the set $\{e^{i\varphi} z \in \IC: |\Im z| \le (\Re z) \tan
\alpha\}$, for some $\varphi \in [0, 2\pi)$ and $\alpha \in [0, \pi/2)$. We
obtain the optimal containment region for the generalized eigenvalue $\lambda$
satisfying $$\lambda \pmatrix A_{11} & 0 \cr 0 & A_{22}\cr\pmatrix x = \pmatrix
0 & A_{12} \cr A_{21} & 0\cr\pmatrix x \quad \hbox{for some nonzero} x \in
\IC^n,$$ and the optimal eigenvalue containment region of the matrix $I_m -
A_{11}^{-1}A_{12} A_{22}^{-1}A_{21}$ in case $A_{11}$ and $A_{22}$ are
invertible. From this result, one can show $|\det(A)| \le \sec^{2m}(\alpha)
|\det(A_{11})\det(A_{22})|$. In particular, if $A$ is a accretive-dissipative
matrix, then $|\det(A)| \le 2^m |\det(A_{11})\det(A_{22})|$. These affirm some
conjectures of Drury and Lin.


title:
Scheduling unit processing time arc shutdown jobs to maximize network
  flow over time: complexity results

abstract:
  We study the problem of scheduling maintenance on arcs of a capacitated
network so as to maximize the total flow from a source node to a sink node over
a set of time periods. Maintenance on an arc shuts down the arc for the
duration of the period in which its maintenance is scheduled, making its
capacity zero for that period. A set of arcs is designated to have maintenance
during the planning period, which will require each to be shut down for exactly
one time period. In general this problem is known to be NP-hard. Here we
identify a number of characteristics that are relevant for the complexity of
instance classes. In particular, we discuss instances with restrictions on the
set of arcs that have maintenance to be scheduled; series parallel networks;
capacities that are balanced, in the sense that the total capacity of arcs
entering a (non-terminal) node equals the total capacity of arcs leaving the
node; and identical capacities on all arcs.


title: Duality completion of higher derivative corrections

abstract:
  We present a new method for completing higher derivative corrections for
theories that exhibit duality symmetries under reduction. This proposal is
based on the observation that duality symmetry in the reduced theory highly
constrains the form of the unreduced theory. We apply this idea to closed
bosonic string theory and complete the Riemann squared term to simply derive
the known full tree-level effective action to order alpha'.


title: Computing the Greedy Spanner in Linear Space

abstract:
  The greedy spanner is a high-quality spanner: its total weight, edge count
and maximal degree are asymptotically optimal and in practice significantly
better than for any other spanner with reasonable construction time.
Unfortunately, all known algorithms that compute the greedy spanner of n points
use Omega(n^2) space, which is impractical on large instances. To the best of
our knowledge, the largest instance for which the greedy spanner was computed
so far has about 13,000 vertices.
  We present a O(n)-space algorithm that computes the same spanner for points
in R^d running in O(n^2 log^2 n) time for any fixed stretch factor and
dimension. We discuss and evaluate a number of optimizations to its running
time, which allowed us to compute the greedy spanner on a graph with a million
vertices. To our knowledge, this is also the first algorithm for the greedy
spanner with a near-quadratic running time guarantee that has actually been
implemented.


title:
Nonlinear time series analysis of Hyperion's rotation: photometric
  observations and numerical simulations

abstract:
  The case of Hyperion has been studied excesively due to the fact it is the
largest known celestial body of a highly aspherical shape. It also has a low
mass density and remains in a 4:3 orbital resonance with Titan. Its lightcurve,
obtained through photometric observations by (Klavetter 1989a,b), was initialy
used to show that Hyperion's rotation exhibits no periodicity. Herein it is
analyzed in the means of time series analysis. The Hurst Exponent was estimated
to be H=0.87, indicating a persistent behaviour. The largest Lyapunov Exponent
$\lambda_{max}$ unfortunately could not be given a reliable estimate because of
the shortness of the dataset, consisting 38 observational points. These results
are compared with numerical simulations, which gave a value H=0.88 for the
chaotic zone of the phase space. The Lyapunov time $T_{Lyap}=1/\lambda_{max}$
is about 30 days, which is roughly 1.5 times greater than the orbital period.
By conducting observations over a longer period an insight in the dynamical
features of the present rotational state is possible.


title: Colliding with G2 near the Galactic Centre: a geometrical approach

abstract:
  The object G2 will pass within nearly 100 au from Sgr A* in 2014. Due to its
very short periapse, the study of the dynamical evolution of this object in the
short-term future may offer some insight into the region surrounding the
supermassive black hole at the centre of the Galaxy. With this scenario in
mind, it has recently been proposed by Bartos et al. (arXiv:1302.3220) that,
prior to its perinigricon, G2 will likely experience multiple encounters with
members of the black hole and neutron-star populations believed to orbit near
the Galactic Centre. Here, we further explore this possibility and study the
general case for collisions with the G2 object using the latest orbital
solutions provided by Phifer et al. (arXiv:1304.5280) and Gillessen et al.,
(arXiv:1306.1374) and a Monte Carlo approach to estimate the minimum orbit
intersection distance (MOID) with G2 as a function of the orbital parameters of
the incoming body. Our results indicate that encounters at distances closer
than 100 au started to become statistically significant only during the last
few years or so. MOIDs under 100 au are statistically more probable for the
most dynamically cold orbits. If there is a population of objects moving in
low-inclination, low-eccentricity orbits around the central black hole, the
highest probability for a close encounter with G2 is found to be in the period
2014 January-March but enhanced activity due to encounters may start as early
as 2013 July-August.


title: Non-Veech surfaces in H^hyp(4) are generic

abstract:
  We show that every surface in H^hyp(4) is either a Veech surface or a generic
surface, i.e. its GL^+(2,R)-orbit is either a closed or a dense subset of
H^hyp(4) . The proof develops new techniques applicable in general to the
problem of classifying orbit closures, especially in low genus. Recent results
of Eskin-Mirzakhani-Mohammadi, Avila-Eskin-M\"oller, and the second author are
used.
  Combined with work of Matheus and the second author, a corollary is that
there are at most finitely many non-arithmetic Teichm\"uller curves (closed
orbits of surfaces not covering the torus) in H^hyp(4).


title:
Chiral properties of hematite ({\alpha}-Fe2O3) inferred from resonant
  Bragg diffraction using circularly polarized x-rays

abstract:
  Chiral properties of the two phases - collinear motif (below Morin transition
temperature, TM=250 K) and canted motif (above TM) - of magnetically ordered
hematite ({\alpha}-Fe2O3) have been identified in single crystal resonant x-ray
Bragg diffraction, using circular polarized incident x-rays tuned near the iron
K-edge. Magneto-electric multipoles, including an anapole, fully characterize
the high-temperature canted phase, whereas the low-temperature collinear phase
supports both parity-odd and parity-even multipoles that are time-odd. Orbital
angular momentum accompanies the collinear motif, while it is conspicuously
absent with the canted motif. Intensities have been successfully confronted
with analytic expressions derived from an atomic model fully compliant with
chemical and magnetic structures. Values of Fe atomic multipoles previously
derived from independent experimental data, are shown to be completely
trustworthy.


title:
Radiative feedback from protoplanets in self-gravitating protoplanetary
  discs

abstract:
  It is well known that massive protoplanetary disc are gravitationally
unstable beyond tens of AU from their parent star. The eventual fate of the
self-gravitating gas clumps born in the disc is currently not understood,
although the range of uncertainty is well known. If clumps migrate inward
rapidly, they are tidally disrupted, which may leave behind giant or
terrestrial like planets. On the other hand, if clumps migrate less rapidly,
they tend to accrete gas, becoming proto brown dwarfs or low mass companions to
the parent star. Here we argue that radiative feedback of contracting clumps
(protoplanets) on their discs is an important effect that has been overlooked
in previous calculations. We show analytically that temperature in clump's
vicinity may be high enough to support a quasi-static atmosphere if the clump
mass is below a critical value, $M_{\rm cr} \sim 6$ Jupiter masses ($M_J$).
This may arrest further gas accretion onto the clump and thus promote formation
of planets rather than low mass companions. We use numerical simulations to
evaluate these analytical conclusions by studying migration and accretion of
gas clumps as a function of their initial mass, $M_i$. Simulations neglecting
the radiative preheating effect show that gas clumps with mass less than $\sim
2 M_J$ migrate inward rapidly; more massive clumps result in low mass
companions. In contrast, simulations that include radiative preheating from the
clump show that clumps as massive as $8 M_J$ migrate inward rapidly and end up
tidally disrupted in the inner disc. We conclude that, with other parameters
being equal, previous simulations neglecting radiative feedback from
self-gravitating clumps over-estimated the population of brown dwarfs and low
mass stellar companions and under-estimated the population of planets.


title: A Multi-Engine Approach to Answer Set Programming

abstract:
  Answer Set Programming (ASP) is a truly-declarative programming paradigm
proposed in the area of non-monotonic reasoning and logic programming, that has
been recently employed in many applications. The development of efficient ASP
systems is, thus, crucial. Having in mind the task of improving the solving
methods for ASP, there are two usual ways to reach this goal: $(i)$ extending
state-of-the-art techniques and ASP solvers, or $(ii)$ designing a new ASP
solver from scratch. An alternative to these trends is to build on top of
state-of-the-art solvers, and to apply machine learning techniques for choosing
automatically the "best" available solver on a per-instance basis.
  In this paper we pursue this latter direction. We first define a set of
cheap-to-compute syntactic features that characterize several aspects of ASP
programs. Then, we apply classification methods that, given the features of the
instances in a {\sl training} set and the solvers' performance on these
instances, inductively learn algorithm selection strategies to be applied to a
{\sl test} set. We report the results of a number of experiments considering
solvers and different training and test sets of instances taken from the ones
submitted to the "System Track" of the 3rd ASP Competition. Our analysis shows
that, by applying machine learning techniques to ASP solving, it is possible to
obtain very robust performance: our approach can solve more instances compared
with any solver that entered the 3rd ASP Competition. (To appear in Theory and
Practice of Logic Programming (TPLP).)


title:
Implicit-Explicit Runge-Kutta schemes for hyperbolic systems with stiff
  relaxation and applications

abstract:
  In this paper we give an overview of Implicit-Explicit Runge-Kutta schemes
applied to hyperbolic systems with stiff relaxation. In particular, we focus on
some recent results on the uniform accuracy for hyperbolic systems with stiff
relaxation [6], and hyperbolic system with diffusive relaxation [7, 5, 4]. In
the latter case, we present an original application to a model problem arising
in Extended Thermodynamics.


title: Generalized Formalism in Gauge-Invariant Gravitational Perturbations

abstract:
  By use of the gauge-invariant variables proposed by Kodama and Ishibashi, we
obtain the most general perturbation equations in the $(m+n)$-dimensional
spacetime with a warped product metric. These equations do not depend on the
spectral expansions of the Laplace-type operators on the $n$-dimensional
Einstein manifold. These equations enable us to have a complete gauge-invariant
perturbation theory and a well-defined spectral expansion for all modes and the
gauge invariance is kept for each mode. By studying perturbations of some
projections of Weyl tensor in the case of $m=2$, we define three Teukolsky-like
gauge-invariant variables and obtain the perturbation equations of these
variables by considering perturbations of the Penrose wave equations in the
$(2+n)$-dimensional Einstein spectime. In particular, we find the relations
between the Teukolsky-like gauge-invariant variables and the Kodama-Ishibashi
gauge-invariant variables. These relations imply that the Kodama-Ishibashi
gauge-invariant variables all come from the perturbations of Weyl tensor of the
spacetime.


title: Picard Groups and Class Groups of Monoid Schemes

abstract:
  We define and study the Picard group of a monoid scheme and the class group
of a normal monoid scheme. To do so, we develop some ideal theory for (pointed
abelian) noetherian monoids, including primary decomposition and discrete
valuations. The normalization of a monoid turns out to be a monoid scheme, but
not always a monoid.


title: A link between feedback outflows and satellite galaxy suppression

abstract:
  We suggest a direct link between the two "missing" baryon problems of
contemporary galaxy formation theory: (1) that large galaxies are known to
contain too little gas and stars and (2) that too few dwarf satellite galaxies
are observed around large galaxies compared with cosmological simulations. The
former can be explained by invoking some energetic process -- most likely AGN
or star formation feedback -- which expels to infinity a significant fraction
of the gas initially present in the proto-galaxy, while the latter problem is
usually explained by star formation feedback inside the dwarf or tidal and ram
pressure stripping of the gas from the satellite galaxy by its parent. Here we
point out that the host galaxy "missing" baryons, if indeed ejected at
velocities of hundreds to a thousand km s$^{-1}$, must also affect smaller
satellite galaxies by stripping or shocking the gas there. We estimate the
fraction of gas removed from the satellites as a function of the satellite
galaxy's properties. Applying these results to a Milky Way like dark matter
halo, we find that this singular shock ram pressure stripping event may be
quite efficient in removing the gas from the satellites provided that they are
close enough. We also use the orbital and mass modelling data for eight
Galactic dwarf spheroidal (dSph) satellites, and find that it is likely that
many of them have been affected by the Galactic outflow. We point out that
galactic outflows of the host may also trigger a starburst in the satellite
galaxies by over-pressuring their gas discs. This process may be responsible
for the formation of the globular clusters observed in some of the Milky Way's
dSphs (e.g. the Fornax and Sagittarius dSphs).