title:
Deforming the theory lambda-phi-4 along the parameters and fields
  gradient flows

abstract:
  Considering the action for the theory $\lambda\phi^{4}$ for a massive scalar
bosonic field as an entropy functional on the space of coupling constants and
on the space of fields, we determine the gradient flows for the scalar field,
the mass, and the self-interaction parameter. When the flow parameter is
identified with the energy scale, we show that there exist phase transitions
between unbroken exact symmetry scenarios and spontaneous symmetry breaking
scenarios at increasingly high energies. Since a non-linear heat equation
drives the scalar field through a {\it reaction-diffusion} process, in general
the flows are not reversible, mimicking the renormalization group flows of the
$c$-theorem; the deformation of the field at increasingly high energies can be
described as non-linear traveling waves, or solitons associated to self-similar
solutions


title: Collapse of quasi-two-dimensional wet granular columns

abstract:
  This paper deals with the experimental characterization of the collapse of
wet granular columns in the pendular state, with the purpose of collecting data
on triggering and jamming phenomena in wet granular media. The final deposit
shape and the runout dynamics were studied for samples of glass beads, varying
particle diameter, liquid surface tension, and liquid amount. We show how the
runout distance decreases with increasing water amount (reaching a plateau for
$w>1 \%$) and increases with increasing Bond number, while the top and toe
angles and the final deposit height increase with increasing water amount and
decrease with decreasing Bond number. Dimensional analysis allowed to discuss
possible scalings for the runout length and the top and toe angles: a
satisfying scaling was found, based on the combination of Bond number and
liquid amount.


title:
On the Well-posedness of Magnetohydrodynamics Equations for
  Incompressible Electrically-Conducting Fluids

abstract:
  It is shown that the Cauchy problem of the equations in magnetohydrodynamics
in the whole space is globally well-posed for any initial smooth and localized
data. In general, the mathematical structure of solution shows that the coupled
magnetic-vortical field has the characters of turbulence, if the initial data
exceed certain size. In particular, if a strong magnetic force dominates the
flow evolution, the current density possesses a cubic non-linearity. The
solution of the non-linear problem has been constructed and has been expressed
as an infinite series.


title:
Short-range correlation effects on the nuclear matrix element of
  neutrinoless double-$\beta$ decay

abstract:
  We report the results of a calculation of the nuclear matrix element of
neutrinoless double-$\beta$ decay of $^{48}$Ca, carried out taking into account
nucleon-nucleon correlations in both coordinate- and spin-space. Our numerical
results, obtained using nuclear matter correlation functions, suggest that
inclusion of correlations leads to a $\sim$ $20\%$ decrease of the matrix
element, with respect to the shell model prediction. This conclusion is
supported by the results of an independent calculation, in which correlation
effects are taken into account using the spectroscopic factors of $^{48}$Ca
obtained from an {\em ab intitio} many body approach.


title: Property (gw) for tensor product and left-right multiplication operators

abstract:
  Given Banach spaces $X$ and $Y$ and operators $A\in B(X)$ and $B\in B(Y)$,
property $(gw)$ does not in general transfer from $A$ and $B$ to the tensor
product operator $A\otimes B\in B(X\overline{\otimes} Y)$ or to the elementary
operator defined by $A$ and $B$, $\tau_{AB}=L_AR_B\in B(B(Y,X))$. In this
article necessary and sufficient conditions ensuring that property $(gw)$
transfers from $A$ and $B$ to $A\otimes B$ and to $\tau_{AB}$ will be given.


title: On Chiral Symmetry Breaking, Topology and Confinement

abstract:
  We start with the relation between the chiral symmetry breaking and gauge
field topology. New lattice result further enhance the notion of Zero Mode
Zone, a very narrow strip of states with quasizero Dirac eigenvalues. Then we
move to the issue of "origin of mass" and Brown-RHo scaling: a number of
empirical facts contradicts to the idea that masses of quarks and such hadrons
as $\rho,N$ decrease near $T_c$.
  We argue that while at $T=0$ the main contribution to the effective quark
mass is chirally odd $m_{\snchi}$, near $T_c$ it rotates to chirally-even
component $m_\chi$, because "infinite clusters" of topological solitons gets
split into finite ones. Recent progress in understanding of topology require
introduction of nonzero holonomy $<A_0>\neq 0$, which splits instantons into
$N_c$ (anti)selfdual "instanton-dyons". Qualitative progress, as well as first
numerical studios of the dyon ensemble are reported. New connections between
chiral symmetry breaking and confinement are recently understood, since
instanton-dyons generates holonomy potential with a minimum at confining value,
if the ensemble is dense enough.


title:
Raman-gain induced loss-compensation in
  whispering-gallery-microresonators and single-nanoparticle detection with
  whispering-gallery Raman-microlasers

abstract:
  Recently optical whispering-gallery-mode resonators (WGMRs) have emerged as
promising platforms to achieve label-free detection of nanoscale objects and to
reach single molecule sensitivity. The ultimate detection performance of WGMRs
are limited by energy dissipation in the material they are fabricated from. Up
to date, to improve detection limit, either rare-earth ions are doped into the
WGMR to compensate losses or plasmonic resonances are exploited for their
superior field confinement. Here, we demonstrate, for the first time, enhanced
detection of single-nanoparticle induced mode-splitting in a silica WGMR via
Raman-gain assisted loss-compensation and WGM Raman lasing. Notably, we
detected and counted individual dielectric nanoparticles down to a record low
radius of 10 nm by monitoring a beatnote signal generated when split Raman
lasing lines are heterodyne-mixed at a photodetector. This dopant-free scheme
retains the inherited biocompatibility of silica, and could find widespread use
for sensing in biological media. It also opens the possibility of using
intrinsic Raman or parametric gain in other systems, where dissipation hinders
the progress of the field and limits applications.


title: Variance-based control of regime shifts: bistability and oscillations

abstract:
  A variety of real world and experimental systems can display a drastic regime
shift, as the evolution in one its paramaters crosses a threshold value.
Assimilation of such a transition with a bifurcation has allowed to identify so
called "early warning signals", at the level of the time series generated by
the system underscope. The literature in early warning detection methods is
currently expanding and their potential for practical applicability is being
discussed in different contexts. In this work, we elaborate on the use of the
variance of a system variable, which constitutes the simplest early warning
indicator, to gain control on the long-term dynamics of the system, while
extending an exploitation phase. In particular, we address the cases of the
cusp and Hopf normal forms, as prototypical examples of bistability and
oscillations. Our results provide insights on the interplay between the
time-scale for the system observation, the degree of sensitivity of the control
feedback and the intensity of the random perturbations, in shaping the
long-term control efficiency.


title:
Enhancement of jet quenching around phase transition: result from the
  dynamical holographic model

abstract:
  The phase transition and jet quenching parameter ${\hat q}$ have been
investigated in the framework of dynamical holographic QCD model. It is found
that both the trace anomaly and the ratio of the jet quenching parameter over
cubic temperature ${\hat q}/T^3$ show a peak around the critical temperature
$T_c$, and the ratio of jet quenching parameter over entropy density ${\hat
q}/s$ sharply rises at $T_c$. This indicates that the jet quenching parameter
can characterize the phase transition. The effect of jet quenching parameter
enhancement around phase transition on nuclear modification factor $R_{AA}$ and
elliptic flow $v_2$ have also been analyzed, and it is found that the
temperature dependent jet quenching parameter from dynamical holographic QCD
model can considerably improve the description of jet quenching azimuthal
anisotropy as compared with the conformal case.


title: SPIRE Point Source Photometry

abstract:
  The different algorithms appropriate for point source photometry on data from
the SPIRE instrument on-board the Herschel Space Observatory, within the
Herschel Interactive Processing Environment (HIPE) are compared. Point source
photometry of a large ensemble of standard calibration stars and dark sky
observations is carried out using the 4 major methods within HIPE:
SUSSEXtractor, DAOphot, the SPIRE Timeline Fitter and simple Aperture
Photometry. Colour corrections and effective beam areas as a function of the
assumed source spectral index are also included to produce a large number of
photometric measurements per individual target, in each of the 3 SPIRE bands
(250, 350, 500um), to examine both the accuracy and repeatability of each of
the 4 algorithms. It is concluded that for flux densities down to the level of
30mJy that the SPIRE Timeline Fitter is the method of choice. However, at least
in the 250 and 350um bands, all 4 methods provide photometric repeatability
better than a few percent down to at approximately 100mJy. The DAOphot method
appears in many cases to have a systematic offset of ~8% in all SPIRE bands
which may be indicative of a sub-optimal aperture correction. In general,
aperture photometry is the least reliable method, i.e. largest scatter between
observations, especially in the longest wavelength band. At the faintest
fluxes, <30mJy, SUSSEXtractor or DAOphot provide a better alternative to the
Timeline Fitter.


title: Milnor-Moore Categories and Monadic Decomposition

abstract:
  In this paper Hom-Lie algebras, Lie color algebras, Lie superalgebras and
other type of generalized Lie algebras are recovered by means of an iterated
construction, known as monadic decomposition of functors, which is based on
Eilenberg-Moore categories. To this aim we introduce the notion of Milnor-Moore
category as a monoidal category for which a Milnor-Moore type Theorem holds. We
also show how to lift the property of being a Milnor-Moore category whenever a
suitable monoidal functor is given and we apply this technique to provide
examples.


title: Crowd Research at School: Crossing Flows

abstract:
  It has become widely known that when two flows of pedestrians cross stripes
emerge spontaneously by which the pedestrians of the two walking directions
manage to pass each other in an orderly manner. In this work, we report about
the results of an experiment on crossing flows which has been carried out at a
German school. These results include that previously reported high flow volumes
on the crossing area can be confirmed. The empirical results are furthermore
compared to the results of a simulation model which succesfully could be
calibrated to catch the specific properties of the population of participants.


title: Automated Code Generation for Lattice Quantum Chromodynamics and beyond

abstract:
  We present here our ongoing work on a Domain Specific Language which aims to
simplify Monte-Carlo simulations and measurements in the domain of Lattice
Quantum Chromodynamics. The tool-chain, called Qiral, is used to produce
high-performance OpenMP C code from LaTeX sources. We discuss conceptual issues
and details of implementation and optimization. The comparison of the
performance of the generated code to the well-established simulation software
is also made.


title: Herschel SPIRE FTS Spectral Mapping Calibration

abstract:
  The Herschel SPIRE Fourier transform spectrometer (FTS) performs spectral
imaging in the 447-1546 GHz band. It can observe in three spatial sampling
modes: sparse mode, with a single pointing on sky, or intermediate or full
modes with 1 and 1/2 beam spacing, respectively. In this paper, we investigate
the uncertainty and repeatability for fully sampled FTS mapping observations.
The repeatability is characterised using nine observations of the Orion Bar.
Metrics are derived based on the ratio of the measured intensity in each
observation compared to that in the combined spectral cube from all
observations. The mean relative deviation is determined to be within 2%, and
the pixel-by-pixel scatter is ~7%. The scatter increases towards the edges of
the maps. The uncertainty in the frequency scale is also studied, and the
spread in the line centre velocity across the maps is found to be ~15 km/s.
Other causes of uncertainty are also discussed including the effect of pointing
and the additive uncertainty in the continuum.


title: Order parameter profiles in presence of topological defect lines

abstract:
  We consider the broken phase of the n-vector model in n+1 dimensions with
boundary conditions enforcing the presence of topological defect lines (Ising
domain walls, XY vortex lines, and so on), and use field theory to argue an
exact expression for the order parameter.


title: An inverse problem for self-adjoint positive Hankel operators

abstract:
  For a sequence $\{\alpha_n\}_{n=0}^\infty$, we consider the Hankel operator
$\Gamma_\alpha$, realised as the infinite matrix in $\ell^2$ with the entries
$\alpha_{n+m}$. We consider the subclass of such Hankel operators defined by
the "double positivity" condition $\Gamma_\alpha\geq0$,
$\Gamma_{S^*\alpha}\geq0$; here $S^*\alpha$ is the shifted sequence
$\{\alpha_{n+1}\}_{n=0}^\infty$. We prove that in this class, the sequence
$\alpha$ is uniquely determined by the spectral shift function $\xi_\alpha$ for
the pair $\Gamma_\alpha^2$, $\Gamma_{S^*\alpha}^2$. We also describe the class
of all functions $\xi_\alpha$ arising in this way and prove that the map
$\alpha\mapsto\xi_\alpha$ is a homeomorphism in appropriate topologies.


title:
Relative pointing offset analysis of calibration targets with repeated
  observations with Herschel-SPIRE Fourier-Transform Spectrometer

abstract:
  We present a method to derive the relative pointing offsets for SPIRE
Fourier-Transform Spectrometer (FTS) solar system object (SSO) calibration
targets, which were observed regularly throughout the Herschel mission. We
construct ratios of the spectra for all observations of a given source with
respect to a reference. The reference observation is selected iteratively to be
the one with the highest observed continuum. Assuming that any pointing offset
leads to an overall shift of the continuum level, then these ratios represent
the relative flux loss due to mispointing. The mispointing effects are more
pronounced for a smaller beam, so we consider only the FTS short wavelength
array (SSW, 958-1546 GHz) to derive a pointing correction. We obtain the
relative pointing offset by comparing the ratio to a grid of expected losses
for a model source at different distances from the centre of the beam, under
the assumption that the SSW FTS beam can be well approximated by a Gaussian. In
order to avoid dependency on the point source flux conversion, which uses a
particular observation of Uranus, we use extended source flux calibrated
spectra to construct the ratios for the SSOs. In order to account for continuum
variability, due to the changing distance from the Herschel telescope, the SSO
ratios are normalised by the expected model ratios for the corresponding
observing epoch. We confirm the accuracy of the derived pointing offset by
comparing the results with a number of control observations, where the actual
pointing of Herschel is known with good precision. Using the method we derived
pointing offsets for repeated observations of Uranus (including observations
centred on off-axis detectors), Neptune, Ceres and NGC7027. The results are
used to validate and improve the point-source flux calibration of the FTS.


title: Scaling Laws for the Slip Velocity in Dense Granular Flows

abstract:
  In this Letter, the 2-dimensional dense flow of polygonal particles on an
incline with a flat frictional inferior boundary is analyzed by means of
contact dynamics discrete element simulations, in order to develop boundary
conditions for continuum models of dense granular flows. We show the evidence
that the global slip phenomenon deviates significantly from simple sliding: a
finite slip velocity is generally found for shear forces lower than the sliding
threshold for particle-wall contacts. We determined simple scaling laws for the
dependence of the slip velocity on shear rate, normal and shear stresses, and
material parameters.The importance of a correct determination of the slip at
the base of the incline, which is crucial for the calculation of flow rates, is
discussed in relation to natural flows.


title:
Herschel SPIRE Fourier Transform Spectrometer: Calibration of its
  Bright-source Mode

abstract:
  The Fourier Transform Spectrometer (FTS) of the Spectral and Photometric
Imaging REceiver (SPIRE) on board the ESA Herschel Space Observatory has two
detector setting modes: (a) a nominal mode, which is optimized for observing
moderately bright to faint astronomical targets, and (b) a bright-source mode
recommended for sources significantly brighter than 500 Jy, within the SPIRE
FTS bandwidth of 446.7-1544 GHz (or 194-671 microns in wavelength), which
employs a reduced detector responsivity and out-of-phase analog signal
amplifier/demodulator. We address in detail the calibration issues unique to
the bright-source mode, describe the integration of the bright-mode data
processing into the existing pipeline for the nominal mode, and show that the
flux calibration accuracy of the bright-source mode is generally within 2% of
that of the nominal mode, and that the bright-source mode is 3 to 4 times less
sensitive than the nominal mode.


title: Letter of Intent: The Precision IceCube Next Generation Upgrade (PINGU)

abstract:
  The Precision IceCube Next Generation Upgrade (PINGU) is a proposed
low-energy in-fill array of the IceCube Neutrino Observatory. Leveraging
technology proven with IceCube, PINGU will feature the world's largest
effective volume for neutrinos at an energy threshold of a few GeV, improving
the sensitivity to several aspects of neutrino oscillation physics at modest
cost. With its unprecedented statistical sample of low-energy atmospheric
neutrinos, PINGU will have highly competitive sensitivity to $\nu_{\mu}$
disappearance, the $\theta_{23}$ octant, and maximal mixing, will make the
world's best $\nu_{\tau}$ appearance measurement, allowing a unique probe of
the unitarity of the PMNS mixing matrix, and will be able to distinguish the
neutrino mass ordering at $3\sigma$ significance with less than 4 years of
data. PINGU can also extend the indirect search for solar WIMP dark matter
complimentary to the on-going and planned direct dark matter experiments. At
the lower end of the energy range, PINGU may use neutrino tomography to
directly probe the composition of the Earth's core. With its increased module
density, PINGU will improve IceCube's sensitivity to galactic supernova
neutrino bursts and enable it to extract the neutrino energy spectral shape.

categories: physics.ins-det astro-ph.HE astro-ph.IM hep-ex


title: Herschel SPIRE FTS telescope model correction

abstract:
  Emission from the Herschel telescope is the dominant source of radiation for
the majority of SPIRE Fourier transform spectrometer (FTS) observations,
despite the exceptionally low emissivity of the primary and secondary mirrors.
Accurate modelling and removal of the telescope contribution is, therefore, an
important and challenging aspect of FTS calibration and data reduction
pipeline. A dust-contaminated telescope model with time invariant mirror
emissivity was adopted before the Herschel launch. However, measured FTS
spectra show a clear evolution of the telescope contribution over the mission
and strong need for a correction to the standard telescope model in order to
reduce residual background (of up to 7 Jy) in the final data products.
Systematic changes in observations of dark sky, taken over the course of the
mission, provide a measure of the evolution between observed telescope emission
and the telescope model. These dark sky observations have been used to derive a
time dependent correction to the telescope emissivity that reduces the
systematic error in the continuum of the final FTS spectra to ~0.35 Jy.


title:
In-medium QCD sum rules for D mesons: A projection method for higher
  order contributions

abstract:
  D mesons serve as excellent probes of hot and/or dense strongly interacting
matter. They can provide insight into the restoration of chiral symmetry. The
chiral condensate as well as other chirally odd condensates, such as certain
four-quark condensates, are linked to order parameters of spontaneous chiral
symmetry breaking. Thus, the evaluation of these higher order condensate
contributions in the framework of QCD sum rules is of high interest. We present
a general method for projecting Lorentz indices of ground state expectation
values providing a crucial step towards a comprehensive calculation of higher
order corrections to the operator product expansion of hadrons, especially D
mesons, in a strongly interacting medium.


title: Herschel SPIRE FTS Relative Spectral Response Calibration

abstract:
  Herschel/SPIRE Fourier transform spectrometer (FTS) observations contain
emission from both the Herschel Telescope and the SPIRE Instrument itself, both
of which are typically orders of magnitude greater than the emission from the
astronomical source, and must be removed in order to recover the source
spectrum. The effects of the Herschel Telescope and the SPIRE Instrument are
removed during data reduction using relative spectral response calibration
curves and emission models. We present the evolution of the methods used to
derive the relative spectral response calibration curves for the SPIRE FTS. The
relationship between the calibration curves and the ultimate sensitivity of
calibrated SPIRE FTS data is discussed and the results from the derivation
methods are compared. These comparisons show that the latest derivation methods
result in calibration curves that impart a factor of between 2 and 100 less
noise to the overall error budget, which results in calibrated spectra for
individual observations whose noise is reduced by a factor of 2-3, with a gain
in the overall spectral sensitivity of 23% and 21% for the two detector bands,
respectively.


title:
Parametric argument principle and its applications to CR functions and
  manifolds

abstract:
  A version of the argument principle is established for varieties of
holomorphic mappings from the unit disc to $\mathbb C^n,$ parametrized by
points of real manifolds. Applications to characterization of CR functions and
estimating CR dimensions of real submanifolds in $\mathbb C^n$ are given.


title:
Enhancement performance of road recognition system of autonomous robots
  in shadow scenario

abstract:
  Road region recognition is a main feature that is gaining increasing
attention from intellectuals because it helps autonomous vehicle to achieve a
successful navigation without accident. However, different techniques based on
camera sensor have been used by various researchers and outstanding results
have been achieved. Despite their success, environmental noise like shadow
leads to inaccurate recognition of road region which eventually leads to
accident for autonomous vehicle. In this research, we conducted an
investigation on shadow and its effects, optimized the road region recognition
system of autonomous vehicle by introducing an algorithm capable of detecting
and eliminating the effects of shadow. The experimental performance of our
system was tested and compared using the following schemes: Total Positive Rate
(TPR), False Negative Rate (FNR), Total Negative Rate (TNR), Error Rate (ERR)
and False Positive Rate (FPR). The performance result of the system improved on
road recognition in shadow scenario and this advancement has added tremendously
to successful navigation approaches for autonomous vehicle.


title: On strongly clean matrices over commutative clean rings

abstract:
  The literature about strongly clean matrices over commutative rings is quite
extensive. The sharpest results are about matrices over commutative local
rings, for example those by Borooah, Diesl and Dorsey. The purpose of this note
is to show that, using Pierce sheaf techniques, many of the known results about
matrices over commutative local rings can be extended to those over commutative
clean rings in general.


title: The puzzling symbiotic X-ray system 4U1700+24

abstract:
  Symbiotic X-ray binaries form a subclass of low-mass X-ray binary systems
consisting of a neutron star accreting material from a red giant donor star via
stellar wind or Roche lobe overflow. Only a few confirmed members are currently
known; 4U 1700+24 is a good candidate as it is a relatively bright X-ray
object, possibly associated with the late-type star V934 Her. We analysed the
archive {\it XMM}-Newton and Swift/XRT observations of 4U 1700+24 in order to
have a uniform high-energy ($0.3-10$ keV) view of the source. We confirmed the
existence of a red-shifted O VIII Ly-$\alpha$ transition (already observed in
the 2002 {\it XMM}-Newton data) in the high-resolution spectra collected via
the RGS instruments. The red-shift of the line is found in all the analysed
observations and, on average, it was estimated to be $\simeq 0.009$. We also
observed a modulation of the centroid energy of the line on short time scales
(a few days) and discuss the observations in the framework of different
scenarios. If the modulation is due to the gravitational red-shift of the
neutron star, it might arise from a sudden re-organization of the emitting
$X$-ray matter on the scale of a few hundreds of km. Alternatively, we are
witnessing a uni-polar jet of matter (with typical velocity of $1000-4000$ km
s$^{-1}$) possibly emitted by the neutron star in an almost face-on system. The
second possibility seems to be required by the apparent lack of any modulation
in the observed $X$-ray light curve. We also note also that the low-resolution
spectra (both {\it XMM}-Newton and Swift/XRT in the $0.3-10$ keV band) show the
existence of a black body radiation emitted by a region (possibly associated
with the neutron star polar cap) with typical size from a few tens to hundreds
of meters. The size of this spot-like region reduces as the overall luminosity
of 4U 1700+24 decreases.


title: Bayesian meta-analysis of correlation coefficients through power prior

abstract:
  To answer the call of introducing more Bayesian techniques to organizational
research (e.g., Kruschke, Aguinis, & Joo, 2012; Zyphur & Oswald, 2013), we
propose a Bayesian approach for meta-analysis with power prior in this article.
The primary purpose of this method is to allow meta-analytic researchers to
control the contribution of each individual study to an estimated overall
effect size though power prior. This is due to the consideration that not all
studies included in a meta-analysis should be viewed as equally reliable, and
that by assigning more weights to reliable studies with power prior,
researchers may obtain an overall effect size that reflects the population
effect size more accurately. We use the relationship between high-performance
work systems and financial performance as an example to illustrate how to apply
this method to organizational research. We also provide free online software
that can be used to conduct Bayesian meta-analysis proposed in this study.
Research implications and future directions are discussed.


title:
Approximation by Genuine $q$-Bernstein-Durrmeyer Polynomials in Compact
  Disks in the case $q > 1$

abstract:
  This paper deals with approximating properties of the newly defined
$q$-generalization of the genuine Bernstein-Durrmeyer polynomials in the case
$q>1$, whcih are no longer positive linear operators on $C[0,1]$. Quantitative
estimates of the convergence, the Voronovskaja type theorem and saturation of
convergence for complex genuine $q$-Bernstein-Durrmeyer polynomials attached to
analytic functions in compact disks are given. In particular, it is proved that
for functions analytic in $\left\{ z\in\mathbb{C}:\left\vert z\right\vert
<R\right\} $, $R>q,$ the rate of approximation by the genuine
$q$-Bernstein-Durrmeyer polynomials ($q>1$) is of order $q^{-n}$ versus $1/n$
for the classical genuine Bernstein-Durrmeyer polynomials. We give explicit
formulas of Voronovskaja type for the genuine $q$-Bernstein-Durrmeyer for
$q>1$.


title: A Bi-Scheduler Algorithm for Frame Aggregation in IEEE 802.11n

abstract:
  IEEE 802.11n mainly aims to provide high throughput, reliability and good
security over its other previous standards. The performance of 802.11n is very
effective on the saturated traffic through the use of frame aggregation. But
this frame aggregation will not effectively function in all scenarios. The main
objective of this paper is to improve the throughput of the wireless LAN
through effective frame aggregation using scheduler mechanism. The Bi-Scheduler
algorithm proposed in this article aims to segregate frames based on their
access categories. The outer scheduler separates delay sensitive applications
from the incoming burst of multi-part data and also decides whether to apply
Aggregated - MAC Service Data Unit (A-MSDU) aggregation technique or to send
the data without any aggregation. The inner scheduler schedules the remaining
(delay-insensitive, background and best-effort) packets using Aggregated-MAC
Protocol Data unit (A-MPDU) aggregation technique


title: Generally covariant formulation of Relative Locality in curved spacetime

abstract:
  We construct a theory of particles moving in curved both momentum space and
spacetime, being a generalization of Relative Locality. We find that in order
to construct such theory, with desired symmetries, including the general
coordinate invariance, we have to use non local position variables. It turns
out that free particles move on geodesics and momentum dependent translations
of Relative Locality are replaced with momentum dependent geodesic deviations.


title: Gesture recognition based mouse events

abstract:
  This paper presents the maneuver of mouse pointer and performs various mouse
operations such as left click, right click, double click, drag etc using
gestures recognition technique. Recognizing gestures is a complex task which
involves many aspects such as motion modeling, motion analysis, pattern
recognition and machine learning. Keeping all the essential factors in mind a
system has been created which recognizes the movement of fingers and various
patterns formed by them. Color caps have been used for fingers to distinguish
it from the background color such as skin color. Thus recognizing the gestures
various mouse events have been performed. The application has been created on
MATLAB environment with operating system as windows 7.


title: Generalized varieties of sums of powers

abstract:
  Let $X\subset\mathbb{P}^{N}$ be an irreducible, non-degenerate variety. The
generalized variety of sums of powers $VSP_H^X(h)$ of $X$ is the closure in the
Hilbert scheme $Hilb_{h}(X)$ of the locus parametrizing collections of points
$\{x_{1},...,x_{h}\}$ such that the $(h-1)$-plane $\left\langle
x_{1},...,x_{h}\right\rangle$ passes trough a fixed general point
$p\in\mathbb{P}^{N}$. When $X = V_{d}^{n}$ is a Veronese variety we recover the
classical variety of sums of powers $VSP(F,h)$ parametrizing additive
decompositions of a homogeneous polynomial as powers of linear forms. In this
paper we study the birational behavior of $VSP_H^X(h)$. In particular we will
show how some birational properties, such as rationality, unirationality and
rational connectedness, of $VSP_H^X(h)$ are inherited from the birational
geometry of variety $X$ itself.


title: Subhaloes gone Notts: Subhaloes as tracers of the dark matter halo shape

abstract:
  We study the shapes of subhalo distributions from four dark-matter-only
simulations of Milky Way type haloes. Comparing the shapes derived from the
subhalo distributions at high resolution to those of the underlying dark matter
fields we find the former to be more triaxial if theanalysis is restricted to
massive subhaloes. For three of the four analysed haloes the increased
triaxiality of the distributions of massive subhaloes can be explained by a
systematic effect caused by the low number of objects. Subhaloes of the fourth
halo show indications for anisotropic accretion via their strong triaxial
distribution and orbit alignment with respect to the dark matter field. These
results are independent of the employed subhalo finder. Comparing the shape of
the observed Milky Way satellite distribution to those of high-resolution
subhalo samples from simulations, we find an agreement for samples of bright
satellites, but significant deviations if faint satellites are included in the
analysis. These deviations might result from observational incompleteness.


title:
Calder\'on-Zygmund operators and commutators in spaces of homogeneous
  type: weighted inequalities

abstract:
  The recent proof of the sharp weighted bound for Calder\'on-Zygmund operators
has led to much investigation in sharp mixed bounds for operators and
commutators, that is, a sharp weighted bound that is a product of at least two
different $A_p$ weight constants. The reason why these are sought after is that
the product will be strictly smaller than the original one-constant bound. We
prove a variety of these bounds in spaces of homogeneous type, using the new
techniques of Lerner, for both operators and commutators.


title: Interpreting canonical tensor model in minisuperspace

abstract:
  Canonical tensor model is a theory of dynamical fuzzy spaces in arbitrary
space-time dimensions. Examining its simplest case, we find a connection to a
minisuperspace model of general relativity in arbitrary dimensions. This is a
first step in interpreting variables in canonical tensor model based on the
known language of general relativity.


title:
Suppression of X-rays from radiative shocks by their thin-shell
  instability

abstract:
  We examine X-rays from radiatively cooled shocks, focusing on how their
thin-shell instability reduces X-ray emission. For 2D simulations of collision
between equal expanding winds, we carry out a parameter study of such
instability as a function of the ratio of radiative vs. adiabatic-expansion
cooling lengths. In the adiabatic regime, the extended cooling layer suppresses
instability, leading to planar shock compression with X-ray luminosity that
follows closely the expected (Lx ~ M^2) quadratic scaling with mass-loss rate M
. In the strongly radiative limit, the X-ray emission now follows an expected
linear scaling with mass loss (Lx ~ M), but the instability deforms the shock
compression into extended shear layers with oblique shocks along fingers of
cooled, dense material. The spatial dispersion of shock thermalization limits
strong X-ray emission to the tips and troughs of the fingers, and so reduces
the X-ray emission (here by about a factor 1/50) below what is expected from
analytic radiative-shock models without unstable structure. Between these two
limits, X-ray emission can switch between a high-state associated with extended
shock compression, and a low-state characterized by extensive shear. Further
study is needed to clarify the origin of this "shear mixing reduction factor"
in X-ray emission, and its dependence on parameters like the shock Mach number.


title:
Quantifying the effects of neglecting many-body interactions in
  coarse-grained models of complex fluids

abstract:
  We describe a general simulation scheme for assessing the thermodynamic
consequences of neglecting many-body effects in coarse-grained models of
complex fluids. The method exploits the fact that the asymptote of a
simple-to-measure structural function provides direct estimates of virial
coefficients. Comparing the virial coefficients of an atomistically detailed
system with those of a coarse-grained version described by pair potentials,
permits the role of many-body effects to be quantified. The approach is applied
to two models: (i) a size-asymmetrical colloid-polymer mixture, and (ii) a
solution of star polymers. In the latter case, coarse-graining to an effective
fluid described by pair potentials is found to neglect important aspects of the
true behaviour.


title: Binary Jumbled Pattern Matching via All-Pairs Shortest Paths

abstract:
  In binary jumbled pattern matching we wish to preprocess a binary string $S$
in order to answer queries $(i,j)$ which ask for a substring of $S$ that is of
size $i$ and has exactly $j$ 1-bits. The problem naturally generalizes to
node-labeled trees and graphs by replacing "substring" with "connected
subgraph".
  In this paper, we give an ${n^2}/{2^{\Omega(\log n/\log \log n)^{1/2}}}$ time
solution for both strings and trees. This odd-looking time complexity improves
the state of the art $O(n^2/\log^2 n)$ solutions by more than any
poly-logarithmic factor. It originates from the recent seminal algorithm of
Williams for min-plus matrix multiplication. We obtain the result by giving a
black box reduction from trees to strings. This is then combined with a
reduction from strings to min-plus matrix multiplications.


title: Thermopower enhancement by encapsulating cerium in clathrate cages

abstract:
  The increasing worldwide energy consumption calls for the design of more
efficient energy systems. Thermoelectrics could be used to convert waste heat
back to useful electric energy if only more efficient materials were available.
The ideal thermoelectric material combines high electrical conductivity and
thermopower with low thermal conductivity. In this regard, the intermetallic
type-I clathrates show promise with their exceedingly low lattice thermal
conductivities [1]. Here we report the successful incorporation of cerium as
guest atom into the clathrate crystal structure. In many simpler intermetallic
compounds, this rare earth element is known to lead, via the Kondo interaction,
to strong correlation phenomena including the ocurrence of giant thermopowers
at low temperatures [2]. Indeed, we observe a 50% enhancement of the
thermopower compared to a rare earth-free reference material. Importantly, this
enhancement occurs at high temperatures and we suggest that a `rattling'
enhanced Kondo interaction [3] underlies this effect.


title: NLO QCD corrections for DVCS and TCS

abstract:
  The inclusion of QCD corrections to the Born amplitude of deeply virtual
Compton scattering in both spacelike (DVCS) and timelike (TCS) regimes modifies
the extraction process of generalized parton distributions (GPDs) from
observables. In particular, gluon contributions are by no means negligible even
in the medium energy range accessible at JLab12. We emphasize the
complementarity of spacelike and timelike measurements and raise the question
of factorization scale dependence of the O(alpha_S) results.


title:
Distribution of population averaged observables in stochastic gene
  expression

abstract:
  Observation of phenotypic diversity in a population of genetically identical
cells is often linked to the stochastic nature of chemical reactions involved
in gene regulatory networks. We investigate the distribution of population
averaged gene expression levels as a function of population, or sample, size
for several stochastic gene expression models to find out to what extent
population averaged quantities reflect the underlying mechanism of gene
expression. We consider three basic gene regulation networks corresponding to
transcription with and without gene state switching and translation. Using
analytical expressions for the probability generating function of observables
and Large Deviation Theory, we calculate the distribution and first two moments
of the population averaged mRNA and protein levels as a function of model
parameters, population size and number of measurements contained in a data set.
We validate our results using stochastic simulations also report exact results
on the asymptotic properties of population averages which show qualitative
differences among different models.


title:
Constraints from $v_2$ fluctuations for the initial state geometry of
  heavy-ion collisions

abstract:
  The ability to accurately compute the series of coefficients $v_n$
characterizing the momentum space anisotropies of particle production in
ultrarelativistic heavy ion collisions as a function of centrality is widely
regarded as a triumph of fluid dynamics as description of the bulk matter
evolution. A key ingredient to fluid dynamical modeling is however the initial
spatial distribution of matter as created by a yet not completely understood
equilibration process. A measurement directly sensitive to this initial state
geometry is therefore of high value for constraining models of pre-equilibrium
dynamics. Recently, it has been shown that such a measurement is indeed
possible in terms of the event by event probability distribution of the
normalized $v_n$ distribution as a function of centrality, which is to high
accuracy independent on the details of the subsequent fluid dynamical evolution
and hence directly reflects the primary distribution of spatial eccentricities.
We present a study of this observable using a variety of Glauber-based models
and argue that the experimental data place very tight constraints on the
initial distribution of matter and rule out all simple Glauber-based models.


title:
On Optimality Conditions for Multi-objective Problems with a Euclidean
  Cone of Preferences

abstract:
  The paper suggests a new --- to the best of the author's knowledge ---
characterization of decisions which are optimal in the multi-objective
optimization problem with respect to a definite proper preference cone, a
Euclidean cone with a prescribed angular radius. The main idea is to use the
angle distances between the unit vector and points of utility space. A
necessary and sufficient condition for the optimality in the form of an
equation is derived. The first-order necessary optimality conditions are also
obtained.


title: On the Nearest Neighbor Rule for the Metric Traveling Salesman Problem

abstract:
  We present a very simple family of traveling salesman instances with $n$
cities where the nearest neighbor rule may produce a tour that is $\Theta(\log
n)$ times longer than an optimum solution. Our family works for the graphic,
the euclidean, and the rectilinear traveling salesman problem at the same time.
It improves the so far best known lower bound in the euclidean case and proves
for the first time a lower bound in the rectilinear case.


title:
Multi-frequency linear and circular radio polarization monitoring of jet
  emission elements in $Fermi$ blazars

abstract:
  Radio emission in blazars -- the aligned subset of Active Galactic Nuclei
(AGN) -- is produced by synchrotron electrons moving relativistically in their
jet's magnetic field. Under the assumption of some degree of uniformity of the
field, the emission can be highly polarized -- linearly and circularly. In the
radio regime, the observed variability is in most of the cases attributed to
flaring events undergoing opacity evolution, i.e. transitions from optically
thick to thin emission (or vice versa). These transistions have a specific
signature in the polarization parameter space (angle and magnitude) which can
be traced with high cadence polarization monitoring and provide us with a
unique probe of the microphysics of the emitting region. Here we present the
full Stokes analysis of radio emission from blazars observed in the framework
of the F-GAMMA program and discuss the case study of PKS\,1510$-$089 which has
shown a prominent polarization event around MJD 55900.


title:
Asymptotics of determinants of Hankel matrices via non-linear difference
  equations

abstract:
  E. Heine in the 19th century studied a system of orthogonal polynomials
associated with the weight $\left[x(x-\alpha)(x-\beta)\right]^{-\frac{1}{2}}$,
$x\in[0,\alpha]$, $0<\alpha<\beta$. A related system was studied by C. J. Rees
in 1945, associated with the weight
$\left[(1-x^2)(1-k^2x^2)\right]^{-\frac{1}{2}}$, $x\in[-1,1]$, $k^2\in(0,1)$.
These are also known as elliptic orthogonal polynomials, since the moments of
the weights maybe expressed in terms of elliptic integrals. Such orthogonal
polynomials are of great interest because the corresponding Hankel determinant,
depending on a parameter $k^2$, where $0<k^2<1$ is the $\tau$~function of a
particular Painlev\'e VI, the special cases of which are related to enumerative
problems arising from string theory. We show that the recurrence coefficients,
denoted by $\beta_n(k^2),\;n=1,2,\dots$; and ${\rm p}_1(n,k^2)$, the
coefficients of $x^{n-2}$ of the monic polynomials orthogonal with respect to a
generalized version of the weight studied by Rees, $$
(1-x^2)^{\alpha}(1-k^2x^2)^{\beta},\;\;x\in[-1,1],\;\alpha>-1,\;\beta\in
\mathbb{R}, $$ satisfy second order non-linear difference equations. The large
$n$ expansion based on the difference equations when combined with known
asymptotics of the leading terms of the associated Hankel determinant yields a
complete asymptotic expansion of the Hankel determinant. The Painlev\'e
equation is also discussed as well as the generalization of the linear second
order differential equation found by Rees.


title: The equation of state and symmetry energy of low density nuclear matter

abstract:
  The symmetry energy of nuclear matter is a fundamental ingredient in the
investigation of exotic nuclei, heavy-ion collisions and astrophysical
phenomena. A recently developed quantum statistical (QS) approach that takes
the formation of clusters into account predicts low density symmetry energies
far above the usually quoted mean field limits. A consistent description of the
symmetry energy has been developed that joins the correct low-density limit
with values calculated from quasi-particle approaches valid near the saturation
density. The results are confronted with experimental values for free symmetry
energies and internal symmetry energies, determined at sub-saturation densities
and temperatures below 10 MeV using data from heavy-ion collisions. There is
very good agreement between the experimental symmetry energy values and those
calculated in the QS approach


title:
Removing beam asymmetry bias in precision CMB temperature and
  polarisation experiments

abstract:
  Asymmetric beams can create significant bias in estimates of the power
spectra from CMB experiments. With the temperature power spectrum many orders
of magnitude stronger than the B-mode power spectrum any systematic error that
couples the two must be carefully controlled and/or removed. Here, we derive
unbiased estimators for the CMB temperature and polarisation power spectra
taking into account general beams and general scan strategies. A simple
consequence of asymmetric beams is that, even with an ideal scan strategy where
every sky pixel is seen at every orientation, there will be residual coupling
from temperature power to B-mode power if the orientation of the beam asymmetry
is not aligned with the orientation of the co-polarisation. We test our
correction algorithm on simulations of two temperature-only experiments and
demonstrate that it is unbiased. The simulated experiments use realistic scan
strategies, noise levels and highly asymmetric beams. We also develop a
map-making algorithm that is capable of removing beam asymmetry bias at the map
level. We demonstrate its implementation using simulations and show that it is
capable of accurately correcting both temperature and polarisation maps for all
of the effects of beam asymmetry including the effects of temperature to
polarisation leakage.


title:
Prediction of a $Z_c(4000)$ $D^* \bar D^*$ state and relationship to the
  claimed $Z_c(4025)$

abstract:
  After discussing the OZI suppression of one light meson exchange in the
interaction of $D^* \bar D^*$ with isospin I=1, we study the contribution of
two pion exchange to the interaction and the exchange of a heavy vector
$J/\psi$. We find this latter mechanism weak but enough to barely bind the
system in J=2 with a mass around 4000 MeV, while the effect of the two pion
exchange is a net attraction but weaker than that from $J/\psi$ exchange. We
discuss this state and try to relate it to the $Z_c(4025)$ state, above the
$D^* \bar D^*$ threshold, claimed in an experiment at BES from and enhancement
of the $D^* \bar D^*$ distribution close to threshold. Together with the
results from a recent reanalysis of the BES experiment showing that it is
compatible with a J=2 state below threshold around 3990 MeV, we conclude that
the BES experiment could be showing the existence of the state that we find in
our approach.


title:
8D Likelihood Effective Higgs Couplings Extraction Framework in the
  Golden Channel

abstract:
  In this paper we build a comprehensive analysis framework to perform direct
extraction of all possible effective Higgs couplings to neutral electroweak
gauge bosons in the decay to electrons and muons, the so called `golden
channel'. Our framework is based on a maximum likelihood method constructed
from analytic expressions of the fully differential cross sections for $h
\rightarrow 4\ell$ and for the dominant irreducible $q\bar{q} \rightarrow
4\ell$ background, where $4\ell = 2e2\mu, 4e, 4\mu$. Detector effects are
included by an explicit convolution of these analytic expressions with the
appropriate transfer function over all center of mass variables. Using the full
set of decay observables, we construct an unbinned 8-dimensional detector-level
likelihood function which is continuous in the effective couplings and includes
systematic uncertainties. We consider all possible $ZZ$, $Z\gamma$ and
$\gamma\gamma$ couplings, allowing for general CP odd/even admixtures and any
possible phases. We describe how the convolution is performed and demonstrate
the validity and power of the framework with a number of supporting checks and
example fits. The framework can be used to perform a variety of multi-parameter
extractions, including their correlations, to determine the Higgs couplings to
neutral electroweak gauge bosons using data obtained at the LHC and other
future colliders.


title: Correlations of magnetic features and the torsional pattern

abstract:
  The striking similarity between the cyclic equatorward migration of the
torsional oscillation belts and the sunspot activity latitudes inspired several
attempts to seek an explanation of the torsional phenomenon in terms of
interactions between flux ropes and plasma motions. The aim of the present work
is to examine the spatial and temporal coincidences of the torsional waves and
the emergence of sunspot magnetic fields. The locations of the shearing
latitudes have been compared with the distributions of certain sunspot
parameters by using sunspot data of more than two cycles. The bulges of the
sunspot number and area distributions tend to be loacted within the 'forward'
belts close to their poleward shearing borders. A possible geometry of the
magnetic and velocity field interacion is proposed.


title:
Evidence for $\nu_\mu \to \nu_\tau$ appearance in the CNGS neutrino beam
  with the OPERA experiment

abstract:
  The OPERA experiment is designed to search for $\nu_{\mu} \rightarrow
\nu_{\tau}$ oscillations in appearance mode i.e. through the direct observation
of the $\tau$ lepton in $\nu_{\tau}$ charged current interactions. The
experiment has taken data for five years, since 2008, with the CERN Neutrino to
Gran Sasso beam. Previously, two $\nu_{\tau}$ candidates with a $\tau$ decaying
into hadrons were observed in a sub-sample of data of the 2008-2011 runs. Here
we report the observation of a third $\nu_\tau$ candidate in the
$\tau^-\to\mu^-$ decay channel coming from the analysis of a sub-sample of the
2012 run. Taking into account the estimated background, the absence of
$\nu_{\mu} \rightarrow \nu_{\tau}$ oscillations is excluded at the 3.4 $\sigma$
level.


title:
Clustering, fronts, and heat transfer in turbulent suspensions of heavy
  particles

abstract:
  Heavy inertial particles transported by a turbulent flow are shown to
concentrate in the regions where an advected passive scalar, such as
temperature, displays very strong front-like discontinuities. This novel effect
is responsible for extremely high levels of fluctuations for the passive field
sampled by the particles that impacts the heat fluxes exchanged between the
particles and the surrounding fluid. Instantaneous and averaged heat fluxes are
shown to follow strongly intermittent statistics and anomalous scaling laws.


title:
Mediation analysis with missing data through multiple imputation and
  bootstrap

abstract:
  A method using multiple imputation and bootstrap for dealing with missing
data in mediation analysis is introduced and implemented in SAS. Through
simulation studies, it is shown that the method performs well for both MCAR and
MAR data without and with auxiliary variables. It is also shown that the method
works equally well for MNAR data if auxiliary variables related to missingness
are included. The application of the method is demonstrated through the
analysis of a subset of data from the National Longitudinal Survey of Youth.


title:
Adler-Gelfand-Dickey approach to classical W-algebras within the theory
  of Poisson vertex algebras

abstract:
  We put the Adler-Gelfand-Dickey approach to classical W-algebras in the
framework of Poisson vertex algebras. We show how to recover the bi-Poisson
structure of the KP hierarchy, together with its generalizations and reduction
to the N-th KdV hierarchy, using the formal distribution calculus and the
lambda-bracket formalism. We apply the Lenard-Magri scheme to prove
integrability of the corresponding hierarchies. We also give a simple proof of
a theorem of Kupershmidt and Wilson in this framework. Based on this approach,
we generalize all these results to the matrix case. In particular, we find
(non-local) bi-Poisson structures of the matrix KP and the matrix N-th KdV
hierarchies, and we prove integrability of the N-th matrix KdV hierarchy.


title:
i-TED: A novel concept for high-sensitivity (n,$\gamma$) cross section
  measurements

abstract:
  A new method for measuring \ngr cross sections aiming at enhanced
signal-to-background ratio is presented. This new approach is based on the
combination of the pulse-height weighting technique with a total energy
detection system that features $\gamma$-ray imaging capability (i-TED). The
latter allows one to exploit Compton imaging techniques to discriminate between
true capture $\gamma$-rays arising from the sample under study and background
$\gamma$-rays coming from contaminant neutron (prompt or delayed) captures in
the surrounding environment. A general proof-of-concept detection system for
this application is presented in this article together with a description of
the imaging method and a conceptual demonstration based on Monte Carlo
simulations.


title:
Casimir effect due to a slowly rotating source in the weak field
  approximation

abstract:
  We calculate the renormalized vacuum energy density for a massless scalar
field confined between two nearby parallel plates formed by ideal uncharged
conductors, placed very close to the surface of a rotating spherical
gravitational source with mass $M$, radius $R$ and momentum angular $J$, at the
equatorial region. We consider that the source rotates slowly and that the
gravitational field is weak. Corrections to the Casimir energy density induced
by the gravitational field generated by this source are calculated up to
$M/R^2$ order. The obtained results show us that there is an important
modification in the Casimir energy only in this order of approximation, which
depends on the surface gravity as well as on the rotation of the source.
Thermal corrections to the Casimir energy found also are calculated in all
these orders.


title:
Unofficial history of a joint work with Dieter Happel and of two
  unexpected quotations

abstract:
  This survey contains a recollection of results, problems and conversations
which go back to the early years of Representation Theory and Tilting Theory.


title:
Actor-Critic Algorithms for Learning Nash Equilibria in N-player
  General-Sum Games

abstract:
  We consider the problem of finding stationary Nash equilibria (NE) in a
finite discounted general-sum stochastic game. We first generalize a non-linear
optimization problem from Filar and Vrieze [2004] to a $N$-player setting and
break down this problem into simpler sub-problems that ensure there is no
Bellman error for a given state and an agent. We then provide a
characterization of solution points of these sub-problems that correspond to
Nash equilibria of the underlying game and for this purpose, we derive a set of
necessary and sufficient SG-SP (Stochastic Game - Sub-Problem) conditions.
Using these conditions, we develop two actor-critic algorithms: OFF-SGSP
(model-based) and ON-SGSP (model-free). Both algorithms use a critic that
estimates the value function for a fixed policy and an actor that performs
descent in the policy space using a descent direction that avoids local minima.
We establish that both algorithms converge, in self-play, to the equilibria of
a certain ordinary differential equation (ODE), whose stable limit points
coincide with stationary NE of the underlying general-sum stochastic game. On a
single state non-generic game (see Hart and Mas-Colell [2005]) as well as on a
synthetic two-player game setup with $810,000$ states, we establish that
ON-SGSP consistently outperforms NashQ ([Hu and Wellman, 2003] and FFQ
[Littman, 2001] algorithms.


title:
The XXL Survey V: Detection of the Sunyaev-Zel'dovich effect of the
  Redshift 1.9 Galaxy Cluster XLSSU J021744.1-034536 with CARMA

abstract:
  We report the detection of the Sunyaev-Zel'dovich (SZ) effect of galaxy
cluster XLSSU J021744.1-034536, using 30 GHz CARMA data. This cluster was
discovered via its extended X-ray emission in the XMM-Newton Large Scale
Structure survey, the precursor to the XXL survey. It has a photometrically
determined redshift $z=1.91^{+0.19}_{-0.21}$, making it among the most distant
clusters known, and nominally the most distant for which the SZ effect has been
measured. The spherically integrated Comptonization is
$Y_{500}=(3.0\pm0.4)\times 10^{-12}$, a measurement which is relatively
insensitive to assumptions regarding the size and redshift of the cluster, as
well as the background cosmology. Using a variety of locally calibrated cluster
scaling relations extrapolated to z~2, we estimate a mass $M_{500} \sim
(1$-$2)\times 10^{14}M_{sun}$ from the X-ray flux and SZ signal. The measured
properties of this cluster are in good agreement with the extrapolation of an
X-ray luminosity-SZ effect scaling relation calibrated from clusters discovered
by the South Pole Telescope at higher masses and lower redshifts. The full
XXL-CARMA sample will provide a more complete, multi-wavelength census of
distant clusters in order to robustly extend the calibration of cluster scaling
relations to these high redshifts.


title: Axial resonances a1(1260), b1(1235) and their decays from the lattice

abstract:
  The light axial-vector resonances $a_1(1260)$ and $b_1(1235)$ are explored in
Nf=2 lattice QCD by simulating the corresponding scattering channels $\rho\pi$
and $\omega\pi$. Interpolating fields $\bar{q} q$ and $\rho\pi$ or $\omega\pi$
are used to extract the s-wave phase shifts for the first time. The $\rho$ and
$\omega$ are treated as stable and we argue that this is justified in the
considered energy range and for our parameters $m_\pi\simeq 266~$MeV and
$L\simeq 2~$fm. We neglect other channels that would be open when using
physical masses in continuum. Assuming a resonance interpretation a
Breit-Wigner fit to the phase shift gives the $a_1(1260)$ resonance mass
$m_{a1}^{res}=1.435(53)(^{+0}_{-109})$ GeV compared to $m_{a1}^{exp}=1.230(40)$
GeV. The $a_1$ width $\Gamma_{a1}(s)=g^2 p/s$ is parametrized in terms of the
coupling and we obtain $g_{a_1\rho\pi}=1.71(39)$ GeV compared to
$g_{a_1\rho\pi}^{exp}=1.35(30)$ GeV derived from $\Gamma_{a1}^{exp}=425(175)$
MeV. In the $b_1$ channel, we find energy levels related to $\pi(0)\omega(0)$
and $b_1(1235)$, and the lowest level is found at $E_1 \gtrsim m_\omega+m_\pi$
but is within uncertainty also compatible with an attractive interaction.
Assuming the coupling $g_{b_1\omega\pi}$ extracted from the experimental width
we estimate $m_{b_1}^{res}=1.414(36)(^{+0}_{-83})$.


title:
Understanding the dynamical structure of pulsating stars. HARPS
  spectroscopy of the delta Scuti stars rho Pup and DX Cet

abstract:
  High-resolution spectroscopy is a powerful tool to study the dynamical
structure of pulsating stars atmosphere. We aim at comparing the line asymmetry
and velocity of the two delta Sct stars rho Pup and DX Cet with previous
spectroscopic data obtained on classical Cepheids and beta Cep stars. We
obtained, analysed and discuss HARPS high-resolution spectra of rho Pup and DX
Cet. We derived the same physical quantities as used in previous studies, which
are the first-moment radial velocities and the bi-Gaussian spectral line
asymmetries. The identification of f=7.098 (1/d) as a fundamental radial mode
and the very accurate Hipparcos parallax promote rho Pup as the best standard
candle to test the period-luminosity relations of delta Sct stars. The action
of small-amplitude nonradial modes can be seen as well-defined cycle-to-cycle
variations in the radial velocity measurements of rho Pup. Using the
spectral-line asymmetry method, we also found the centre-of-mass velocities of
rho Pup and DX Cet, V_gamma = 47.49 +/- 0.07 km/s and V_gamma = 25.75 +/- 0.06
km/s, respectively. By comparing our results with previous HARPS observations
of classical Cepheids and beta Cep stars, we confirm the linear relation
between the atmospheric velocity gradient and the amplitude of the radial
velocity curve, but only for amplitudes larger than 22.5 km/s. For lower values
of the velocity amplitude (i.e., < 22.5 km/s), our data on rho Pup seem to
indicate that the velocity gradient is null, but this result needs to be
confirmed with additional data. We derived the Baade-Wesselink projection
factor p = 1.36 +/- 0.02 for rho Pup and p = 1.39 +/- 0.02 for DX Cet. We
successfully extended the period-projection factor relation from classical
Cepheids to delta Scuti stars.


title: Particle Statistics, Frustration, and Ground-State Energy

abstract:
  We study the connections among particle statistics, frustration, and
ground-state energy in quantum many-particle systems. In the absence of
interaction, the influence of particle statistics on the ground-state energy is
trivial: the ground-state energy of noninteracting bosons is lower than that of
free fermions because of Bose-Einstein condensation and Pauli exclusion
principle. In the presence of hard-core or other interaction, however, the
comparison is not trivial. Nevertheless, the ground-state energy of hard-core
bosons is proved to be lower than that of spinless fermions, if all the hopping
amplitudes are nonnegative. The condition can be understood as the absence of
frustration among hoppings. By mapping the many-body Hamiltonian to a
tight-binding model on a fictitious lattice, we show that the Fermi statistics
of the original particles introduces an effective magnetic flux in the
fictitious lattice. The latter can be regarded as a frustration, since it leads
to a destructive interference among different paths along which a single
particle is propagating. If we introduce hopping frustration, the hopping
frustration is expected to compete with "effective frustration", leading to the
possibility that the ground-state energy of hard-core bosons can be higher than
that of fermions. We present several examples, in which the ground-state energy
of hard-core bosons is proved to be higher than that of fermions due to the
hopping frustration. The basic ideas were reported in a recent Letter [W.-X.
Nie, H. Katsura, and M. Oshikawa, Phys. Rev. Lett. 111, 100402 (2013)]; more
details and several extensions, including one to the spinful case, are
discussed in the present paper.


title: Harmonic Analysis associated with a discrete Laplacian

abstract:
  It is well-known that the fundamental solution of $$ u_t(n,t)=
u(n+1,t)-2u(n,t)+u(n-1,t), \quad n\in\mathbb{Z}, $$ with $u(n,0) =\delta_{nm}$
for every fixed $m \in\mathbb{Z}$, is given by $u(n,t) = e^{-2t}I_{n-m}(2t)$,
where $I_k(t)$ is the Bessel function of imaginary argument. In other words,
the heat semigroup of the discrete Laplacian is described by the formal series
$$ W_tf(n) = \sum_{m\in\mathbb{Z}} e^{-2t} I_{n-m}(2t) f(m). $$ By using
semigroup theory, this formula allows us to analyze some operators associated
with the discrete Laplacian. In particular, we obtain the maximum principle for
the discrete fractional Laplacian, weighted $\ell^p(\mathbb{Z})$-boundedness of
conjugate harmonic functions, Riesz transforms and square functions of
Littlewood-Paley.
  Interestingly, it is shown that the Riesz transforms coincide essentially
with the so called discrete Hilbert transform defined by D. Hilbert at the
beginning of the XX century. We also see that these Riesz transforms are limits
of the conjugate harmonic functions.
  The results rely on a careful use of several properties of Bessel functions.


title: On the Domination Polynomials of Friendship Graphs

abstract:
  Let $G$ be a simple graph of order $n$. The {\em domination polynomial} of
$G$ is the polynomial ${D(G, x)=\sum_{i=0}^{n} d(G,i) x^{i}}$, where $d(G,i)$
is the number of dominating sets of $G$ of size $i$.
  Let $n$ be any positive integer and $F_n$ be the Friendship graph with $2n +
1$ vertices and $3n$ edges, formed by the join of $K_{1}$ with $nK_{2}$. We
study the domination polynomials of this family of graphs, and in particular
examine the domination roots of the family, and find the limiting curve for the
roots. We also show that for every $n\geq 2$, $F_n$ is not
$\mathcal{D}$-unique, that is, there is another non-isomorphic graph with the
same domination polynomial. Also we construct some families of graphs whose
real domination roots are only $-2$ and $0$. Finally, we conclude by discussing
the domination polynomials of a related family of graphs, the $n$-book graphs
$B_n$, formed by joining $n$ copies of the cycle graph $C_4$ with a common
edge.


title: Instantons and odd Khovanov homology

abstract:
  We construct a spectral sequence from the reduced odd Khovanov homology of a
link converging to the framed instanton homology of the double cover branched
over the link, with orientation reversed. Framed instanton homology counts
certain instantons on the cylinder of a 3-manifold connect-summed with a
3-torus. En route, we provide a new proof of Floer's surgery exact triangle for
instanton homology using metric stretching maps, and generalize the exact
triangle to a link surgeries spectral sequence. Finally, we relate framed
instanton homology to Floer's instanton homology for admissible bundles.


title:
Approaching the Trap-Free Limit in Organic Single Crystal Field-Effect
  Transistors

abstract:
  Crystalline organic semiconductors, bonded by weak van der Waals forces,
exhibit macroscopic properties that are very similar to those of inorganic
semiconductors. While there are many open questions concerning the microscopic
nature of charge transport, minimizing the density of trap states (trap DOS) is
crucial to elucidate the intrinsic transport mechanism.
  We explore the limits of state-of-the-art organic crystals by measuring
single crystalline rubrene field-effect transistors that show textbook like
transfer characteristics, indicating a very low trap DOS. Particularly, the
high purity of the crystals and the very clean interface to the gate dielectric
are reflected in an unprecedentedly low subthreshold swing of 65 ${\rm mV /
decade}$, remarkably close to the fundamental limit of $58.5 {\rm mV /
decade}$.
  From the measured subthreshold behavior we have consistently quantified the
trap DOS by two different methods, yielding an exceedingly low trap density of
$D_{bulk} = 1 \times 10^{13}~{\rm cm^{-3}eV^{-1}}$ at an energy of
$\sim0.62~{\rm eV}$. These numbers correspond to one trap per eV in $10^8$
rubrene molecules. The equivalent density of traps located at the interface is
$D_{it} = 3 \times 10^{9}~{\rm cm^{-2}eV^{-1}}$ which puts them on par with the
best crystalline ${\rm SiO_2/Si}$ field-effect transistors.


title:
Coaxing Cosmic 21cm Fluctuations from the Polarized Sky using m-mode
  Analysis

abstract:
  In this paper we continue to develop the m-mode formalism, a technique for
efficient and optimal analysis of wide-field transit radio telescopes, targeted
at 21 cm cosmology. We extend this formalism to give an accurate treatment of
the polarised sky, fully accounting for the effects of polarisation leakage and
cross-polarisation. We use the geometry of the measured set of visibilities to
project down to pure temperature modes on the sky, serving as a significant
compression, and an effective first filter of polarised contaminants. We use
the m-mode formalism with the Karhunen-Loeve transform to give a highly
efficient method for foreground cleaning, and demonstrate its success in
cleaning realistic polarised skies observed with an instrument suffering from
substantial off axis polarisation leakage. We develop an optimal quadratic
estimator in the m-mode formalism, which can be efficiently calculated using a
Monte-Carlo technique. This is used to assess the implications of foreground
removal for power spectrum constraints where we find that our method can clean
foregrounds well below the foreground wedge, rendering only scales $k_\parallel
< 0.02 h \,\mathrm{Mpc}^{-1}$ inaccessible. As this approach assumes perfect
knowledge of the telescope, we perform a conservative test of how essential
this is by simulating and analysing datasets with deviations about our assumed
telescope. Assuming no other techniques to mitigate bias are applied, we
recover unbiased power spectra when the per-feed beam width to be measured to
0.1%, and amplifier gains to be known to 1% within each minute. Finally, as an
example application, we extend our forecasts to a wideband 400-800 MHz
cosmological observation and consider the implications for probing dark energy,
finding a medium-sized cylinder telescope improves the DETF Figure of Merit by
around 70% over Planck and Stage II experiments alone.


title:
Closed equations of the two-point functions for tensorial group field
  theory

abstract:
  In this paper we provide the closed equations that satisfy two-point
correlation functions of the rank 3 and 4 tensorial group field theory. The
formulation of the present problem extends the method used by Grosse and
Wulkenhaar in [arXiv 0909.1389] to the tensor case. Ward-Takahashi identities
and Schwinger-Dyson equations are combined to establish a nonlinear integral
equation for the two-point functions. In the 3D case the solution of this
equation is given perturbatively at second order of the coupling constant.


title:
Order, Chaos and Quasi Symmetries in a First-Order Quantum Phase
  Transition

abstract:
  We study the competing order and chaos in a first-order quantum phase
transition with a high barrier. The boson model Hamiltonian employed,
interpolates between its U(5) (spherical) and SU(3) (deformed) limits. A
classical analysis reveals regular (chaotic) dynamics at low (higher) energy in
the spherical region, coexisting with a robustly regular dynamics in the
deformed region. A quantum analysis discloses, amidst a complicated
environment, persisting regular multiplets of states associated with partial
U(5) and quasi SU(3) dynamical symmetries.


title:
Triplet absorption spectroscopy and electromagnetically induced
  transparency

abstract:
  Coherence phenomena in four-level atomic system, cyclicly driven by three
coherent fields, are investigated thoroughly at zero and weak magnetic fields.
Each strongly interacting atomic state is converted to a triplet due to a
dynamical Stark effect. Two dark lines with a Fano-like profile are arising in
the triplet absorption spectrum with anomalous dispersions. We provide the
conditions to control the widths of the transparency windows by means of the
relative phase of the driving fields and the intensity of the microwave field,
that closes the optical system loop. The effect of the Doppler broadening on
results of the triplet absorption spectroscopy is analysed in detail.


title:
Mechanical behavior of steels: from fundamental mechanisms to
  macroscopic deformation

abstract:
  My scientific activities aim at understand and predict the mechanical
behaviour of steels, from fundamental mechanisms to macroscopic deformation.
This manuscript is dedicated to the TWIP effect (TWinning Induced Plasticity)
of high manganese austenitic steels and DP effect (Dual-Phase) in more
conventional Ferrite-Martensite steels.


title: Shear banding of colloidal glasses - a dynamic first order transition?

abstract:
  We demonstrate that application of an increasing shear field on a glass leads
to an intriguing dynamic first order transition in analogy to equilibrium
transitions. By following the particle dynamics as a function of the driving
field in a colloidal glass, we identify a critical shear rate upon which the
diffusion time scale of the glass exhibits a sudden discontinuity. Using a new
dynamic order parameter, we show that this discontinuity is analogous to a
first order transition, in which the applied stress acts as the conjugate field
on the system's dynamic evolution. These results offer new perspectives to
comprehend the generic shear banding instability of a wide range of amorphous
materials.


title: NoSQL Databases

abstract:
  In this document, I present the main notions of NoSQL databases and compare
four selected products (Riak, MongoDB, Cassandra, Neo4J) according to their
capabilities with respect to consistency, availability, and partition
tolerance, as well as performance. I also propose a few criteria for selecting
the right tool for the right situation.


title: On Forbidden Submatrices

abstract:
  Given a $k\times l$ $(0,1)$-matrix $F$, we denote by $\mathrm{fs}(m,F)$ the
largest number for which there is an $m \times \mathrm{fs}(m,F)$ $(0,1)$-matrix
with no repeated columns and no induced submatrix equal to $F$. A conjecture of
Anstee, Frankl, F\"{u}redi and Pach states that $\mathrm{fs}(m,F) = O(m^k)$ for
a fixed matrix $F$. The main results of this paper are that $\mathrm{fs}(m,F) =
m^{2+ o(1)}$ if $k=2$ and that $\mathrm{fs}(m,F) = m^{5k/3 -1 + o(1)}$ if
$k\geq 3$.


title:
Restricted Equilibrium and the Energy Cascade in Rotating and Stratified
  Flows

abstract:
  Most of the turbulent flows appearing in nature (e.g. geophysical and
astrophysical flows) are subjected to strong rotation and stratification. These
effects break the symmetries of classical, homogenous isotropic turbulence. In
doing so, they introduce a natural decomposition of phase space in terms of
wave modes and potential vorticity modes. The appearance of a new time scale
associated to the propagation of waves, in addition to the eddy turnover time,
increases the complexity of the energy transfers between the various scales;
nonlinearly interacting waves may dominate at some scales while balanced motion
may prevail at others. In the end, it is difficult to predict \emph{a priori}
if the energy cascades downscale as in homogeneous isotropic turbulence,
upscale as expected from balanced dynamics, or follows yet another
phenomenology.
  In this paper, we suggest a theoretical approach based on equilibrium
statistical mechanics for the ideal system, inspired from the restricted
partition function formalism introduced in metastability studies. In this
framework, we show analytically that in the presence of rotation, when the
dynamics is restricted to the slow modes, the equilibrium energy spectrum
features an infrared divergence characteristic of an inverse cascade regime,
whereas this is not the case for purely stratified flows.


title: A universal bound on the variations of bounded convex functions

abstract:
  Given a convex set $C$ in a real vector space $E$ and two points $x,y\in C$,
we investivate which are the possible values for the variation $f(y)-f(x)$,
where $f:C\longrightarrow [m,M]$ is a bounded convex function. We then rewrite
the bounds in terms of the Funk weak metric, which will imply that a bounded
convex function is Lipschitz-continuous with respect to the Thompson and
Hilbert metrics. The bounds are also proved to be optimal. We also exhibit the
maximal subdifferential of a bounded convex function at a given point $x\in C$.


title: North-south differences of solar cycles

abstract:
  A long-term variation is detected in the north-south differences of the solar
activity, the phase difference of hemispheric cycles alternates by four Schwabe
cycles. This variability is demonstrated by two different methods. It can be
the related to the Gleissberg cycle. The variation of the sunspot group tilts
is similar to the hemispheric phase lags on a shorter timescale. Some possible
relations are mentioned.


title: Particle response during the yielding transition of colloidal glasses

abstract:
  Yielding is central to the relaxation, flow and fracture of a wide range of
soft and molecular glasses, but its microscopic origin remains unclear. Here,
we elucidate the yielding of a colloidal glass by using x-ray scattering to
monitor the structure factor during the yielding process. We apply a recently
introduced combination of small-angle x-ray scattering and rheology to the
oscillatory shear, and follow the structure factor during the increasing strain
amplitude. Surprisingly, we observe a sharp transition in the orientational
ordering of the nearest-neighbor structure upon yielding, in contrast to the
smooth variation of the viscoelastic moduli. This transition is accompanied by
a sudden change of intensity fluctuations towards Gaussian distributions. We
thus identify yielding as a new, dynamically induced transition of the glass in
response to the applied shear.


title: Minimizing the Time of Detection of Large (Probably) Prime Numbers

abstract:
  In this paper we present the experimental results that more clearly than any
theory suggest an answer to the question: when in detection of large (probably)
prime numbers to apply, a very resource demanding, Miller-Rabin algorithm. Or,
to put it another way, when the dividing by first several tens of prime numbers
should be replaced by primality testing? As an innovation, the procedure above
will be supplemented by considering the use of the well-known Goldbach's
conjecture in the solving of this and some other important questions about the
RSA cryptosystem, always guided by the motto "do not harm" - neither the
security nor the time spent.


title:
Observation of Time-Reversal Symmetry Breaking in the
  Non-Centrosymmetric Superconductor Re6Zr

abstract:
  We have investigated the superconducting state of the non-centrosymmetric
compound Re6Zr using magnetization, heat capacity, and muon-spin
relaxation/rotation (muSR) measurements. Re6Zr has a superconducting transition
temperature, Tc = 6.75 K. Transverse-field muSR experiments, used to probe the
superfluid density, suggest an s-wave character for the superconducting gap.
However, zero and longitudinal-field muSR data reveal the presence of
spontaneous static magnetic fields below Tc indicating that time-reversal
symmetry is broken in the superconducting state and an unconventional pairing
mechanism. An analysis of the pairing symmetries identifies the ground states
compatible with time-reversal symmetry breaking.


title: SPIRE Map-Making Test Report

abstract:
  The photometer section of SPIRE is one of the key instruments on board of
Herschel. Its legacy depends very much on how well the scanmap observations
that it carried out during the Herschel mission can be converted to high
quality maps. In order to have a comprehensive assessment on the current status
of SPIRE map-making, as well as to provide guidance for future development of
the SPIRE scan-map data reduction pipeline, we carried out a test campaign on
SPIRE map-making. In this report, we present results of the tests in this
campaign.


title: Local unitary symmetries and entanglement invariants

abstract:
  We investigate the relation between local unitary symmetries and entanglement
invariants of multi-qubit systems. The Hilbert space of such systems can be
stratified in terms of states with different types of symmetry. We review the
connection between this stratification and the ring of entanglement invariants
and the corresponding geometric description in terms of algebraic varieties. On
a stratum of a non-trivial symmetry group the invariants of the symmetry
preserving operations gives a sufficient description of entanglement. Finding
these invariants is often a simpler problem than finding the invariants of the
local unitary group. The conditions, as given by the Luna-Richardson theorem,
for when the ring of such invariants is isomorphic to the ring of local unitary
invariants on the stratum are discussed. As an example we consider symmetry
groups that can be diagonalized by local unitary operations and for which the
group action on each qubit is non-trivial. On the stratum of such a symmetry
the entanglement can be described in terms of a canonical form and the
invariants of the symmetry preserving operations. This canonical form and the
invariants are directly determined by the symmetry group. Further, we briefly
discuss how some recently proposed entanglement classification schemes capture
symmetry properties.


title: The Kakimizu complex of a surface

abstract:
  The Kakimizu complex is usually defined in the context of knots, where it is
known to be quasi-Euclidean. We here generalize the definition of the Kakimizu
complex to surfaces and 3-manifolds (with or without boundary). Interestingly,
in the setting of surfaces, the complexes and the techniques turn out to
replicate those used to study the Torelli group, {\it i.e.,} the "nonlinear"
subgroup of the mapping class group. Our main results are that the Kakimizu
complexes of a surface are contractible and that they need not be
quasi-Euclidean. It follows that there exist (product) $3$-manifolds whose
Kakimizu complexes are not quasi-Euclidean.


title: On the Hyperbolizing metric spaces

abstract:
  In this paper, we prove that the metric space $(Z\setminus M,u_Z)$ defined by
Z.Ibragimov is asymptotically $PT_{-1}$ if the metric space $(Z,d)$ is
$PT_{0}$, where $M$ is a nonempty closed proper subset of $Z$. Secondly, based
on the metric $u_Z$, we define a new kind of metric $k_{z}$ on the set
$Z\setminus M$ and show that the new metric space $(Z\setminus M,k_{Z})$ is
also asymptotically $PT_{-1}$ without the assumption of $PT_{0}$ on the metric
space $(Z,d)$.


title:
Latent Sentiment Detection in Online Social Networks: A
  Communications-oriented View

abstract:
  In this paper, we consider the problem of latent sentiment detection in
Online Social Networks such as Twitter. We demonstrate the benefits of using
the underlying social network as an Ising prior to perform network aided
sentiment detection. We show that the use of the underlying network results in
substantially lower detection error rates compared to strictly features-based
detection. In doing so, we introduce a novel communications-oriented framework
for characterizing the probability of error, based on information-theoretic
analysis. We study the variation of the calculated error exponent for several
stylized network topologies such as the complete network, the star network and
the closed-chain network, and show the importance of the network structure in
determining detection performance.


title:
The beta decay of 38Ca: Sensitive test of isospin symmetry-breaking
  corrections from mirror superallowed 0+-to-0+ transitions

abstract:
  We report the first branching-ratio measurement of the superallowed 0+-to-0+
beta transition from 38Ca. The result, 0.7728(16), leads to an ft value of
3062.3(68)s with a relative precision of +/-0.2%. This makes possible a
high-precision comparison of the ft values for the mirror superallowed
transitions, 38Ca-to-38mK and 38mK-to-38Ar, which sensitively tests the isospin
symmetry-breaking corrections required to extract Vud, the up-down quark-mixing
element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, from superallowed beta
decay. The result supports the corrections currently used, and points the way
to even tighter constraints on CKM unitarity.


title:
Mathematical Properties of a Class of Four-dimensional Neutral Signature
  Metrics

abstract:
  While the Lorenzian and Riemanian metrics for which all polynomial scalar
curvature invariants vanish (the VSI property) are well-studied, less is known
about the four-dimensional neutral signature metrics with the VSI property.
Recently it was shown that the neutral signature metrics belong to two distinct
subclasses: the Walker and Kundt metrics. In this paper we have chosen an
example from each of the two subcases of the Ricci-flat VSI Walker metrics
respectively.
  To investigate the difference between the metrics we determine the existence
of a null, geodesic, expansion-free, shear-free and vorticity-free vector, and
classify these spaces using their infinitesimal holonomy algebras. The
geometric implications of the holonomy algebras are further studied by
identifying the recurrent or covariantly constant null vectors, whose existence
is required by the holonomy structure in each example. We conclude the paper
with a simple example of the equivalence algorithm for these pseudo-Riemannian
manifolds, which is the only approach to classification that provides all
necessary information to determine equivalence.


title: 2+1 flavour thermal studies on an anisotropic lattice

abstract:
  The FASTSUM collaboration has initiated a detailed study of thermal QCD using
2+1 flavours of improved Wilson quarks on anisotropic lattices. Spatial volumes
of (3fm)^3 and (4fm)^3 are used at fixed cut-off with temperatures ranging from
40 to 350 MeV (corresponding to temporal lattice extents of 128 to 16 lattice
units). Results presented here include the deconfinement temperature and a
study of the restoration of chiral symmetry, together with a brief summary of
our collaboration's other results from these ensembles.


title:
Extragalactic gamma-ray signal from dark matter annihilation: an
  appraisal

abstract:
  We re-evaluate the extragalactic gamma-ray flux prediction from dark matter
annihilation in the approach of integrating over the nonlinear matter power
spectrum, extrapolated to the free-streaming scale. We provide an estimate of
the uncertainty based entirely on available N-body simulation results and
minimal theoretical assumptions. We illustrate how an improvement in the
simulation resolution, exemplified by the comparison between the Millennium and
Millennium II simulations, affects our estimate of the flux uncertainty and we
provide a "best guess" value for the flux multiplier, based on the assumption
of stable clustering for the dark matter perturbations described as a
collision-less fluid. We achieve results comparable to traditional Halo Model
calculations, but with a much simpler procedure and a more general approach, as
it relies only on one, directly measurable quantity. In addition we discuss the
extension of our calculation to include baryonic effects as modeled in
hydrodynamical cosmological simulations and other possible sources of
uncertainty that would in turn affect indirect dark matter signals. Upper limit
on the integrated power spectrum from supernovae lensing magnification are also
derived and compared with theoretical expectations.


title: On the Capacity of the Multiuser Vector Adder Channel

abstract:
  We investigate the capacity of the $Q$-frequency $S$-user vector adder
channel (channel with intensity information) introduced by Chang and Wolf. Both
coordinated and uncoordinated types of transmission are considered. Asymptotic
(under the conditions $Q \to \infty$, $S = \gamma Q$ and $0 < \gamma < \infty$)
upper and lower bounds on the relative (per subchannel) capacity are derived.
The lower bound for the coordinated case is shown to increase when $\gamma$
grows. At the same time the relative capacity for the uncoordinated case is
upper bounded by a constant.


title:
Maximum Throughput for a Cognitive Radio Multi-Antenna User with
  Multiple Primary Users

abstract:
  We investigate a cognitive radio scenario involving a single cognitive
transmitter equipped with $\mathcal{K}$ antennas sharing the spectrum with
$\mathcal{M}$ primary users (PUs) transmitting over orthogonal bands. Each
terminal has a queue to store its incoming traffic. We propose a novel protocol
where the cognitive user transmits its packet over a channel formed by the
aggregate of the inactive primary bands. We study the impact of the number of
PUs, sensing errors, and the number of antennas on the maximum secondary stable
throughput.


title:
Upper Bounds on the Minimum Distance of Quasi-Cyclic LDPC codes
  Revisited

abstract:
  Two upper bounds on the minimum distance of type-1 quasi-cyclic low-density
parity-check (QC LDPC) codes are derived. The necessary condition is given for
the minimum code distance of such codes to grow linearly with the code length.


title:
Emotional Responses in Artificial Agent-Based Systems: Reflexivity and
  Adaptation in Artificial Life

abstract:
  The current work addresses a virtual environment with self-replicating agents
whose decisions are based on a form of "somatic computation" (soma - body) in
which basic emotional responses, taken in parallelism to actual living
organisms, are introduced as a way to provide the agents with greater reflexive
abilities. The work provides a contribution to the field of Artificial
Intelligence (AI) and Artificial Life (ALife) in connection to a
neurobiology-based cognitive framework for artificial systems and virtual
environments' simulations. The performance of the agents capable of emotional
responses is compared with that of self-replicating automata, and the
implications of research on emotions and AI, in connection to both virtual
agents as well as robots, is addressed regarding possible future directions and
applications.


title: New integrable (3+1)-dimensional systems and contact geometry

abstract:
  We introduce a novel systematic construction for integrable (3+1)-dimensional
dispersionless systems using nonisospectral Lax pairs that involve contact
vector fields.
  In particular, we present new large classes of (3+1)-dimensional integrable
dispersionless systems associated to the Lax pairs which are polynomial and
rational in the spectral parameter.

categories: math.AP hep-th math-ph math.DG math.MP nlin.SI


title: Spectral triples and finite summability on Cuntz-Krieger algebras

abstract:
  We produce a variety of odd bounded Fredholm modules and odd spectral triples
on Cuntz-Krieger algebras by means of realizing these algebras as "the algebra
of functions on a non-commutative space" coming from a sub shift of finite
type. We show that any odd $K$-homology class can be represented by such an odd
bounded Fredholm module or odd spectral triple. The odd bounded Fredholm
modules that are constructed are finitely summable. The spectral triples are
$\theta$-summable although their bounded transform, when constructed using the
sign-function, will already on the level of analytic $K$-cycles be finitely
summable bounded Fredholm modules. Using the unbounded Kasparov product, we
exhibit a family of generalized spectral triples, possessing mildly unbounded
commutators, whilst still giving well defined $K$-homology classes.


title:
Stanley--Reisner rings of generalised truncation polytopes and their
  moment-angle manifolds

abstract:
  We consider simple polytopes
$P=vc^{k}(\Delta^{n_{1}}\times\ldots\times\Delta^{n_{r}})$, for
$n_1\ge\ldots\ge n_r\ge 1,r\ge 1,k\ge 0$, that is, $k$-vertex cuts of a product
of simplices, and call them {\emph{generalized truncation polytopes}}. For
these polytopes we describe the cohomology ring of the corresponding
moment-angle manifold $\mathcal Z_P$ and explore some topological consequences
of this calculation. We also examine minimal non-Golodness for their
Stanley--Reisner rings and relate it to the property of $\mathcal Z_P$ being a
connected sum of sphere products.


title: Exponential-Krylov methods for ordinary differential equations

abstract:
  This paper develops a new class of exponential-type integrators where all the
matrix exponentiations are performed in a single Krylov space of low dimension.
The new family, called Lightly Implicit Krylov-Exponential (LIKE), is well
suited for solving large scale systems of ODEs or semi-discrete PDEs. The time
discretization and the Krylov space approximation are treated as a single
computational process, and the Krylov space properties are an integral part of
the new LIKE order condition theory developed herein. Consequently, LIKE
methods require a small number of basis vectors determined solely by the
temporal order of accuracy. The subspace size is independent of the ODE under
consideration, and there is no need to monitor the errors in linear system
solutions at each stage. Numerical results illustrate the favorable properties
of new family of methods.


title: Editorial

abstract:
  Clauset and Woodard (2013) ask, "What is the likelihood of another September
11th-sized or larger terrorist event, worldwide, over the next decade?" This
question has implications for numerous policy arenas - national security,
international relations, public safety, disaster preparedness, and so on - but
it also has resonance for any individual who remembers 9/11. Thus, the Area
Editors chose this paper to engage the audience at the 2013 Joint Statistical
Meetings (JSM) in Montreal. The discussions in this issue of The Annals of
Applied Statistics include those presented formally at JSM 2013 as well as
others from individuals who were unable to attend JSM 2013 or who contributed
discussions after the meeting.


title:
Spanning Properties of Yao and $\Theta$-Graphs in the Presence of
  Constraints

abstract:
  We present improved upper bounds on the spanning ratio of constrained
$\theta$-graphs with at least 6 cones and constrained Yao-graphs with 5 or at
least 7 cones. Given a set of points in the plane, a Yao-graph partitions the
plane around each vertex into $m$ disjoint cones, each having aperture $\theta
= 2 \pi/m$, and adds an edge to the closest vertex in each cone. Constrained
Yao-graphs have the additional property that no edge properly intersects any of
the given line segment constraints. Constrained $\theta$-graphs are similar to
constrained Yao-graphs, but use a different method to determine the closest
vertex.
  We present tight bounds on the spanning ratio of a large family of
constrained $\theta$-graphs. We show that constrained $\theta$-graphs with $4k
+ 2$ ($k \geq 1$ and integer) cones have a tight spanning ratio of $1 + 2
\sin(\theta/2)$, where $\theta$ is $2 \pi / (4k + 2)$. We also present improved
upper bounds on the spanning ratio of the other families of constrained
$\theta$-graphs. These bounds match the current upper bounds in the
unconstrained setting.
  We also show that constrained Yao-graphs with an even number of cones ($m
\geq 8$) have spanning ratio at most $1 / ( 1 - 2 \sin (\theta/2) )$ and
constrained Yao-graphs with an odd number of cones ($m \geq 5$) have spanning
ratio at most $1 / ( 1 - 2 \sin (3\theta/8) )$. As is the case with constrained
$\theta$-graphs, these bounds match the current upper bounds in the
unconstrained setting, which implies that like in the unconstrained setting
using more cones can make the spanning ratio worse.


title: Accelerated FRW Solutions in Chern-Simons Gravity

abstract:
  We consider a five-dimensional Einstein-Chern-Simons action which is composed
of a gravitational sector and a sector of matter, where the gravitational
sector is given by a Chern-Simons gravity action instead of the
Einstein-Hilbert action and where the matter sector is given by the so called
perfect fluid. It is shown that (i) the Einstein-Chern-Simons (EChS) field
equations subject to suitable conditions can be written in a similar way to the
Einstein-Maxwell field equations; (ii) these equations have solutions that
describe accelerated expansion for the three possible cosmological models of
the universe, namely, spherical expansion, flat expansion and hyperbolic
expansion when $\alpha $, a parameter of theory, is greater than zero. This
result allow us to conjeture that this solutions are compatible with the era of
Dark Energy and that the energy-momentum tensor for the field $h^{a}$, a
bosonic gauge field from the Chern-Simons gravity action, corresponds to a form
of positive cosmological constant.
  It is also shown that the EChS field equations have solutions compatible with
the era of matter: (i) In the case of an open universe, the solutions
correspond to an accelerated expansion ($\alpha >0$) with a minimum scale
factor at initial time that, when the time goes to infinity, the scale factor
behaves as a hyperbolic sine function. (ii) In the case of a flat universe, the
solutions describing an accelerated expansion whose scale factor behaves as a
exponencial function when time grows. \item In the case of a closed universe it
is found only one solution for a universe in expansion, which behaves as a
hyperbolic cosine function when time grows.


title:
Mutual diffusion of inclusions in freely-suspended smectic liquid
  crystal films

abstract:
  We study experimentally and theoretically the hydrodynamic interaction of
pairs of circular inclusions in two-dimensional, fluid smectic membranes
suspended in air. By analyzing their Brownian motion, we find that the radial
mutual mobilities of identical inclusions are independent of their size but
that the angular coupling becomes strongly size-dependent when their radius
exceeds a characteristic hydrodynamic length. The observed dependence of the
mutual mobilities on inclusion size is described well for arbitrary separations
by a model that generalizes the Levine/MacKintosh theory of point-force
response functions and uses a boundary-element approach to calculate the
mobility matrix.