title:
A single step protein assay that is both detergent and reducer
  compatible: The cydex blue assay

abstract:
  Determination of protein concentration in often an absolute pre-requisite in
preparing samples for biochemical and proteomic analyses. However, current
protein assay methods are not compatible with both reducers and detergents,
which are however present simultaneously in most denaturing extraction buffers
used in proteomics and electrophoresis, and in particular in SDS
electrophoresis. We found that inclusion of cyclodextrins in a Coomassie
blue-based assay made it compatible with detergents, as cyclodextrins complex
detergents in a 1:1 molecular ratio. As this type of assay is intrinsically
resistant to reducers, we have thus developed a single step assay that is both
detergent and reducer compatible. Depending on the type and concentration of
detergents present in the sample buffer, either beta-cyclodextrin or
alpha-cyclodextrin can be used, the former being able to complex a wider range
of detergents and the latter being able to complex higher amounts of detergents
due to its greater solubility in water. Cyclodextrins are used at final
concentrations of 2-10 mg/mL in the assay mix. This typically allows to measure
samples containing as little as 0.1 mg/mL protein, in the presence of up to 2%
detergent and reducers such as 5 % mercaptoethanol or 50 mM DTT in a single
step with a simple spectrophotometric assay. This article is protected by
copyright. All rights reserved.


title:
Studying how trainee teachers use an online learning environment:
  resituating interviews supported by digital traces

abstract:
  This article is an empirical contribution to the field of educational
technology but also - and above all - a methodological contribution to the
analysis of the activities enacted in this field. It takes account of a pilot
study conducted within the framework of doctoral research and consisted in
describing, analysing and modelling the activity of a trainee teacher in a
situation of autonomous use of a video-based digital learning environment
(DLE). We were particularly careful to describe the method in great detail. Two
types of data were collected and processed within the framework of
"course-of-action": (i)activity observation data (dynamic screen capture) and
(ii) data from resituating interviews supported by digital traces of that
activity. The findings (i) validate the method's relevance in relation to the
object and issues of the research, (ii)show different levels of organization in
the activity deployed in the situation of use, (iii) highlight four registers
of concerns orienting use of the DLE. We conclude from a perspective of
educational technology, by discussing how, according to certain conditions and
different time scales, the findings inform a process of continuous DLE design.


title:
Scattering states of Dirac particle equation with position dependent
  mass under the cusp potential

abstract:
  We solved the one-dimensional position-dependent mass Dirac equation in the
presence of the cusp potential and reported the solutions in terms of the
Whittaker functions. We have derived the reflection and transmission
coefficients by making use of the matching conditions on the wave functions.
The effect of position dependent mass on the reflection and transmission
coefficients of the system is duly investigated.


title: The inverse scattering problem by an elastic inclusion

abstract:
  In this work we consider the inverse elastic scattering problem by an
inclusion in two dimensions. The elastic inclusion is placed in an isotropic
homogeneous elastic medium. The inverse problem, using the third Betti's
formula (direct method), is equivalent to a system of four integral equations
that are non linear with respect to the unknown boundary. Two equations are on
the boundary and two on the unit circle where the far-field patterns of the
scattered waves lie. We solve iteratively the system of integral equations by
linearising only the far-field equations. Numerical results are presented that
illustrate the feasibility of the proposed method.


title: Satellites of spherical subgroups

abstract:
  Let $G$ be a complex connected reductive algebraic group. Given a spherical
subgroup $H \subset G$ and a subset $I$ of the set of spherical roots of $G/H$,
we define, up to conjugation, a spherical subgroup $H_I \subset G$ of the same
dimension of $H$, called a satellite. We investigate various interpretations of
the satellites. We also show a close relation between the Poincar\'{e}
polynomials of the two spherical homogeneous spaces $G/H$ and $G/H_I$.


title:
The dynamic polarization potential and dynamical non-locality in nuclear
  potentials: Deuteron-nucleus potential

abstract:
  The consequences for direct reactions of the dynamical non-locality generated
by the excitation of the target and projectile are much less studied than the
effects of non-locality arising from exchange processes. Here we are concerned
with the dynamical non-locality due to projectile excitation in deuteron
induced reactions. The consequences of this non-locality can be studied by the
comparison of deuteron induced direct reactions calculated with alternative
representations of the elastic channel wave functions: (i) the elastic channel
wave functions from coupled channel (CC) calculations involving specific
reaction processes, and, (ii) elastic channel wave functions calculated from
local potentials that exactly reproduce the elastic scattering $S$-matrix from
the same CC calculations. In this work we produce the local equivalent deuteron
potentials required for the study of direct reactions involving deuterons.
These will enable the study of the effects of dynamical non-locality following
a method previously employed in an investigation of the effects of non-locality
due to target excitation. In this work we consider only excitations due to
deuteron breakup, and some new properties of the breakup dynamical polarization
potential (DPP) emerge that reveal dynamical non-locality directly. In
addition, we evaluate the TELP inversion method and find that it fails to
reproduce some features of the DPP due to breakup.


title:
Truncated Variance Reduction: A Unified Approach to Bayesian
  Optimization and Level-Set Estimation

abstract:
  We present a new algorithm, truncated variance reduction (TruVaR), that
treats Bayesian optimization (BO) and level-set estimation (LSE) with Gaussian
processes in a unified fashion. The algorithm greedily shrinks a sum of
truncated variances within a set of potential maximizers (BO) or unclassified
points (LSE), which is updated based on confidence bounds. TruVaR is effective
in several important settings that are typically non-trivial to incorporate
into myopic algorithms, including pointwise costs and heteroscedastic noise. We
provide a general theoretical guarantee for TruVaR covering these aspects, and
use it to recover and strengthen existing results on BO and LSE. Moreover, we
provide a new result for a setting where one can select from a number of noise
levels having associated costs. We demonstrate the effectiveness of the
algorithm on both synthetic and real-world data sets.


title:
A Novel Learning Algorithm for B\"uchi Automata based on Family of DFAs
  and Classification Trees

abstract:
  In this paper, we propose a novel algorithm to learn a B\"uchi automaton from
a teacher who knows an $\omega$-regular language. The algorithm is based on
learning a formalism named family of DFAs (FDFAs) recently proposed by Angluin
and Fisman[10]. The main catch is that we use a classification tree structure
instead of the standard observation table structure. The worst case storage
space required by our algorithm is quadratically better than the table-based
algorithm proposed in [10]. We implement the first publicly available library
ROLL (Regular Omega Language Learning ), which consists of all $\omega$-regular
learning algorithms available in the literature and the new algorithms proposed
in this paper. Experimental results show that our tree-based algorithms have
the best performance among others regarding the number of solved learning
tasks.


title: Theoretical Analysis of Active Contours on Graphs

abstract:
  Active contour models based on partial differential equations have proved
successful in image segmentation, yet the study of their geometric formulation
on arbitrary geometric graphs is still at an early stage. In this paper, we
introduce geometric approximations of gradient and curvature, which are used in
the geodesic active contour model. We prove convergence in probability of our
gradient approximation to the true gradient value and derive an asymptotic
upper bound for the error of this approximation for the class of random
geometric graphs. Two different approaches for the approximation of curvature
are presented and both are also proved to converge in probability in the case
of random geometric graphs. We propose neighborhood-based filtering on graphs
to improve the accuracy of the aforementioned approximations and define two
variants of Gaussian smoothing on graphs which include normalization in order
to adapt to graph non-uniformities. The performance of our active contour
framework on graphs is demonstrated in the segmentation of regular images and
geographical data defined on arbitrary graphs.


title:
Temperature dependent giant resistance anomaly in LaAlO3/SrTiO3
  nanostructures

abstract:
  The resistance of the electron gas at the interface between the two band
insulators LaAlO3 (LAO) and SrTiO3 (STO) typically drops monotonically with
temperature and R/T curves during cooling and warm-up look identical for large
area structures. Here we show that if the LAO/STO is laterally restricted by
nanopatterning the resistance exhibits a temperature anomaly. Warming up
nanostructures from low temperatures leads to one or two pronounced resistance
peaks between 50 and 100 K not observed for larger dimensions. During cool-down
current filaments emerge at the domain walls that form during the well-known
structural phase transition of the STO substrate. During warm-up the reverse
phase transition can interrupt filaments before the sheet conductivity which
dominates at higher temperature is reestablished. Due to the limited number of
filaments in a nanostructure this process can result in a complete loss of
conductance. As a consequence of these findings the transport physics extracted
from experiments in small and large area LAO/STO structures may need to be
reconsidered.


title:
Cutoff phenomenon for the asymmetric simple exclusion process and the
  biased card shuffling

abstract:
  We consider the biased card shuffling and the Asymmetric Simple Exclusion
Process (ASEP) on the segment. We obtain the asymptotic of their mixing times:
our result show that these two continuous-time Markov chains display cutoff.
Our analysis combines several ingredients including: a study of the
hydrodynamic profile for ASEP, the use of monotonic eigenfunctions, stochastic
comparisons and concentration inequalities.


title:
On Solving Non-preemptive Mixed-criticality Match-up Scheduling Problem
  with Two and Three Criticality Levels

abstract:
  In this paper, we study an NP-hard problem of a single machine scheduling
minimizing the makespan, where the mixed-critical tasks with an uncertain
processing time are scheduled. We show the derivation of F-shaped tasks from
the probability distribution function of the processing time, then we study the
structure of problems with two and three criticality levels for which we
propose efficient exact algorithms and we present computational experiments for
instances with up to 200 tasks. Moreover, we show that the considered problem
is approximable within a constant multiplicative factor.


title:
Awakening the BALROG (BAyesian Location Reconstruction Of GRBs): A new
  paradigm in spectral and location analysis of gamma ray bursts

abstract:
  The accurate spatial location of gamma-ray bursts (GRBs) is crucial for both
producing a detector response matrix (DRM) and follow-up observations by other
instruments. The Fermi Gamma-ray Burst Monitor (GBM) has the largest field of
view (FOV) for detecting GRBs as it views the entire unocculted sky, but as a
non-imaging instrument it relies on the relative count rates observed in each
of its 14 detectors to localize transients. Improving its ability to accurately
locate GRBs and other transients is vital to the paradigm of multi-messenger
astronomy, including the electromagnetic follow-up of gravitational wave
signals. Here we present the BAyesian Location Reconstruction Of GRBs ({\tt
BALROG}) method for localizing and characterising GBM transients. Our approach
eliminates the systematics of previous approaches by simultaneously fitting for
the location and spectrum of a source. It also correctly incorporates the
uncertainties in the location of a transient into the spectral parameters and
produces reliable positional uncertainties for both well-localized sources and
those for which the GBM data cannot effectively constrain the position. While
computationally expensive, {\tt BALROG} can be implemented to enable quick
follow-up of all GBM transient signals. Also, we identify possible response
problems that require attention as well as caution when using standard, public
GBM DRMs. Finally, we examine the effects of including the variance in location
on the spectral parameters of GRB 080916C. We find that spectral parameters
change and no extra components are required when these effects are included in
contrast to when we use a fixed location. This finding has the potential to
alter both the GRB spectral catalogs as well as the reported spectral
composition of some well-known GRBs.


title:
An Efficient Adaptive Boundary Matching Algorithm for Video Error
  Concealment

abstract:
  Sending compressed video data in error-prone environments (like the Internet
and wireless networks) might cause data degradation. Error concealment
techniques try to conceal the received data in the decoder side. In this paper,
an adaptive boundary matching algorithm is presented for recovering the damaged
motion vectors (MVs). This algorithm uses an outer boundary matching or
directional temporal boundary matching method to compare every boundary of
candidate macroblocks (MBs), adaptively. It gives a specific weight according
to the accuracy of each boundary of the damaged MB. Moreover, if each of the
adjacent MBs is already concealed, different weights are given to the
boundaries. Finally, the MV with minimum adaptive boundary distortion is
selected as the MV of the damaged MB. Experimental results show that the
proposed algorithm can improve both objective and subjective quality of
reconstructed frames without any considerable computational complexity. The
average PSNR in some frames of test sequences increases about 5.20, 5.78, 5.88,
4.37, 4.41, and 3.50 dB compared to average MV, classic boundary matching,
directional boundary matching, directional temporal boundary matching, outer
boundary matching, and dynamical temporal error concealment algorithm,
respectively.


title: QoE-aware Scalable Video Transmission in MIMO~Systems

abstract:
  An important concept in wireless systems has been quality of experience
(QoE)-aware video transmission. Such communications are considered not only
connection-based communications but also content-aware communications, since
the video quality is closely related to the content itself. It becomes
necessary therefore for video communications to utilize a cross-layer design
(also known as joint source and channel coding). To provide efficient methods
of allocating network resources, the wireless network uses its cross-layer
knowledge to perform unequal error protection (UEP) solutions. In this article,
we summarize the latest video transmission technologies that are based on
scalable video coding (SVC) over multiple-input multiple-output (MIMO) systems
with cross-layer designs. To provide insight into video transmission in
wireless networks, we investigate UEP solutions in the delivering of video over
massive MIMO systems. Our results show that in terms of quality of experience
(QoE), SVC layer prioritization, which was considered important in the prior
work, is not always beneficial in massive MIMO systems; consideration must be
given to the content characteristics.


title:
Characterization of an inconsistency ranking for pairwise comparison
  matrices

abstract:
  Pairwise comparisons between alternatives are a well-known method for
measuring preferences of a decision-maker. Since these often do not exhibit
consistency, a number of inconsistency indices has been introduced in order to
measure the deviation from this ideal case. We axiomatically characterize the
inconsistency ranking induced by the Koczkodaj inconsistency index: six
independent properties are presented such that they determine a unique linear
order on the set of all pairwise comparison matrices.


title: Transforming a matrix into a standard form

abstract:
  We show that every matrix all of whose entries are in a fixed subgroup of the
group of units of a commutative ring with identity is equivalent to a standard
form. As a consequence, we improve the proof of Theorem 5 in D. Best, H.
Kharaghani, H. Ramp [Disc. Math. 313 (2013), 855--864].


title: A Practical Approach to Interval Refinement for math.h/cmath Functions

abstract:
  Verification of C++ programs has seen considerable progress in several areas,
but not for programs that use these languages' mathematical libraries. The
reason is that all libraries in widespread use come with no guarantees about
the computed results. This would seem to prevent any attempt at formal
verification of programs that use them: without a specification for the
functions, no conclusion can be drawn statically about the behavior of the
program. We propose an alternative to surrender. We introduce a pragmatic
approach that leverages the fact that most math.h/cmath functions are almost
piecewise monotonic: as we discovered through exhaustive testing, they may have
glitches, often of very small size and in small numbers. We develop interval
refinement techniques for such functions based on a modified dichotomic search,
that enable verification via symbolic execution based model checking, abstract
interpretation, and test data generation. Our refinement algorithms are the
first in the literature to be able to handle non-correctly rounded function
implementations, enabling verification in the presence of the most common
implementations. We experimentally evaluate our approach on real-world code,
showing its ability to detect or rule out anomalous behaviors.


title: Percolation results for the Continuum Random Cluster Model

abstract:
  The continuum random cluster model is a Gibbs modification of the standard
boolean model of intensity $z > 0$ and law of radii $Q$. The formal unormalized
density is given by $q^{N_{cc}}$ where $q$ is a fixed parameter and $N_{cc}$ is
the number of connected components in the random structure. We prove for a
large class of parameters that percolation occurs for $z$ large enough and does
not occur for $z$ small enough. An application to the phase transition of the
Widom-Rowlinson model with random radii is given. Our main tools are stochastic
domination properties, a fine study of the interaction of the model and a
Fortuin-Kasteleyn representation.


title: Generalized global symmetries and dissipative magnetohydrodynamics

abstract:
  The conserved magnetic flux of U(1) electrodynamics coupled to matter in four
dimensions is associated with a generalized global symmetry. We study the
realization of such a symmetry at finite temperature and develop the
hydrodynamic theory describing fluctuations of a conserved 2-form current
around thermal equilibrium. This can be thought of as a systematic derivation
of relativistic magnetohydrodynamics, constrained only by symmetries and
effective field theory. We construct the entropy current and show that at first
order in derivatives, there are seven dissipative transport coefficients. We
present a universal definition of resistivity in a theory of dynamical
electromagnetism and derive a direct Kubo formula for the resistivity in terms
of correlation functions of the electric field operator. We also study
fluctuations and collective modes, deriving novel expressions for the
dissipative widths of magnetosonic and Alfven modes. Finally, we demonstrate
that a non-trivial truncation of the theory can be performed at low
temperatures compared to the magnetic field: this theory has an emergent
Lorentz invariance along magnetic field lines, and hydrodynamic fluctuations
are now parametrized by a fluid tensor rather than a fluid velocity.
Throughout, no assumption is made of weak electromagnetic coupling. Thus, our
theory may have phenomenological relevance for dense electromagnetic plasmas.


title:
Record Counting in Historical Handwritten Documents with Convolutional
  Neural Networks

abstract:
  In this paper, we investigate the use of Convolutional Neural Networks for
counting the number of records in historical handwritten documents. With this
work we demonstrate that training the networks only with synthetic images
allows us to perform a near perfect evaluation of the number of records printed
on historical documents. The experiments have been performed on a benchmark
dataset composed by marriage records and outperform previous results on this
dataset.


title: Possibilities of Recursive GPU Mapping for Discrete Orthogonal Simplices

abstract:
  The problem of parallel thread mapping is studied for the case of discrete
orthogonal $m$-simplices. The possibility of a $O(1)$ time recursive
block-space map $\lambda: \mathbb{Z}^m \mapsto \mathbb{Z}^m$ is analyzed from
the point of view of parallel space efficiency and potential performance
improvement. The $2$-simplex and $3$-simplex are analyzed as special cases,
where constant time maps are found, providing a potential improvement of up to
$2\times$ and $6\times$ more efficient than a bounding-box approach,
respectively. For the general case it is shown that finding an efficient
recursive parallel space for an $m$-simplex depends of the choice of two
parameters, for which some insights are provided which can lead to a volume
that matches the $m$-simplex for $n>n_0$, making parallel space approximately
$m!$ times more efficient than a bounding-box.


title: Squares in Piatetski--Shapiro Sequences

abstract:
  We study the distribution of squares in a Piatetski-Shapiro sequence
$\left(\lfloor n^c\rfloor\right)_{n\in\mathbb N}$ with $c>1$ and
$c\not\in\mathbb N$. We also study more general equations $\lfloor{n^c}\rfloor
= sm^2$, $n,m\in \mathbb N$, $1\le n \le N$ for an integer $s$ and obtain
several bounds on the number of solutions for a fixed $s$ and on average over
$s$ in an interval. These results are based on various techniques chosen
depending on the range of the parameters.


title: Metrizing the Chabauty topology

abstract:
  We describe an explicit metric that induces the Chabauty topology on the
space of closed subsets of a proper metric space M.


title:
Brauer relations for finite groups in the ring of semisimplified modular
  representations

abstract:
  Let $G$ be a finite group and $p$ be a prime. We study the kernel of the map,
between the Burnside ring of $G$ and the Grothendieck ring of
$\mathbb{F}_p[G]$-modules, taking a $G$-set to its associated permutation
module. We are able, for all finite groups, to classify the primitive quotient
of the kernel; that is for each $G$, the kernel modulo elements coming from the
kernel for proper subquotients of $G$. We are able to identify exactly which
groups have non-trivial primitive quotient and we give generators for the
primitive quotient in the soluble case.


title: Contrast independent localization of multiscale problems

abstract:
  The accuracy of many multiscale methods based on localized computations
suffers from high contrast coefficients since the localization error generally
depends on the contrast. We study a class of methods based on the variational
multiscale method, where the range and kernel of a quasi-interpolation operator
defines the method. We present a novel interpolation operator for two-valued
coefficients and prove that it yields contrast independent localization error
under physically justified assumptions on the geometry of inclusions and
channel structures in the coefficient. The idea developed in the paper can be
transferred to more general operators and our numerical experiments show that
the contrast independent localization property follows.


title:
The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to
  Absolute Zero

abstract:
  Rapid cooling of liquids below a certain temperature range can result in a
transition to glassy states. The traditional understanding of glasses includes
their thermodynamic metastability with respect to crystals. However, here we
present specific examples of interactions that eliminate the possibilities of
crystalline and quasicrystalline phases, while creating mechanically stable
amorphous glasses down to absolute zero temperature. We show that this can be
accomplished by introducing a new ideal state of matter called a "perfect
glass." A perfect glass represents a soft-interaction analog of the maximally
random jammed (MRJ) packings of hard particles. These latter states can be
regarded as the epitome of a glass since they are out of equilibrium, maximally
disordered, hyperuniform, mechanically rigid with infinite bulk and shear
moduli, and can never crystallize due to configuration-space trapping. Our
model perfect glass utilizes two-, three-, and four-body soft interactions
while simultaneously retaining the salient attributes of the MRJ state. These
models constitute a theoretical proof of concept for perfect glasses and
broaden our fundamental understanding of glass physics. A novel feature of
equilibrium systems of identical particles interacting with the perfect-glass
potential at positive temperature is that they have a non-relativistic speed of
sound that is infinite.


title:
Convergent algorithm based on Carleman estimates for the recovery of a
  potential in the wave equation

abstract:
  This article develops the numerical and theoretical study of a reconstruction
algorithm of a potential in a wave equation from boundary measurements, using a
cost functional built on weighted energy terms coming from a Carleman estimate.
More precisely, this inverse problem for the wave equation consists in the
determination of an unknown time-independent potential from a single
measurement of the Neumann derivative of the solution on a part of the
boundary. While its uniqueness and stability properties are already well known
and studied, a constructive and globally convergent algorithm based on Carleman
estimates for the wave operator was recently proposed in [L. Baudouin, M. de
Buhan and S. Ervedoza, Global carleman estimates for waves and applications,
Comm. Partial Differential Equations 38 (2013), no. 5]. However, the numerical
implementation of this strategy still presents several challenges, that we
propose to address here.


title: Pale Glares of Dark Matter in Quantum Spacetime

abstract:
  A U(1) gauge theory turns, on physically motivated models of Quantum
Spacetime, into a U($\infty$) gauge theory, hence free classical
electrodynamics is no longer free and neutral fields may have electromagnetic
interactions. We discuss the last point for scalar fields, possibly describing
dark matter; we have in mind the gravitational collapse of binary systems or
future applications to self gravitating Bose-Einstein condensates as possible
sources of evidence of quantum gravitational phenomena. The effects so far
considered, however, seem too faint to be detectable at present.


title: Consistency of the Planck CMB data and $\Lambda$CDM cosmology

abstract:
  We test the consistency between Planck temperature and polarization power
spectra and the concordance model of $\Lambda$ Cold Dark Matter cosmology
($\Lambda$CDM) within the framework of Crossing statistics. We find that Planck
TT best fit $\Lambda$CDM power spectrum is completely consistent with EE power
spectrum data while EE best fit $\Lambda$CDM power spectrum is not consistent
with TT data. However, this does not point to any systematic or model-data
discrepancy since in the Planck EE data, uncertainties are much larger compared
to the TT data. We also investigate the possibility of any deviation from
$\Lambda$CDM model analyzing the Planck 2015 data. Results from TT, TE and EE
data analysis indicate that no deviation is required beyond the flexibility of
the concordance $\Lambda$CDM model. Our analysis thus rules out any strong
evidence for beyond the concordance model in the Planck spectra data. We also
report a mild amplitude difference comparing temperature and polarization data,
where temperature data seems to have slightly lower amplitude than expected
(consistently at all multiples), as we assume both temperature and polarization
data are realizations of the same underlying cosmology.


title: The Function-on-Scalar LASSO with Applications to Longitudinal GWAS

abstract:
  We present a new methodology for simultaneous variable selection and
parameter estimation in function-on-scalar regression with an ultra-high
dimensional predictor vector. We extend the LASSO to functional data in both
the $\textit{dense}$ functional setting and the $\textit{sparse}$ functional
setting. We provide theoretical guarantees which allow for an exponential
number of predictor variables. Simulations are carried out which illustrate the
methodology and compare the sparse/functional methods. Using the Framingham
Heart Study, we demonstrate how our tools can be used in genome-wide
association studies, finding a number of genetic mutations which affect blood
pressure and are therefore important for cardiovascular health.


title:
Measurement-Based Wideband Analysis of Dynamic Multipath Propagation in
  Vehicular Communication Scenarios

abstract:
  Realistic propagation modeling requires a detailed understanding and
characterization of the radio channel properties. This paper is based on
channel sounder measurements with 1 GHz bandwidth at a carrier frequency of 5.7
GHz and particular tracking methods. We present statistical models for the
number of, birth rate, lifetime, excess delay and relative Doppler frequency of
individual multipath components (MPCs). Our findings are concluded from 72
measurement runs in eight relevant vehicular communication scenarios and reveal
wide insights into the dynamic propagation process in vehicular communication
scenarios.


title:
Tracking of Wideband Multipath Components in a Vehicular Communication
  Scenario

abstract:
  A detailed understanding of the dynamic processes of vehicular radio channels
is crucial for its realistic modeling. In this paper, we present multipath
components (MPCs) tracking results from a channel sounder measurement with 1
GHz bandwidth at a carrier frequency of 5.7 GHz. We describe in detail the
applied algorithms and perform a tracking performance evaluation based on
artificial channels and on measurement data from a tunnel scenario. The
tracking performance of the proposed algorithm is comparable to the tracking
performance of the state-of-the-art Gaussian mixture probability hypothesis
density filter, yet with a significantly lower complexity. The fluctuation of
the measured channel gain is followed very well by the proposed tracking
algorithm, with a power loss of only 2.5 dB. We present statistical
distributions for the number of MPCs and the birth/death rate. The applied
algorithms and tracking results can be used to enhance the development of
geometry-based channel models.


title: Combination with anti-tit-for-tat remedies problems of tit-for-tat

abstract:
  One of the most important questions in game theory concerns how mutual
cooperation can be achieved and maintained in a social dilemma. In Axelrod's
tournaments of the iterated prisoner's dilemma, Tit-for-Tat (TFT) demonstrated
the role of reciprocity in the emergence of cooperation. However, the stability
of TFT does not hold in the presence of implementation error, and a TFT
population is prone to neutral drift to unconditional cooperation, which
eventually invites defectors. We argue that a combination of TFT and anti-TFT
(ATFT) overcomes these difficulties in a noisy environment, provided that ATFT
is defined as choosing the opposite to the opponent's last move. According to
this TFT-ATFT strategy, a player normally uses TFT; turns to ATFT upon
recognizing his or her own error; returns to TFT either when mutual cooperation
is recovered or when the opponent unilaterally defects twice in a row. The
proposed strategy provides simple and deterministic behavioral rules for
correcting implementation error in a way that cannot be exploited by the
opponent, and suppresses the neutral drift to unconditional cooperation.


title:
C-mix: a high dimensional mixture model for censored durations, with
  applications to genetic data

abstract:
  We introduce a mixture model for censored durations (C-mix), and develop
maximum likelihood inference for the joint estimation of the time distributions
and latent regression parameters of the model. We consider a high-dimensional
setting, with datasets containing a large number of biomedical covariates. We
therefore penalize the negative log-likelihood by the Elastic-Net, which leads
to a sparse parameterization of the model. Inference is achieved using an
efficient Quasi-Newton Expectation Maximization (QNEM) algorithm, for which we
provide convergence properties. We then propose a score by assessing the
patients risk of early adverse event. The statistical performance of the method
is examined on an extensive Monte Carlo simulation study, and finally
illustrated on three genetic datasets with high-dimensional covariates. We show
that our approach outperforms the state-of-the-art, namely both the CURE and
Cox proportional hazards models for this task, both in terms of C-index and
AUC(t).


title: Congruence classes of triangles in $\mathbb{F}_p^2$

abstract:
  In this short note, we give a lower bound on the number of congruence classes
of triangles in a small set of points in $\mathbb{F}_p^2$. More precisely, for
$\mathcal{A}\subset \mathbb{F}_p^2$ with $|\mathcal{A}|\le p^{2/3}$, we prove
that the number of congruence classes of triangles determined by points in
$\mathcal{A}\times \mathcal{A}$ is at least $|\mathcal{A}|^{7/2}$. This note is
not intended for journal publication.


title: Coarse and fine geometry of the Thurston metric

abstract:
  We study the geometry of the Thurston metric on the Teichm\"uller space
$\mathcal{T}(S)$ of hyperbolic structures on a surface $S$. Some of our results
on the coarse geometry of this metric apply to arbitrary surfaces $S$ of finite
type; however, we focus particular attention on the case where the surface is a
once-punctured torus, $S_{1,1}$. In that case, our results provide a detailed
picture of the infinitesimal, local, and global behavior of the geodesics of
the Thurston metric, as well as an analogue of Royden's theorem.


title: From Event-B to Verified C via HLL

abstract:
  This work addresses the correct translation of an Event-B model to C code via
an intermediate formal language, HLL. The proof of correctness follows two main
steps. First, the final refinement of the Event-B model, including invariants,
is translated to HLL. At that point, additional properties (e.g.,
deadlock-freeness, liveness properties, etc.) are added to the HLL model. The
proof of the invariants and additional properties at the HLL level guarantees
the correctness of the translation. Second, the C code is automatically
generated from the HLL model for most of the system functions and manually for
the remaining ones; in this case, the HLL model provides formal contracts to
the software developer. An equivalence proof between the C code and the HLL
model guarantees the correctness of the code.


title:
Dynamics of Particles Around a Regular Black Hole with Nonlinear
  Electrodynamics

abstract:
  We investigate the dynamics of a charged particle being kicked off from its
circular orbit around a regular black hole by an incoming massive particle in
the presence of magnetic field. The resulting escape velocity, escape energy
and the effective potential is analyzed. It is shown that the presence of even
a very weak magnetic field helps the charged particles in escaping the
gravitational field of the black hole. Moreover the effective force acting on
the particle visibly reduces with distance. Thus particle near the black hole
will experience higher effective force as compared to when it is far away.


title: Chiral transition, eigenmode localisation and Anderson-like models

abstract:
  We discuss chiral symmetry restoration and eigenmode localisation in
finite-temperature QCD by looking at the lattice Dirac operator as a random
Hamiltonian. We argue that the features of QCD relevant to both phenomena are
the presence of order in the Polyakov line configuration, and the correlations
that this induces between spatial links across time slices. This ties the fate
of chiral symmetry and of localisation of the lowest Dirac eigenmodes to the
confining properties of the theory. We then show numerical results obtained in
a QCD-inspired Anderson-like toy model, derived by radically simplifying the
QCD dynamics while keeping the important features mentioned above. The toy
model reproduces all the important qualitative aspects of chiral symmetry
breaking and localisation in QCD, thus supporting the central role played by
the confinement/deconfinement transition in triggering both phenomena.


title:
P-i-n InGaN homojunctions (10-40% In) synthesized by plasma-assisted
  molecular beam epitaxy with extended photoresponse to 600 nm

abstract:
  We report the influence of the In mole fraction on the material and
electrical characteristics of p-i-n InxGa1-xN homojunctions (x = 0.10-0.40)
synthesized by plasma-assisted molecular-beam epitaxy on GaN-on-sapphire
substrates. Junctions terminated with p-InGaN present improved carrier
extraction efficiency in comparison with devices capped with p-GaN, due to the
deleterious effect of polarization discontinuities on the device performance.
We demonstrate that the presence of Mg does not perturb the In incorporation in
InGaN, and it leads to a significant reduction of the stacking fault density.
p-In0.3Ga0.7N layers with a hole concentration of 3.2x1018 cm-3 are
demonstrated. InGaN homojunction devices show a peak EQE = 14+-2% in the
blue-to-orange spectral region, and an extended cutoff to 600 nm.


title: 3D Chern-Simons Term breaks Meissner Effect

abstract:
  It is well-known that (2+1)-dimensional Chern-Simons term may lead to
topological Meissner effect. However, we show that 3-dimensional Chern-Simons
term, which is different from (2+1)-dimensional Chern-Simons term, will instead
destroy traditional Meissner effect. This means that the presence of a
3-dimensional Chern-Simons term naturally guarantees the validity of
"pre-formed pairs" picture explaining high-T_c superconductivity, because such
a term breaks Meissner effect induced by paired electrons. In particular, if
3-dimensional Chern-Simons gauge fields indeed emerge in the "pre-formed pairs"
regime, our theory predicts that around the transition temperature T_c the Hall
conductivity {\sigma} should exhibit a scaling law {\sigma}->(T-T_c )^(2/D)
with D being the dimension of the superconducting material.


title:
A microscopic two-band model for the electron-hole asymmetry in
  high-$T_c$ superconductors and reentering behavior

abstract:
  We present here a microscopic two-band model based on the structure of
energetic levels of holes in $\mathrm{CuO}_{2}$ conducting layers of cuprates.
We prove that two energetically near-lying interacting bands can explain the
electron-hole asymmetry. Indeed, we rigorously analyze the phase diagram of the
model and show that the critical temperatures for fermion densities below
half-filling can manifest a very different behavior as compared to the case of
densities above half-filling. This fact results from the inter-band interaction
and intra-band Coulomb repulsion in interplay with thermal fluctuations between
two energetic levels. So, if the energy difference between bands is too big
then the asymmetry disappears. Moreover, the critical temperature turns out to
be a non-monotonic function of the fermion density and the phase diagram of our
model shows "superconducting domes" as in high-$T_{c}$ cuprate superconductors.
This explains why the maximal critical temperature is attained at donor
densities away from the maximal one. Outside the superconducting phase and for
fermion densities near half-filling the thermodynamics governed by our
Hamiltonian corresponds, as in real high-$T_c$ materials, to a Mott-insulating
phase. The nature of the inter-band interaction can be electrostatic (screened
Coulomb interaction), magnetic (for instance some Heisenberg-type one-site
spin-spin interaction), or a mixture of both. If the inter-band interaction is
predominately magnetic then - additionally to the electron-hole asymmetry - we
observe a reentering behavior meaning that the superconducting phase can only
occur in a finite interval of temperatures. This phenomenon is rather rare, but
has also been observed in the so-called magnetic superconductors.


title:
d-Wave Pairing Driven by Bipolaric Modes Related to Giant
  Electron-Phonon Anomalies in High-$T_{c}$ Superconductors

abstract:
  Taking into account microscopic properties of most usual high-$T_{c}$
superconductors, like cuprates, we define a class of microscopic model
Hamiltonians for two fermions (electrons or holes) and one boson (bipolaron) on
the two-dimensional square lattice. We establish that these model Hamiltonians
can show d-wave paring at the bottom of their spectrum, despite their space
isotropy. This phenomenon appear when a "giant electron-phonon anomaly" is
present at the boundaries of the Brillouin zone ("half breathing"
bond-stretching mode), like in doped cuprates. Our results can be used to
derive effective electron-electron interactions mediated by bipolarons and we
discuss regimes where the corresponding model is relevant for the physics of
high-temperature superconductivity and can be mathematically rigorously
studied.


title:
Fast-light Enhanced Brillouin Laser Based Active Fiber Optics Sensor for
  Simultaneous Measurement of Rotation and Acceleration

abstract:
  We have developed a conceptual design for an Active Fast Light Fiber Optic
Sensor (AFLIFOS) that can perform simultaneously or separately as a gyroscope
(differential mode effect) and a sensor for acceleration, strain, and other
common mode effects. Two Brillouin lasers in opposite directions and separated
in frequency by several free spectral ranges are used for this sensor. By
coupling two auxiliary resonators to the primary fiber resonator, we produce
superluminal effects for two laser modes. We develop a detailed theoretical
model for optimizing the design of the AFLIFOS, and show that the enhancement
factor of the sensitivity is $\sim{187}$ and $\sim{-187}$, respectively for the
two Brillouin lasers under the optimized condition, when the effective change
in perimeter of the primary fiber resonator is 0.1nm, corresponding to a
rotation rate of 0.4 deg/sec for a ring resonator with radius 1m. It may be
possible to get much higher enhancement by adjusting the parameters such as the
perimeters and the coupling coefficients.


title: Statistical Machine Translation for Indian Languages: Mission Hindi

abstract:
  This paper discusses Centre for Development of Advanced Computing Mumbai's
(CDACM) submission to the NLP Tools Contest on Statistical Machine Translation
in Indian Languages (ILSMT) 2014 (collocated with ICON 2014). The objective of
the contest was to explore the effectiveness of Statistical Machine Translation
(SMT) for Indian language to Indian language and English-Hindi machine
translation. In this paper, we have proposed that suffix separation and word
splitting for SMT from agglutinative languages to Hindi significantly improves
over the baseline (BL). We have also shown that the factored model with
reordering outperforms the phrase-based SMT for English-Hindi (\enhi). We
report our work on all five pairs of languages, namely Bengali-Hindi (\bnhi),
Marathi-Hindi (\mrhi), Tamil-Hindi (\tahi), Telugu-Hindi (\tehi), and \enhi for
Health, Tourism, and General domains.


title: Using Machine Learning to Detect Noisy Neighbors in 5G Networks

abstract:
  5G networks are expected to be more dynamic and chaotic in their structure
than current networks. With the advent of Network Function Virtualization
(NFV), Network Functions (NF) will no longer be tightly coupled with the
hardware they are running on, which poses new challenges in network management.
Noisy neighbor is a term commonly used to describe situations in NFV
infrastructure where an application experiences degradation in performance due
to the fact that some of the resources it needs are occupied by other
applications in the same cloud node. These situations cannot be easily
identified using straightforward approaches, which calls for the use of
sophisticated methods for NFV infrastructure management. In this paper we
demonstrate how Machine Learning (ML) techniques can be used to identify such
events. Through experiments using data collected at real NFV infrastructure, we
show that standard models for automated classification can detect the noisy
neighbor phenomenon with an accuracy of more than 90% in a simple scenario.


title: Reordering rules for English-Hindi SMT

abstract:
  Reordering is a preprocessing stage for Statistical Machine Translation (SMT)
system where the words of the source sentence are reordered as per the syntax
of the target language. We are proposing a rich set of rules for better
reordering. The idea is to facilitate the training process by better alignments
and parallel phrase extraction for a phrase-based SMT system. Reordering also
helps the decoding process and hence improving the machine translation quality.
We have observed significant improvements in the translation quality by using
our approach over the baseline SMT. We have used BLEU, NIST, multi-reference
word error rate, multi-reference position independent error rate for judging
the improvements. We have exploited open source SMT toolkit MOSES to develop
the system.


title: Modelling and Computing Homotopy Types: I

abstract:
  The aim of this article is to explain a philosophy for applying higher
dimensional Seifert-van Kampen Theorems, and how the use of groupoids and
strict higher groupoids resolves some foundational anomalies in algebraic
topology at the border between homology and homotopy. We explain some
applications to filtered spaces, and special cases of them, while a sequel will
show the relevance to n-cubes of pointed spaces.


title:
Reduced Loop Quantization with four Klein-Gordon Scalar Fields as
  Reference Matter

abstract:
  We perform a reduced phase space quantization of gravity using four
Klein-Gordon scalar fields as reference matter as an alternative to the
Brown-Kuchar dust model in [1], where dust scalar fields are used. We compare
our results to an earlier model by Domagala et. al. [2] where only one
Klein-Gordon scalar field is considered as reference matter for the Hamiltonian
constraint but the spatial diffeomorphism constraints are quantized using Dirac
quantization. As a result we find that the choice of four conventional
Klein-Gordon scalar fields as reference matter leads to a reduced dynamical
model that cannot be quantized using loop quantum gravity techniques. However,
we further discuss a slight generalization of the action for the four
Klein-Gordon scalar fields and show that this leads to a model which can be
quantized in the framework of loop quantum gravity. By comparison of the
physical Hamiltonian operators obtained from the model by Domagala et. al. [2]
and the one introduced in this work we are able to make a first step towards
comparing Dirac and reduced phase space quantization in the context of the
spatial diffeomorphism constraints.


title:
Directed flow of $\Lambda$, $\bar{\Lambda}$, $K^{\pm}$, $K_S^0$ and
  $\phi$ mesons from Beam Energy Scan Au+Au collisions using the STAR
  experiment

abstract:
  We report the results of $v_1$ and $dv_1/dy$ near mid-rapidity for $\Lambda$,
$\bar{\Lambda}$, $K^{\pm}$, $K_s^0$ and $\phi$ in Au+Au collisions at
$\sqrt{s_{\rm NN}}$ = 7.7, 11.5, 14.5, 19.6, 27 and 39~GeV using the STAR
detector at RHIC. The $dv_1/dy$ of $\Lambda$ is found to be consistent with
that of the proton and shows a change in sign near $\sqrt{s_{\rm NN}} =
11.5$~GeV. The $v_{1}$ slope for $\bar{\Lambda}$, $\bar{p}$ and $\phi$ shows a
similar trend for $\sqrt{s_{\rm NN}}$ $>$ 14.5~GeV, while below 14.5~GeV,
$\phi$ $v_{1}$ is consistent with zero but with a large uncertainty. The
$dv_{1}/dy$ for net protons and net kaons is similar for $\sqrt{s_{\rm NN}} >$
14.5~GeV, but they deviate at lower beam energies.


title:
The poor altmetric performance of publications authored by researchers
  in mainland China

abstract:
  China's scientific output has risen precipitously over the past decade; it is
now the world's second-largest producer of scientific papers, behind only the
United States. The quality of China's research is also on the rise (Van
Noorden, 2016). The online visibility and impact of China's research are also
important issues worth exploring. In this study, we investigate the altmetric
performance of publications in the field of Biotechnology and Applied
Microbiology and published by authors from Chinese affiliations. We find that
papers published by those authors from Chinese affiliations have much lower
visibility on the social web than articles from other countries, when there is
no significant difference for the citations. Fewer of China's publications get
tweeted, and those tweeted publications attract less social attention. A
geographical analysis of tweeters shows that scholarly articles get most of
their social attention from the authors' home countries, a finding that is also
confirmed by correlation and regression analysis. This situation, which is
unfavorable for researchers from Chinese affiliations, is caused, in part, by
the inaccessibility of mainstream social networking platforms in mainland
China.


title: Quantum spin Hall effect in rutile-based oxide multilayers

abstract:
  Dirac points in two-dimensional electronic structures are a source for
topological electronic states due to the $\pm \pi$ Berry phase that they
sustain. Here we show that two rutile multilayers (namely
(WO$_2$)$_2$/(ZrO$_2$)$_n$ and (PtO$_2$)$_2$/(ZrO$_2$)$_n$, where an active
bilayer is sandwiched by a thick enough (n=6 is sufficient) band insulating
substrate, show semi-metallic Dirac dispersions with a total of four Dirac
cones along the $\Gamma-M$ direction. These become gapped upon the introduction
of spin-orbit coupling, giving rise to an insulating ground state comprising
four edge states. We discuss the origin of the lack of topological protection
in terms of the valley spin-Chern numbers and the multiplicity of Dirac points.
We show with a model Hamiltonian that mirror-symmetry breaking would be capable
of creating a quantum phase transition to a strong topological insulator, with
a single Kramers pair per edge.


title:
Dynamics of single human embryonic stem cells and their pairs: a
  quantitative analysis

abstract:
  Numerous biological approaches are available to characterise the mechanisms
which govern the formation of human embryonic stem cell (hESC) colonies. To
understand how the kinematics of single and pairs of hESCs impact colony
formation, we study their mobility characteristics using time-lapse imaging. We
perform a detailed statistical analysis of their speed, survival,
directionality, distance travelled and diffusivity. We confirm that single and
pairs of cells migrate as a diffusive random walk. Moreover, we show that the
presence of Cell Tracer significantly reduces hESC mobility. Our results open
the path to employ the theoretical framework of the diffusive random walk for
the prognostic modelling and optimisation of the growth of hESC colonies.
Indeed, we employ this random walk model to estimate the seeding density
required to minimise the occurrence of hESC colonies arising from more than one
founder cell and the minimal cell number needed for successful colony
formation. We believe that our prognostic model can be extended to investigate
the kinematic behaviour of somatic cells emerging from hESC differentiation and
to enable its wide application in phenotyping of pluripotent stem cells for
large scale stem cell culture expansion and differentiation platforms.


title:
EAS data at the mountain level and a shape of the CR spectrum beyond the
  break

abstract:
  In the most works which deal with EAS the CR energy spectrum is deduced by
means of the model defined dependence $E_0=a\cdot{N_e}^{\alpha}$. An electron
total number $N_e$ is evaluated by integration of the NKG-function f(r). This
algorithm breaks down for young EAS with age parameter $s\sim0$. This work
shows, that part of the young EAS becomes large in the range $N_e\geq10^7$, it
cause to divergency of the $N_e$ integral for them and distorts the shape of
EAS (CR) spectrum. A final analysis of the experimental data permits to
conclude that EAS spectrum has local maximum at $N_e\sim10^9$, which results in
a decrease of the EAS spectrum slope for $N_e\geq10^7$ (inverse break or
"knee"). A local maximum can arise because of the additional CR component in
the range $E_0\geq10$ PeV.


title: 6-dimensional FJRW theories of the simple-elliptic singularities

abstract:
  We give explicitly in the closed formulae the genus zero primary potentials
of the three 6-dimensional FJRW theories of the simple-elliptic singularity
$\tilde E_7$ with the non-maximal symmetry groups. For each of these FJRW
theories we establish the CY/LG correspondence to the Gromov-Witten theory of
the orbifold $[\mathcal{E}/ (\mathbb{Z}/2\mathbb{Z})]$ --- the orbifold
quotient of the elliptic curve by the hyperelliptic involution. Namely, we give
explicitly the Givental's group elements, whose actions on the partition
function of the Gromov--Witten theory of $[\mathcal{E}/
(\mathbb{Z}/2\mathbb{Z})]$ give up to a linear change of the variables the
partition functions of the FJRW theories mentioned. We keep track of the linear
changes of the variables needed. We show that using only the axioms of
Fan--Jarvis--Ruan, the genus zero potential can only be reconstructed up to a
scaling.


title: Fluctuations around mean walking behaviours in diluted pedestrian flows

abstract:
  Understanding and modeling the dynamics of pedestrian crowds can help with
designing and increasing the safety of civil facilities. A key feature of
crowds is its intrinsic stochasticity, appearing even under very diluted
conditions, due to the variability in individual behaviours. Individual
stochasticity becomes even more important under densely crowded conditions,
since it can be nonlinearly magnified and may lead to potentially dangerous
collective behaviours. To understand quantitatively crowd stochasticity, we
study the real-life dynamics of a large ensemble of pedestrians walking
undisturbed, and we perform a statistical analysis of the fully-resolved
pedestrian trajectories obtained by a year-long high-resolution measurement
campaign. Our measurements have been carried out in a corridor of the Eindhoven
University of Technology via a combination of Microsoft Kinect 3D-range sensor
and automatic head-tracking algorithms. The temporal homogeneity of our large
database of trajectories allows us to robustly define and separate average
walking behaviours from fluctuations parallel and orthogonal with respect to
the average walking path. Fluctuations include rare events when individuals
suddenly change their minds and invert their walking direction. Such tendency
to invert direction has been poorly studied so far even if it may have
important implications on the functioning and safety of facilities. We propose
a novel model for the dynamics of undisturbed pedestrians, based on stochastic
differential equations, that provides a good agreement with our experimental
observations, including the occurrence of rare events.


title: Coalescence on the real line

abstract:
  We study a geometrically constrained coalescence model derived from spin
systems. Given two probability distributions $\mathbb{P}_R$ and $\mathbb{P}_B$
on the positive reals with finite means, colour the real line alternately with
red and blue intervals so that the lengths of the red intervals have
distribution $\mathbb{P}_R$, the lengths of the blue intervals have
distribution $\mathbb{P}_B$, and distinct intervals have independent lengths.
Now, iteratively update this colouring of the line by coalescing intervals:
change the colour of any interval that is surrounded by longer intervals so
that these three consecutive intervals subsequently form a single monochromatic
interval. We say that a colour (either red or blue) wins if every point of the
line is eventually of that colour. Holroyd, in 2011, asked the following
question: under what natural conditions on the initial distributions is one of
the colours almost surely guaranteed to win? It turns out that the answer to
this question can be quite counter-intuitive due to the non-monotone dynamics
of the model. In this paper, we investigate various notions of advantage one of
the colours might initially possess, and in the course of doing so, we
determine which of the two colours emerges victorious for various nontrivial
pairs of distributions.


title: Finite size scaling of random XORSAT

abstract:
  We consider a "configuration model" for random XORSAT which is a random
system of $n$ equations over $m$ variables in $\mathbb F_2$. Each equation is
of the form $y_1 + y_2 + \cdots + y_k = b$ where $k \geq 3$ is fixed, $y_1,
y_2, \cdots$ are variables (not necessarily distinct) and $b \in \mathbb F_2$.
The equations are chosen independently and uniformly at random with
replacement. It is known \cite{Dubois02, Dietzfelbinger10, pittel2016} that
there exists $\rho_k$ such that $m / n = \rho_k$ is a sharp threshold for the
satisfiability of this system. In this note we show that for the configuration
model, the width of SAT-UNSAT transition window for random $k$-XORSAT is
$\Theta(n^{-1/2})$ and also derive the exact scaling function.


title:
Virtual Embodiment: A Scalable Long-Term Strategy for Artificial
  Intelligence Research

abstract:
  Meaning has been called the "holy grail" of a variety of scientific
disciplines, ranging from linguistics to philosophy, psychology and the
neurosciences. The field of Artifical Intelligence (AI) is very much a part of
that list: the development of sophisticated natural language semantics is a
sine qua non for achieving a level of intelligence comparable to humans.
Embodiment theories in cognitive science hold that human semantic
representation depends on sensori-motor experience; the abundant evidence that
human meaning representation is grounded in the perception of physical reality
leads to the conclusion that meaning must depend on a fusion of multiple
(perceptual) modalities. Despite this, AI research in general, and its
subdisciplines such as computational linguistics and computer vision in
particular, have focused primarily on tasks that involve a single modality.
Here, we propose virtual embodiment as an alternative, long-term strategy for
AI research that is multi-modal in nature and that allows for the kind of
scalability required to develop the field coherently and incrementally, in an
ethically responsible fashion.


title:
On the generalized Langevin equation for a Rouse bead in a
  nonequilibrium bath

abstract:
  We present the reduced dynamics of a bead in a Rouse chain which is submerged
in a bath containing a driving agent that renders it out-of-equilibrium. We
first review the generalized Langevin equation of the middle bead in an
equilibrated bath. Thereafter, we introduce two driving forces. Firstly, we add
a constant force that is applied to the first bead of the chain. We investigate
how the generalized Langevin equation changes due to this perturbation for
which the system evolves towards a new equilibrium state after some time.
Secondly, we consider the case of stochastic active forces which will drive the
system to a nonequilibrium state. Including these active forces results in a
frenetic contribution to the second fluctuation-dissipation relation, in accord
with a recent extension of the fluctuation-dissipation relation to
nonequilibrium. The form of the frenetic term is analysed for the specific case
of Gaussian, exponentially correlated active forces. We also discuss the
resulting rich dynamics of the middle bead in which various regimes of normal
diffusion, subdiffusion and superdiffusion can be present.


title:
An Attempt to Design a Better Algorithm for the Uncapacitated Facility
  Location Problem

abstract:
  The uncapacitated facility location has always been an important problem due
to its connection to operational research and infrastructure planning. Byrka
obtained an algorithm that is parametrized by $\gamma$ and proved that it is
optimal when $\gamma>1.6774$. He also proved that the algorithm achieved an
approximation ratio of 1.50. A later work by Shi Li achieved an approximation
factor of 1.488. In this research, we studied these algorithms and several
related works. Although we didn't improve upon the algorithm of Shi Li, our
work did provide some insight into the problem. We also reframed the problem as
a vector game, which provided a framework to design balanced algorithms for
this problem.


title: Greedy Gaussian Segmentation of Multivariate Time Series

abstract:
  We consider the problem of breaking a multivariate (vector) time series into
segments over which the data is well explained as independent samples from a
Gaussian distribution. We formulate this as a covariance-regularized maximum
likelihood problem, which can be reduced to a combinatorial optimization
problem of searching over the possible breakpoints, or segment boundaries. This
problem can be solved using dynamic programming, with complexity that grows
with the square of the time series length. We propose a heuristic method that
approximately solves the problem in linear time with respect to this length,
and always yields a locally optimal choice, in the sense that no change of any
one breakpoint improves the objective. Our method, which we call greedy
Gaussian segmentation (GGS), easily scales to problems with vectors of
dimension over 1000 and time series of arbitrary length. We discuss methods
that can be used to validate such a model using data, and also to automatically
choose appropriate values of the two hyperparameters in the method. Finally, we
illustrate our GGS approach on financial time series and Wikipedia text data.


title:
Volume preserving non homogeneous mean curvature flow of convex
  hypersurfaces

abstract:
  We consider a convex Euclidean hypersurface that evolves by a volume or area
preserving flow with speed given by a general nonhomogeneous function of the
mean curvature. For a broad class of possible speed functions, we show that any
closed convex hypersurface converges to a round sphere. The proof is based on
the monotonicity of the isoperimetric ratio, which allows to control the inner
and outer radius of the hypersurface and to deduce uniform bounds on the
curvature by maximum principle arguments.


title:
Characterization of the proposed 4-{\alpha} cluster state candidate in
  16O

abstract:
  The $\mathrm{^{16}O}(\alpha, \alpha^{\prime})$ reaction was studied at
$\theta_{lab} = 0^\circ$ at an incident energy of $\textrm{E}_{lab}$ = 200 MeV
using the K600 magnetic spectrometer at iThemba LABS. Proton and $\alpha$-decay
from the natural parity states were observed in a large-acceptance
silicon-strip detector array at backward angles. The coincident charged
particle measurements were used to characterize the decay channels of the
$0_{6}^{+}$ state in $\mathrm{^{16}O}$ located at $E_{x} = 15.097(5)$ MeV. This
state is identified by several theoretical cluster calculations to be a good
candidate for the 4-$\alpha$ cluster state. The results of this work suggest
the presence of a previously unidentified resonance at $E_{x}\approx15$ MeV
that does not exhibit a $0^{+}$ character. This unresolved resonance may have
contaminated previous observations of the $0_{6}^{+}$ state.


title: Traffic gridlock on a honeycomb city

abstract:
  As a clear signature of modern urban design concepts, urban street networks
in dense populated zones are evolving nowadays towards grid-like layouts with
rectangular shapes, and most studies on traffic flow assume street networks as
square lattices. However, ideas from forgotten design schools bring unexplored
alternatives that might improve traffic flow in many circumstances. Inspired on
an old and almost in oblivion urban plan, we report the behavior of the
Biham-Middleton-Levine model (BML) \-- a paradigm for studying phase
transitions of traffic flow \-- on a hypothetical city with a perfect honeycomb
street network. In contrast with the original BML model on a square lattice,
the same model on a honeycomb does not show any anisotropy or intermediate
states, but a single continuous phase transition between free and totally
congested flow, a transition that can be completely characterized by the tools
of classical percolation. Although the transition occurs at a lower density
than for the conventional BML, simple modifications, like randomly stopping the
cars with a very small probability or increasing the traffic light periods,
drives the model to perform better on honeycomb lattices. As traffic lights and
disordered perturbations are inherent to real traffic, these results question
the actual role of the square grid-like designs and suggests the honeycombs as
an interesting alternative for urban planning in real cities.


title:
Parity doubling of nucleons and Delta baryons across the deconfinement
  phase transition

abstract:
  At zero temperature the negative-parity ground states of the nucleon and
delta baryons are non-degenerate with the positive-parity partners due to
spontaneous breaking of chiral symmetry. However, chiral symmetry is expected
to be restored at sufficiently high temperature, in particular when going from
the hadronic to the quark-gluon plasma (QGP) phase. This would imply that
channels with opposite parity become degenerate. We study the nucleon (spin
$1/2$) and $\Delta$ (spin $3/2$) baryons in both parity sectors using lattice
QCD. The range of temperatures spans both the hadronic and QGP phases. Using
the FASTSUM anisotropic $N_f = 2 + 1$ ensembles, we analyze the correlation
functions and the spectral functions using respectively exponential fits and
the Maximum Entropy Method. We find clear evidence of in-medium effects in the
hadronic phase, especially for the negative-parity ground state, and of parity
doubling in the QGP phase.


title: On the variation of the root number in families of elliptic curves

abstract:
  We show the density of rational points on non-isotrivial elliptic surfaces by
studying the variation of the root numbers among the fibers of these surfaces,
conditionally to two analytic number theory conjectures (the squarefree
conjecture and Chowla's conjecture). This is a weaker statement than the one
found in a preprint of Helfgott which proves (under the same assumptions) that
the average root number is $0$ when the surface admits a place of
multiplicative reduction. However, we use a different technique. The
conjectures involved impose a restriction on the degree of the irreducible
factors of the discriminant of the surfaces.
  Moreover, we manage to drop the squarefree conjecture assumption under some
technical hypotheses, and show thus unconditionally the variation of the root
number on many elliptic surfaces, without imposing a bound for the degree of
the irreducible factors. Under the parity conjecture, this guarantees the
density of the rational points on these surfaces.


title:
Kinematic equivalence between models driven by DBI field with constant
  $\gamma$ and exotic holographic quintessence cosmological models

abstract:
  We show the kinematic equivalence between cosmological models driven by
Dirac-Born-Infeld fields $\phi$ with constant proper velocity of the brane and
exponential potential $V=V_0e^{-B\phi}$ and interactive cosmological systems
with Modified Holographic Ricci type fluids as dark energy in flat
Friedmann-Robertson-Walker cosmologies.


title:
Deep Multi-scale Location-aware 3D Convolutional Neural Networks for
  Automated Detection of Lacunes of Presumed Vascular Origin

abstract:
  Lacunes of presumed vascular origin (lacunes) are associated with an
increased risk of stroke, gait impairment, and dementia and are a primary
imaging feature of the small vessel disease. Quantification of lacunes may be
of great importance to elucidate the mechanisms behind neuro-degenerative
disorders and is recommended as part of study standards for small vessel
disease research. However, due to the different appearance of lacunes in
various brain regions and the existence of other similar-looking structures,
such as perivascular spaces, manual annotation is a difficult, elaborative and
subjective task, which can potentially be greatly improved by reliable and
consistent computer-aided detection (CAD) routines.
  In this paper, we propose an automated two-stage method using deep
convolutional neural networks (CNN). We show that this method has good
performance and can considerably benefit readers. We first use a fully
convolutional neural network to detect initial candidates. In the second step,
we employ a 3D CNN as a false positive reduction tool. As the location
information is important to the analysis of candidate structures, we further
equip the network with contextual information using multi-scale analysis and
integration of explicit location features. We trained, validated and tested our
networks on a large dataset of 1075 cases obtained from two different studies.
Subsequently, we conducted an observer study with four trained observers and
compared our method with them using a free-response operating characteristic
analysis. Shown on a test set of 111 cases, the resulting CAD system exhibits
performance similar to the trained human observers and achieves a sensitivity
of 0.974 with 0.13 false positives per slice. A feasibility study also showed
that a trained human observer would considerably benefit once aided by the CAD
system.


title:
Compact sorting of optical vortices by means of diffractive
  transformation optics

abstract:
  The orbital angular momentum (OAM) of light has recently attracted a growing
interest as a new degree of freedom in order to increase the information
capacity of today optical networks both for free-space and optical fiber
transmission. Here we present our work of design, fabrication and optical
characterization of diffractive optical elements for compact OAM-mode division
demultiplexing based on optical transformations. Samples have been fabricated
with 3D high-resolution electron beam lithography on polymethylmethacrylate
(PMMA) resist layer spun over a glass substrate. Their high compactness and
efficiency make these optical devices promising for integration into
next-generation platforms for OAM-modes processing in telecom applications.


title: Self-Polarizing Microswimmers in Active Density Waves

abstract:
  An artificial microswimmer drifts in response to spatio-temporal modulations
of an activating suspension medium. We consider two competing mechanisms
capable of influencing its tactic response: angular fluctuations, which help it
explore its surroundings and thus diffuse faster toward more active regions,
and self-polarization, a mechanism inherent to self-propulsion, which tends to
orient the swimmer's velocity parallel or antiparallel to the local activation
gradients. We investigate, both numerically and analytically, the combined
action of such two mechanisms. By determining their relative magnitude, we
characterize the selective transport of artificial microswimmers in
inhomogeneous activating media.


title: Noether Symmetry of Palatini $F(\Re)$ gravity

abstract:
  In metric formalism, Noether symmetry of F(R) theory of gravity in vacuum and
in the presence of pressureless dust yields $F(R)\propto R^\frac{3}{2}$ along
with the conserved current $\frac{d}{dt} (a\sqrt R)$ in Robertson-Walker metric
and nothing else. However, Roshan et.al. had claimed in $\mathrm{Phys. Lett.
\textbf{B668}, 238 (2008)}$ \cite{o} that Noether symmetry in the context of
Palatini $F(\Re)$ theory of gravity admits $F(\Re)\propto \Re^{s}$, (where $s$
is an arbitrary constant) in matter domain era in Friedmann- Robertson-Walker
universe. But, it has been shown that the conserved current obtained under the
process does not satisfy the field equations in general. Here, it is shown that
Noether Symmetry admits $F(\Re)\propto\Re^\frac{3}{2}$ along with a conserved
current $\Sigma_{0} {a}[\frac{\dot a}{a}+ \frac{\dot\Phi}{2\Phi}]$ in Palatini
gravity. Thus, their claim is not right.


title:
Calculated Structural and Electronic Interactions of the nano dye
  molecule $\rm Ru(4,\acute{4}-COOH-2,\acute{2}-bpy)_2(NCS)_2$($\rm N3$) with a
  iodide/triiodide redox shuttle

abstract:
  In this paper, dye sensitized solar cell based on nano dye molecule N3 are
investigated by using density functional computations. The main focus is on the
N3 dye molecule and corresponding complexes formed at the interface between
electrolyte and dye, during the regeneration process. The optimizaed geometry
and electronic structure of the molecule and complexs are calculated by using
the pseudopotential as well as full-potential techniques. The absorption
spectra of metalliferous dye molecule, N3, and its complexes are computed in
the framework of time dependent density functional theory. We determine the
reaction path of dye regeneration by Nudged Elastic Band (NEB) method. IR
spectrum of the N3 dye molecule were also calculated. We found that complexes
of N3 dye molecule and transition states formed in reactions, are magnetic.


title: Varieties of Boolean inverse semigroups

abstract:
  In an earlier work, the author observed that Boolean inverse semi-groups,
with semigroup homomorphisms preserving finite orthogonal joins, form a
congruence-permutable variety of algebras, called biases. We give a full
description of varieties of biases in terms of varieties of groups: (1) Every
free bias is residually finite. In particular, the word problem for free biases
is decidable. (2) Every proper variety of biases contains a largest finite
symmetric inverse semigroup, and it is generated by its members that are
generalized rook matrices over groups with zero. (3) There is an
order-preserving, one-to-one correspondence between proper varieties of biases
and certain finite sequences of varieties of groups, descending in a strong
sense defined in terms of wreath products by finite symmetric groups.


title: A Framework for Parallel and Distributed Training of Neural Networks

abstract:
  The aim of this paper is to develop a general framework for training neural
networks (NNs) in a distributed environment, where training data is partitioned
over a set of agents that communicate with each other through a sparse,
possibly time-varying, connectivity pattern. In such distributed scenario, the
training problem can be formulated as the (regularized) optimization of a
non-convex social cost function, given by the sum of local (non-convex) costs,
where each agent contributes with a single error term defined with respect to
its local dataset. To devise a flexible and efficient solution, we customize a
recently proposed framework for non-convex optimization over networks, which
hinges on a (primal) convexification-decomposition technique to handle
non-convexity, and a dynamic consensus procedure to diffuse information among
the agents. Several typical choices for the training criterion (e.g., squared
loss, cross entropy, etc.) and regularization (e.g., $\ell_2$ norm, sparsity
inducing penalties, etc.) are included in the framework and explored along the
paper. Convergence to a stationary solution of the social non-convex problem is
guaranteed under mild assumptions. Additionally, we show a principled way
allowing each agent to exploit a possible multi-core architecture (e.g., a
local cloud) in order to parallelize its local optimization step, resulting in
strategies that are both distributed (across the agents) and parallel (inside
each agent) in nature. A comprehensive set of experimental results validate the
proposed approach.


title:
Transverse Oscillations in Slender Ca II H Fibrils Observed with
  Sunrise/SuFI

abstract:
  We present observations of transverse oscillations in slender Ca II H fibrils
(SCFs) in the lower solar chromosphere. We use a 1 hr long time series of high-
(spatial and temporal-) resolution seeing-free observations in a 0.11 nm wide
passband covering the line core of Ca II H 396.9 nm from the second flight of
the Sunrise balloon-borne solar observatory. The entire field of view, spanning
the polarity inversion line of an active region close to the solar disk center,
is covered with bright, thin, and very dynamic fine structures. Our analysis
reveals the prevalence of transverse waves in SCFs with median amplitudes and
periods on the order of 2.4+-0.8 km/s and 83+-29 s, respectively (with standard
deviations given as uncertainties). We find that the transverse waves often
propagate along (parts of) the SCFs with median phase speeds of 9+-14 km/s.
While the propagation is only in one direction along the axis in some of the
SCFs, propagating waves in both directions, as well as standing waves are also
observed. The transverse oscillations are likely Alfvenic and are thought to be
representative of magnetohydrodynamic kink waves. The wave propagation suggests
that the rapid high-frequency transverse waves, often produced in the lower
photosphere, can penetrate into the chromosphere with an estimated energy flux
of ~ 15 kW/m^2. Characteristics of these waves differ from those reported for
other fibrillar structures, which, however, were observed mainly in the upper
solar chromosphere.


title: Modeling Crowd Dynamics through Hyperbolic - Elliptic Equations

abstract:
  Inspired by the works of Hughes [17, 18], we formalize and prove the well
posedness of a hyperbolic--elliptic system whose solutions describe the
dynamics of a moving crowd. The resulting model is here shown to be well posed
and the time of evacuation from a bounded environment is proved to be finite.
This model also provides a microscopic description of the individuals'
behaviors.


title:
Glass phase and other multiple liquid-to-liquid transitions resulting
  from two liquid phase competition

abstract:
  Melt supercooling leads to glass formation. Liquid-to-liquid phase
transitions are observed depending on thermal paths. Viscosity, density and
surface tension thermal dependences measured at heating and subsequent cooling
show hysteresis below a branching temperature and result from the competition
of two-liquid phases separated by an enthalpy difference depending on
temperature. The nucleation classical equation of these phases is completed by
this enthalpy saving existing at all temperatures. The glass phase
thermodynamic parameters and their thermal variation have already been
determined in such a two-liquid model. They are used at high temperatures to
predict liquid-to-liquid transitions in some metallic glass-forming melts.


title:
Localized electromechanical interactions in ferroelectric P(VDF-TrFE)
  nanowires investigated by scanning probe microscopy

abstract:
  We investigate the electromechanical interactions in individual P(VDF-TrFE)
nanowires in response to localized electrical poling via a conducting atomic
force microscope tip. Spatially resolved measurements of piezoelectric
coefficients and elastic moduli before and after poling reveal a striking
dependence on the polarity of the poling field, notably absent in thin films of
the same composition. These observations are attributed to the unclamped nature
of the nanowires and the inherent asymmetry in their chemical and electrical
interactions with the tip and underlying substrate. Our findings provide
insights into the mechanism of poling/switching in polymer nanowires critical
to ferroelectric device performance.


title:
Hybrid Quantile Regression Estimation for Time Series Models with
  Conditional Heteroscedasticity

abstract:
  Estimating conditional quantiles of financial time series is essential for
risk management and many other applications in finance. It is well-known that
financial time series display conditional heteroscedasticity. Among the large
number of conditional heteroscedastic models, the generalized autoregressive
conditional heteroscedastic (GARCH) process is the most popular and influential
one. So far, feasible quantile regression methods for this task have been
confined to a variant of the GARCH model, the linear GARCH model, owing to its
tractable conditional quantile structure. This paper considers the widely used
GARCH model. An easy-to-implement hybrid conditional quantile estimation
procedure is developed based on a simple albeit nontrivial transformation.
Asymptotic properties of the proposed estimator and statistics are derived,
which facilitate corresponding inferences. To approximate the asymptotic
distribution of the quantile regression estimator, we introduce a mixed
bootstrapping procedure, where a time-consuming optimization is replaced by a
sample averaging. Moreover, diagnostic tools based on the residual quantile
autocorrelation function are constructed to check the adequacy of the fitted
conditional quantiles. Simulation experiments are carried out to assess the
finite-sample performance of the proposed approach. The favorable performance
of the conditional quantile estimator and the usefulness of the inference tools
are further illustrated by an empirical application.


title:
A large-scale search for evidence of quasi-periodic pulsations in solar
  flares

abstract:
  The nature of quasi-periodic pulsations in solar flares is poorly
constrained, and critically the general prevalence of such signals in solar
flares is unknown. Therefore, we perform a large-scale search for evidence of
signals consistent with quasi-periodic pulsations in solar flares, focusing on
the 1 - 300s timescale. We analyse 675 M- and X-class flares observed by GOES
in 1-8\AA\ soft X-rays between 2011 February 1 and 2015 December 31.
Additionally, over the same era we analyse Fermi/GBM 15-25 keV X-ray data for
each of these flares that was associated with a Fermi/GBM solar flare trigger,
a total of 261 events. Using a model comparison method, we determine whether
there is evidence for a substantial enhancement in the Fourier power spectrum
that may be consistent with a QPP signature, based on three tested models; a
power-law plus a constant, a broken power-law plus constant, and a
power-law-plus-constant with an additional QPP signature component. From this,
we determine that ~30% of GOES events and ~8% of Fermi/GBM events show strong
signatures consistent with classical interpretations of QPP. For the remaining
events either two or more tested models cannot be strongly distinguished from
each other, or the events are well-described by single power-law or broken
power-law Fourier power spectra. For both instruments, a preferred
characteristic timescale of ~5-30 s was found in the QPP-like events, with no
dependence on flare magnitude in either GOES or GBM data. We also show that
individual events in the sample show similar characteristic timescales in both
GBM and GOES datasets. We discuss the implications of these results for our
understanding of solar flares and possible QPP mechanisms.


title: On the symmetry properties of the PT kernels and recurrence relations

abstract:
  Perturbation Theory to Large Scale Structure Cosmology proposes corrections
to the linearly evolved density contrast and velocity in terms of a series
development in which all terms are integrals of powers of the linear density
contrast multiplied by kernels. We discuss the symmetry properties of these
kernels and show that their full symmetrized versions can be decomposed in
different classes of subkernels. We will construct classes of subkernels with
improved symmetry properties, and provide recurrence relations to generate
them.


title: JLab Measurements of the 3He Form Factors at Large Momentum Transfers

abstract:
  The charge and magnetic form factors, FC and FM, of 3He have been extracted
in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering
by detecting 3He recoil nuclei and electrons in coincidence with the High
Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The
measurements are indicative of a second diffraction minimum for the magnetic
form factor, which was predicted in the Q2 range of this experiment, and of a
continuing diffractive structure for the charge form factor. The data are in
qualitative agreement with theoretical calculations based on realistic
interactions and accurate methods to solve the three-body nuclear problem.


title:
The effect of temperature dependent tissue parameters on acoustic
  radiation force induced displacements

abstract:
  Multiple ultrasound elastography techniques rely on acoustic radiation force
(ARF) in monitoring high-intensity focused ultrasound (HIFU) therapy. However,
ARF is dependent on tissue attenuation and sound speed, both of which are also
known to change with temperature making the therapy monitoring more
challenging. Furthermore, the viscoelastic properties of tissue are also
temperature dependent, which affects the displacements induced by ARF. The aim
of this study is to quantify the temperature dependent changes in the acoustic
and viscoelastic properties of liver and investigate their effect on ARF
induced displacements by using both experimental methods and simulations.
Furthermore, the temperature dependent viscoelastic properties of liver are
experimentally measured over a frequency range of 0.1-200 Hz at temperatures
reaching 80 C, and both conventional and fractional Zener models are used to
fit the data.
  The fractional Zener model was found to fit better with the experimental
viscoelasticity data with respect to the conventional model with up to two
magnitudes lower sum of squared errors (SSE). The characteristics of
experimental displacement data were also seen in the simulations due to the
changes in attenuation coefficient and lesion development. At low temperatures
before thermal ablation, attenuation was found to affect the displacement
amplitude. At higher temperature, the decrease in displacement amplitude occurs
approximately at 60-70 C due to the combined effect of viscoelasticity changes
and lesion growth overpowering the effect of attenuation. The results suggest
that it is necessary to monitor displacement continuously during HIFU therapy
in order to ascertain when ablation occurs.


title: Hashkat: Large-scale simulations of online social networks

abstract:
  Hashkat (http://hashkat.org) is a free, open source, agent based simulation
software package designed to simulate large-scale online social networks (e.g.
Twitter, Facebook, LinkedIn, etc). It allows for dynamic agent generation, edge
creation, and information propagation. The purpose of hashkat is to study the
growth of online social networks and how information flows within them. Like
real life online social networks, hashkat incorporates user relationships,
information diffusion, and trending topics. Hashkat was implemented in C++, and
was designed with extensibility in mind. The software includes Shell and Python
scripts for easy installation and usability. In this report, we describe all of
the algorithms and features integrated into hashkat before moving on to example
use cases. In general, hashkat can be used to understand the underlying
topology of social networks, validate sampling methods of such networks,
develop business strategy for advertising on online social networks, and test
new features of an online social network before going into production.


title: Optimistic Aborts for Geo-distributed Transactions

abstract:
  Network latency can have a significant impact on the performance of
transactional storage systems, particularly in wide area or geo-distributed
deployments. To reduce latency, systems typically rely on a cache to service
read-requests closer to the client. However, caches are not effective for
write-heavy workloads, which have to be processed by the storage system in
order to maintain serializability.
  This paper presents a new technique, called optimistic abort, which reduces
network latency for high-contention, write-heavy workloads by identifying
transactions that will abort as early as possible, and aborting them before
they reach the store. We have implemented optimistic abort in a system called
Gotthard, which leverages recent advances in network data plane programmability
to execute transaction processing logic directly in network devices. Gotthard
examines network traffic to observe and log transaction requests. If Gotthard
suspects that a transaction is likely to be aborted at the store, it aborts the
transaction early by re-writing the packet header, and routing the packets back
to the client. Gotthard significantly reduces the overall latency and improves
the throughput for high-contention workloads.


title:
Partial Wave Decomposition in Friedrichs Model With Self-interacting
  Continua

abstract:
  We consider the nonrelativistic model of coupling bare discrete states with
continuum states in which the continuum states can have interactions among
themselves. By partial-wave decomposition and constraint to the conserved
angular momentum eigenstates, the model can be reduced to Friedrichs-like model
with additional interactions between the continua. If a kind of factorizable
form factor is chosen, the model can be exactly solvable, that is, the
generalized discrete eigenstates including bound states, virtual states, and
resonances, can all be represented using the original bare states, and so do
the in-state and out-state. The exact $S$ matrix is thus obtained. We then
discuss the behaviors of the dynamically generated $S$-wave and $P$-wave
discrete states as the coupling is varying when there is only one
self-interacting bare continuum state. We find that even when the potential is
repulsive there could also be resonances and virtual states. In the $P$-wave
cases with attractive interaction, we find that when there is a near-threshold
bound state, there will always be an accompanying virtual state and we also
give a more general argument of this effect.


title:
Role of qubit-cavity entanglement for switching dynamics of quantum
  interfaces in superconductor metamaterials

abstract:
  We study quantum effects of strong driving field applied to dissipative
hybrid qubit-cavity system which are relevant for a realization of quantum
gates in superconducting quantum metamaterials. We demonstrate that effects of
strong and non-stationary drivings have significantly quantum nature and can
not be treated by means of mean-field approximation. This is shown from a
comparison of steady state solution of the standard Maxwell-Bloch equations and
numerical solution of Lindblad equation on a density matrix. We show that
mean-field approach provides very good agreement with the density matrix
solution at not very strong drivings $f<f^*$ but at $f>f^*$ a growing value of
quantum correlations between fluctuations in qubit and photon sectors changes a
behavior of the system. We show that in regime of non-adiabatic switching on of
the driving such a quantum correlations influence a dynamics of qubit and
photons even at weak $f$.


title:
Efficiency of the Keplerian accretion in the Braneworld Kerr--Newman
  Spacetimes and mining instability of some naked singularity spacetimes

abstract:
  We show that the~braneworld rotating Kerr--Newman black hole and naked
singularity spacetimes with both positive and negative braneworld tidal charge
parameter can be separated into fourteen classes according to properties of
circular geodesics governing the~Keplerian accretion. We determine efficiency
of the~Keplerian accretion disks for all braneworld Kerr--Newman spacetimes. We
demonstrate occurrence of an~infinitely deep gravitational potential in
Kerr--Newman naked singularity spacetimes having the~braneworld dimensionless
tidal charge $b \in (1/4,1)$ and the~dimensionless spin $a \in
(2\sqrt{b}-\sqrt{b(4b-1)},2\sqrt{b}+\sqrt{b(4b-1)})$, implying unbound
efficiency of the~Keplerian accretion and possibility to extract the~whole
naked singularity mass. Therefore, we call them braneworld "mining-unstable"
Kerr--Newman naked singularity spacetimes. Fundamental restriction on
the~relevance of the~extraordinary but fully classical phenomenon of the~mining
instability is given by validity of the~assumption of geodesic motion of
the~accreting matter.


title:
Astronomical Alignments of the Sun Temple site in Mesa Verde National
  Park

abstract:
  Summer 2015 marked the 100th anniversary of the excavation by J.W. Fewkes of
the Sun Temple in Mesa Verde National Park, Colorado; an ancient ceremonial
complex of unknown purpose, prominently located atop a mesa, constructed by the
Pueblo Indians approximately 1000 years ago. In this analysis we perform a
digital survey of the site, and examine the possibility that four key
tower-like elements of the complex were used for observation of the rise or set
of celestial bodies known to be sacred to the Pueblo Indians.
  We find statistically significant evidence that the site was used for
astronomical observation of the rise and/or set of nearly all such bodies. The
Sun Temple appears to represent the most comprehensive prehistoric astronomical
observatory yet uncovered.


title: Mapping Properties of Quadrature Domains in Several Complex Variables

abstract:
  We make use of the Bergman kernel function to study quadrature domains for
square-integrable holomorphic functions of several variables. Emphasis is given
to generalizing biholomorphic mapping properties of planar quadrature domains
to the several-dimensional setting.


title: Superconductivity and multiple pressure-induced phases in BaPt$_2$As$_2$

abstract:
  The newly discovered BaPt$_2$As$_2$ shows a structural distortion at around
275~K, followed by the emergence of superconductivity at lower temperatures.
Here we identify the presence of charge density wave (CDW) order at room
temperature and ambient pressure using single crystal x-ray diffraction, with
both a superlattice and an incommensurate modulation, where there is a change
of the superlattice structure below $\simeq$ 275~K. Upon applying pressure,
BaPt$_2$As$_2$ shows a rich temperature-pressure phase diagram with multiple
pressure-induced transitions at high temperatures, the emergence or
disappearance of which are correlated with sudden changes in the
superconducting transition temperature $T_c$. These findings demonstrate that
BaPt$_2$As$_2$ is a promising new system for studying competing interactions
and the relationship between high-temperature electronic instabilities and
superconductivity.


title: Archeology and evolution of QCD

abstract:
  These are excerpts from the closing talk at the "XIIth Conference on Quark
Confinement and the Hadron Spectrum", which took place last Summer in
Thessaloniki --an excellent place to enjoy an interest in archeology. A more
complete personal view of the early days of QCD and the rest of the Standard
Model is given in [1]. Here I discuss a few of the points which --to my
judgement-- illustrate well the QCD evolution (in time), both from a scientific
and a sociological point of view.


title:
A new look at scalar perturbations in loop quantum cosmology:
  (un)deformed algebra approach using self dual variables

abstract:
  Scalar cosmological perturbations in loop quantum cosmology (LQC) is
revisited in a covariant manner, using self dual Ashtekar variables. For
real-valued Ashtekar-Barbero variables, this `deformed algebra' approach has
been shown to implement holonomy corrections from loop quantum gravity (LQG) in
a consistent manner, albeit deforming the algebra of modified constraints in
the process. This deformation has serious conceptual ramifications, not the
least of them being an effective `signature-change' in the deep quantum regime.
In this paper, we show that working with self dual variables lead to an
undeformed algebra of hypersurface deformations, even after including holonomy
corrections in the effective constraints. As a necessary consequence, the
diffeomorphism constraint picks up non-perturbative quantum corrections thus
hinting at a modification of the underlying space-time structure, a novel
ingredient compared to the usual treatment of (spatial) diffeomorphisms in LQG.
This work extends a similar result obtained in the context of spherically
symmetric gravity coupled to a scalar field, suggesting that self dual
variables could be better suited than their real counterparts to treat
inhomogeneous LQG models.


title: Conditions on square geometric graphs

abstract:
  For any metric $d$ on $\mathbb{R}^2$, an ($\mathbb{R}^2,d$)-geometric graph
is a graph whose vertices are points in $\mathbb{R}^2$, and two vertices are
adjacent if and only if their distance is at most 1. If $d=\|.\|_{\infty}$, the
metric derived from the $L_{\infty}$ norm, then $(\mathbb{R}
^2,\|.\|_{\infty})$-geometric graphs are precisely those graphs that are the
intersection of two unit interval graphs. We refer to
$(\mathbb{R}^2,\|.\|_{\infty})$-geometric graphs as square geometric graphs. We
represent a characterization of square geometric graphs. Using this
characterization we provide necessary conditions for the class of square
geometric $B_{a,b}$-graphs, a generalization of cobipartite graphs. Then by
applying some restrictions on these necessary conditions we obtain sufficient
conditions for $B_{a,b}$-graphs to be square geometric.