title: Phase Transitions in the ASEP and Stochastic Six-Vertex Model

abstract:
  In this paper we consider two models in the Kardar-Parisi-Zhang (KPZ)
universality class, the asymmetric simple exclusion process (ASEP) and the
stochastic six-vertex model. We introduce a new class of initial data (which we
call {\itshape generalized step Bernoulli initial data}) for both of these
models that generalizes the step Bernoulli initial data studied in a number of
recent works on the ASEP. Under this class of initial data, we analyze the
current fluctuations of both the ASEP and stochastic six-vertex model and
establish the existence of a phase transition along a characteristic line,
across which the fluctuation exponent changes from $1 / 2$ to $1 / 3$. On the
characteristic line, the current fluctuations converge to the general (rank
$k$) Baik-Ben-Arous-P\'{e}ch\'{e} distribution for the law of the largest
eigenvalue of a critically spiked covariance matrix. For $k = 1$, this was
established for the ASEP by Tracy and Widom; for $k > 1$ (and also $k = 1$, for
the stochastic six-vertex model), the appearance of these distributions in both
models is new.


title: Projection-based filtering for stochastic reaction networks

abstract:
  This study concerns online inference (i.e., filtering) on the state of
reaction networks, conditioned on noisy and partial measurements. The
difficulty in deriving the equation that the conditional probability
distribution of the state satisfies stems from the fact that the master
equation, which governs the evolution of the reaction networks, is analytically
intractable. The linear noise approximation (LNA) technique, which is widely
used in the analysis of reaction networks, has recently been applied to develop
approximate inference. Here, we apply the projection method to derive
approximate filters, and compare them to a filter based on the LNA numerically
in their filtering performance. We also contrast the projection method with
moment-closure techniques in terms of approximating the evolution of stochastic
reaction networks.


title: A smooth variant of Hopkins-Singer differential K-theory

abstract:
  We introduce a smooth variant of the Hopkins-Singer model of differential
K-theory. We prove that our model is naturally isomorphic to the Hopkins-Singer
model and also to the Tradler-Wilson-Zeinalian model of differential K-theory.


title: Differentiating Infinite Voting Populations using Ultrafilters

abstract:
  In this short paper, we use the Rudin-Frolik order to shed light on the
differing structures of invisible dictatorships given by Arrow-type social
welfare functions over a countably infinite number of voters.


title:
Multiplicity distributions for $e^{+}e^{-}$ collisions using Weibull
  distribution

abstract:
  The two parameters Weibull function is used to describe the charged particle
multiplicity distribution in $e^{+}e^{-}$ collisions at the highest available
energy measured by TASSO and ALEPH experiments. The Weibull distribution has
wide applications in naturally evolving processes based on fragmentation and
sequential branching. The Weibull model describes the multiplicity distribution
very well, as particle production processes involve QCD parton fragmentation.
The effective energy model of particle production was verified using Weibull
parameters and the same was used to predict the multiplicity distribution in
$e^{+}e^{-}$ collisions at future collider energies.


title:
A rock-salt type Li-based oxide, Li3Ni2RuO6, exhibiting a chaotic
  ferrimagnetism with cluster spin-glass dynamics and thermally frozen charge
  carriers

abstract:
  The area of research to discover new Li containing materials and to
understand their physical properties has been of constant interest due to
applications potential for rechargeable batteries. Here, we present the results
of magnetic investigations on a Li compound, Li3Ni2RuO6, which was believed to
be a ferrimagnet below 80K. While our neutron diffraction (ND) and isothermal
magnetization (M) data support ferrimagnetism, more detailed magnetic studies
establish that this ferrimagnetic phase exhibits some features similar to
spin-glasses. In addition, we find another broad magnetic anomaly around 40-55
K in magnetic susceptibility, attributable to cluster spin-glass phenomenon.
Gradual dominance of cluster spin-glass dynamics with a decrease of temperature
(T) and the apparent spread in freezing temperature suggest that the
ferrimagnetism of this compound is a chaotic one. The absence of a unique
freezing temperature for a crystalline material is interesting. In addition,
pyroelectric current data reveals a feature in the range 40-50 K, attributable
to thermally stimulated depolarization current. We hope this finding motivates
future work to explore whether there is any intriguing correlation of such a
feature with spin-glass dynamics. We attribute these magnetic and electric
dipole anomalies to the crystallographic disorder intrinsic to this compound.


title:
The Inverse Problem for the Dirichlet-to-Neumann map on Lorentzian
  manifolds

abstract:
  We consider the Dirichlet-to-Neumann map $\Lambda$ on a cylinder-like
Lorentzian manifold related to the wave equation related to the metric $g$, a
magnetic field $A$ and a potential $q$. We show that we can recover the jet of
$g,A,q$ on the boundary from $\Lambda$ up to a gauge transformation in a stable
way. We also show that $\Lambda$ recovers the following three invariants in a
stable way: the lens relation of $g$, and the light ray transforms of $A$ and
$q$. Moreover, $\Lambda$ is an FIO away from the diagonal with a canonical
relation given by the lens relation. We present applications for recovery of
$A$ and $q$ in a logarithmically stable way in the Minkowski case, and
uniqueness with partial data.


title: A Non-Parametric Learning Approach to Identify Online Human Trafficking

abstract:
  Human trafficking is among the most challenging law enforcement problems
which demands persistent fight against from all over the globe. In this study,
we leverage readily available data from the website "Backpage"-- used for
classified advertisement-- to discern potential patterns of human trafficking
activities which manifest online and identify most likely trafficking related
advertisements. Due to the lack of ground truth, we rely on two human analysts
--one human trafficking victim survivor and one from law enforcement, for
hand-labeling the small portion of the crawled data. We then present a
semi-supervised learning approach that is trained on the available labeled and
unlabeled data and evaluated on unseen data with further verification of
experts.


title:
A Novel Bilingual Word Embedding Method for Lexical Translation Using
  Bilingual Sense Clique

abstract:
  Most of the existing methods for bilingual word embedding only consider
shallow context or simple co-occurrence information. In this paper, we propose
a latent bilingual sense unit (Bilingual Sense Clique, BSC), which is derived
from a maximum complete sub-graph of pointwise mutual information based graph
over bilingual corpus. In this way, we treat source and target words equally
and a separated bilingual projection processing that have to be used in most
existing works is not necessary any more. Several dimension reduction methods
are evaluated to summarize the BSC-word relationship. The proposed method is
evaluated on bilingual lexicon translation tasks and empirical results show
that bilingual sense embedding methods outperform existing bilingual word
embedding methods.


title: Connecting Phrase based Statistical Machine Translation Adaptation

abstract:
  Although more additional corpora are now available for Statistical Machine
Translation (SMT), only the ones which belong to the same or similar domains
with the original corpus can indeed enhance SMT performance directly. Most of
the existing adaptation methods focus on sentence selection. In comparison,
phrase is a smaller and more fine grained unit for data selection, therefore we
propose a straightforward and efficient connecting phrase based adaptation
method, which is applied to both bilingual phrase pair and monolingual n-gram
adaptation. The proposed method is evaluated on IWSLT/NIST data sets, and the
results show that phrase based SMT performance are significantly improved (up
to +1.6 in comparison with phrase based SMT baseline system and +0.9 in
comparison with existing methods).


title: Stochastic timing in gene expression for simple regulatory strategies

abstract:
  Timing is essential for many cellular processes, from cellular responses to
external stimuli to the cell cycle and circadian clocks. Many of these
processes are based on gene expression. For example, an activated gene may be
required to reach in a precise time a threshold level of expression that
triggers a specific downstream process. However, gene expression is subject to
stochastic fluctuations, naturally inducing an uncertainty in this
threshold-crossing time with potential consequences on biological functions and
phenotypes. Here, we consider such "timing fluctuations", and we ask how they
can be controlled. Our analytical estimates and simulations show that, for an
induced gene, timing variability is minimal if the threshold level of
expression is approximately half of the steady-state level. Timing fuctuations
can be reduced by increasing the transcription rate, while they are insensitive
to the translation rate. In presence of self-regulatory strategies, we show
that self-repression reduces timing noise for threshold levels that have to be
reached quickly, while selfactivation is optimal at long times. These results
lay a framework for understanding stochasticity of endogenous systems such as
the cell cycle, as well as for the design of synthetic trigger circuits.


title: Semi-supervised evidential label propagation algorithm for graph data

abstract:
  In the task of community detection, there often exists some useful prior
information. In this paper, a Semi-supervised clustering approach using a new
Evidential Label Propagation strategy (SELP) is proposed to incorporate the
domain knowledge into the community detection model. The main advantage of SELP
is that it can take limited supervised knowledge to guide the detection
process. The prior information of community labels is expressed in the form of
mass functions initially. Then a new evidential label propagation rule is
adopted to propagate the labels from labeled data to unlabeled ones. The
outliers can be identified to be in a special class. The experimental results
demonstrate the effectiveness of SELP.


title: Dynamics of a single-atom electron pump

abstract:
  Single-electron pumps based on isolated impurity atoms have recently been
experimentally demonstrated. In these devices the Coulomb potential of an atom
creates a localised electron state with a large charging energy and
considerable orbital level spacings, enabling robust charge capturing
processes. In these single-atom pumps, the confinement potential is hardly
affected by the periodic driving of the system. This is in contrast to the
often used gate-defined quantum dot pumps, for which a strongly time-dependent
potential leads to significantly different charge pumping processes. Here we
describe the behaviour and the performance of an atomic, single parameter,
electron pump. This is done by considering the loading, isolating and unloading
of one electron at the time, on a phosphorous atom embedded in a silicon double
gate transistor. The most important feature of the atom pump is its very
isolated ground state, which can be populated through the fast loading of much
higher lying excited states and a subsequent fast relaxation proces. This leads
to a substantial increase in pumping accuracy, and is opposed to the adverse
role of excited states as observed for quantum dot pumps due to non-adiabatic
excitations. The pumping performances are investigated as a function of dopant
position, revealing a pumping behaviour robust against the expected variability
in atomic position.


title:
Exploring the Sensitivity of Next Generation Gravitational Wave
  Detectors

abstract:
  The second-generation of gravitational-wave detectors are just starting
operation, and have already yielding their first detections. Research is now
concentrated on how to maximize the scientific potential of gravitational-wave
astronomy. To support this effort, we present here design targets for a new
generation of detectors, which will be capable of observing compact binary
sources with high signal-to-noise ratio throughout the Universe.


title:
The $\{\beta\}$-expansion formalism in perturbative QCD and its
  extension

abstract:
  We discuss the $\{ \beta \}$-expansion for renormalization group invariant
quantities tracing this expansion to the different contractions of the
corresponding incomplete BPHZ $R$-operation. All of the coupling
renormalizations, which follow from these contractions, should be taken into
account for the $\{ \beta \}$-expansion. We illustrate this feature considering
the nonsinglet Adler function $D^\text{NS}$ in the third order of perturbation.
We propose a generalization of the $\{ \beta \}$-expansion for the
renormalization group covariant quantities -- the $\{ \beta,\gamma
\}$-expansion.


title:
$\ell_1$-norm and entanglement in screening out braiding from
  Yang-Baxter equation associated with $\mathbb{Z}_3$ parafermion

abstract:
  The relationships between quantum entangled states and braid matrices have
been well studied in recent years. However, most of the results are based on
qubits. In this paper, We investigate the applications of 2-qutrit entanglement
in the braiding associated with $\mathbb{Z}_3$ parafermion. The 2-qutrit
entangled state $|\Psi(\theta)\rangle$, generated by acting the localized
unitary solution $\breve{R}(\theta)$ of YBE on 2-qutrit natural basis, achieves
its maximal $\ell_1$-norm and maximal von Neumann entropy simultaneously at
$\theta=\pi/3$. Meanwhile, at $\theta=\pi/3$, the solutions of YBE reduces
braid matrices, which implies the role of $\ell_1$-norm and entropy plays in
determining real physical quantities. On the other hand, we give a new
realization of 4-anyon topological basis by qutrit entangled states, then the
$9\times9$ localized braid representation in 4-qutrit tensor product space
$(\mathbb{C}^3)^{\otimes 4}$ are reduced to Jones representation of braiding in
the 4-anyon topological basis. Hence, we conclude that the entangled states are
powerful tools in analysing the characteristics of braiding and
$\breve{R}$-matrix.


title: Logarithmic coefficients of some close-to-convex functions

abstract:
  The logarithmic coefficients $\gamma_n$ of an analytic and univalent function
$f$ in the unit disk $\mathbb{D}=\{z\in\mathbb{C}:|z|<1\}$ with the
normalization $f(0)=0=f'(0)-1$ are defined by $\log \frac{f(z)}{z}=
2\sum_{n=1}^{\infty} \gamma_n z^n$. In the present paper, we consider
close-to-convex functions (with argument $0$) with respect to odd starlike
functions and determine the sharp upper bound of $|\gamma_n|$, $n=1,2,3$ for
such functions $f$.


title:
Structural and magnetic properties of Co-N thin films deposited using
  magnetron sputtering at 523 K

abstract:
  In this work, we studied cobalt nitride (Co-N) thin films deposited using a
dc magnetron sputtering method at a substrate temperature (\Ts) of 523\,K. We
find that independent of the reactive gas flow (\pn) used during sputtering,
the phases of Co-N formed at this temperature seems to be identical having N
\pat~$\sim$5. This is contrary to Co-N phases formed at lower \Ts. For
\Ts$\sim$300\,K, an evolution of Co-N phases starting from
Co(N)$\rightarrow$\tcn$\rightarrow$Co$_3$N$\rightarrow$CoN can be seen as \pn
increases to 100\p, whereas when the substrate temperature increases to 523\,K,
the phase formed is a mixture of Co and \tcn, independent of the {\pn} used
during sputtering. We used x-ray diffraction (XRD) to probe long range
ordering, x-ray absorption spectroscopy (XAS) at Co absorption edge for the
local structure, Magneto-optical Kerr e ffect (MOKE) and polarized neutron
reflectivity (PNR) to measure the magnetization of samples. Quantification of N
\pat~was done using secondary ion mass spectroscopy (SIMS). Measurements
suggest that the magnetic moment of Co-N samples deposited at 523\,K is
slightly higher than the bulk Co moment and does not get affected with the
\pn~used for reactive sputtering. Our results provide an important insight
about the phase formation of Co-N thin films which is discussed in this work.


title: Singularities of tangent surfaces to directed curves

abstract:
  A directed curve is a possibly singular curve with well-defined tangent lines
along the curve. Then the tangent surface to a directed curve is naturally
defined as the ruled surface by tangent geodesics to the curve, whenever any
affine connection is endowed with the ambient space. In this paper the local
diffeomorphism classification is completed for generic directed curves. Then it
turns out that the swallowtails and open swallowtails appear generically for
the classification on singularities of tangent surfaces.


title:
Multifunctional all-dielectric nano-optical systems using collective
  multipole Mie resonances: Towards on-chip integrated nanophotonics

abstract:
  We present an analysis of the optical response of a class of on-chip
integrated nano-photonic systems comprising all-dielectric building block based
multifunctional light manipulating units (LMU) integrated with quantum dot (QD)
light sources. The multiple functions (such as focusing excitation light, QD
emission rate enhancement, photon guidance, and lossless propagation) are
simultaneously realized using the collective Mie resonances of dipole and
higher order multipole modes of the dielectric building blocks (DBBs)
constituting a single structural unit, the LMU. Using analytical formulation
based on Mie theory we demonstrate enhancement of the excitation light
simultaneously with the guiding and propagation of the emitted light from a QD
emitter integrated with the DBB based LMU. The QD-DBB integrated structures can
serve as the basic element for building nano-optical active circuits for
optical information processing in both classical and quantum realms.


title:
The comparison Gelfand-Tsetlin-Molev and Gelfand-Tsetlin-Zhelobenko
  bases for $\mathfrak{sp}_{2n}$

abstract:
  A construction of Gelfand-Tsetlin type base vectors in a finite-dimensional
representation of $\mathfrak{sp}_{2n}$ was firstly obtained in 60-th by
Zhelobenko. But the final construction was obtained only in the year 1998 by
Molev, who gave a construction of Gelfand-Tsetlin type base vectors and derived
formulas for the action of generators of the algebra in this base. These two
approaches use different ideas.
  In the present paper we compare these two approaches. Also we show that the
Molev's base vectors can be obtained using a construction based on a relation
between restriction problems $\mathfrak{sp}_{2n}\downarrow\mathfrak{sp}_{2n-2}$
and $\mathfrak{gl}_{n+1}\downarrow\mathfrak{gl}_{n-1}$, analogous to the
construction giving the Zhelobenko's base.


title: Polynomials nonnegative on the cylinder

abstract:
  In 2010, Marshall settled the strip conjecture, according to which every
polynomial in $\mathbb{R}[x,y]$, nonnegative on the strip
$[-1,1]\times\mathbb{R}$, is a sum of squares and of squares times $1-x^2$. We
consider affine nonsingular curves $C$ over $\mathbb{R}$ with $C(\mathbb{R})$
compact, and study the question whether every $f$ in $\mathbb{R}[C][y]$,
nonnegative on $C(\mathbb{R})\times\mathbb{R}$, is a sum of squares in
$\mathbb{R}[C][y]$. We give an affirmative answer under the condition that $f$
has only finitely many zeros in $C(\mathbb{R})\times\mathbb{R}$. For $C$ the
circle $x_1^2+x_2^2=1$, we prove the result unconditionally.


title:
Mirror winding number and helical edge modes in honeycomb lattice with
  hopping-energy texture

abstract:
  We illustrate possible topological phases in honeycomb lattice with textures
in electron hopping energy between nearest-neighboring sites and show that they
are characterized by the mirror winding number intimately related to the chiral
(or sublattice) symmetry. Analytic wave functions of zero-energy edge modes in
ribbon geometry are provided, which are classified into even and odd sectors
with respect to the mirror operation with the mirror plane perpendicular to the
edge, and evolve into the topological helical edge states at finite momenta.
Intriguingly our results demonstrate that in order to achieve the topological
phase one can decorate the edge in a way adaptive to the bulk hopping texture.
This paves a new way to tailoring graphene in the topological point of view.


title:
Image Prediction for Limited-angle Tomography via Deep Learning with
  Convolutional Neural Network

abstract:
  Limited angle problem is a challenging issue in x-ray computed tomography
(CT) field. Iterative reconstruction methods that utilize the additional prior
can suppress artifacts and improve image quality, but unfortunately require
increased computation time. An interesting way is to restrain the artifacts in
the images reconstructed from the practical filtered back projection (FBP)
method. Frikel and Quinto have proved that the streak artifacts in FBP results
could be characterized. It indicates that the artifacts created by FBP method
have specific and similar characteristics in a stationary limited-angle
scanning configuration. Based on this understanding, this work aims at
developing a method to extract and suppress specific artifacts of FBP
reconstructions for limited-angle tomography. A data-driven learning-based
method is proposed based on a deep convolutional neural network. An end-to-end
mapping between the FBP and artifact-free images is learned and the implicit
features involving artifacts will be extracted and suppressed via nonlinear
mapping. The qualitative and quantitative evaluations of experimental results
indicate that the proposed method show a stable and prospective performance on
artifacts reduction and detail recovery for limited angle tomography. The
presented strategy provides a simple and efficient approach for improving image
quality of the reconstruction results from limited projection data.


title: Spin excitations in the skymion host Cu2OSeO3

abstract:
  We have used inelastic neutron scattering to measure the magnetic excitation
spectrum along the high-symmetry directions of the first Brillouin zone of the
magnetic skyrmion hosting compound Cu$_2$OSeO$_3$. The majority of our
scattering data are consistent with the expectations of a recently proposed
model for the magnetic excitations in Cu$_2$OSeO$_3$, and we report best-fit
parameters for the dominant exchange interactions. Important differences exist,
however, between our experimental findings and the model expectations. These
include the identification of two energy scales that likely arise due to
neglected anisotropic interactions. This feature of our work suggests that
anisotropy should be considered in future theoretical work aimed at the full
microscopic understanding of the emergence of the skyrmion state in this
material.


title:
Best dispersal strategies in spatially heterogeneous environments:
  optimization of the principal eigenvalue for indefinite fractional Neumann
  problems

abstract:
  We study the positive principal eigenvalue of a weighted problem associated
with the Neumann spectral fractional Laplacian. This analysis is related to the
investigation of the survival threshold in population dynamics. Our main result
concerns the optimization of such threshold with respect to the fractional
order $s\in(0,1]$, the case $s=1$ corresponding to the standard Neumann
Laplacian: when the habitat is not too fragmented, the principal positive
eigenvalue can not have local minima for $0<s<1$. As a consequence, the best
strategy for survival is either following the diffusion with $s=1$ (i.e.
Brownian diffusion), or with the lowest possible $s$ (i.e. diffusion allowing
long jumps), depending on the size of the domain. In addition, we show that
analogous results hold for the standard fractional Laplacian in $\mathbb{R}^N$,
in periodic environments.


title:
Lagrange-flux schemes: reformulating second-order accurate
  Lagrange-remap schemes for better node-based HPC performance

abstract:
  In a previous paper, we have achieved the performance analysis of staggered
Lagrange-remap schemes, a class of solvers widely used for Hydrodynamics
applications. This paper is devoted to the rethinking and redesign of the
Lagrange-remap process for achieving better performance using today's computing
architectures. As an unintended outcome, the analysis has lead us to the
discovery of a new family of solvers -- the so-called Lagrange-flux schemes --
that appear to be promising for the CFD community.


title: Rates of mixing for nonMarkov infinite measure semiflows

abstract:
  We develop an abstract framework for obtaining optimal rates of mixing and
higher order asymptotics for infinite measure semiflows. Previously, such
results were restricted to the situation where there is a first return
Poincar\'e map that is uniformly expanding and Markov. As illustrations of the
method, we consider semiflows over nonMarkov Pomeau-Manneville intermittent
maps with infinite measure, and we also obtain mixing rates for semiflows over
Collet-Eckmann maps with nonintegrable roof function.


title:
Signal Recovery in Uncorrelated and Correlated Dictionaries Using
  Orthogonal Least Squares

abstract:
  Though the method of least squares has been used for a long time in solving
signal processing problems, in the recent field of sparse recovery from
compressed measurements, this method has not been given much attention. In this
paper we show that a method in the least squares family, known in the
literature as Orthogonal Least Squares (OLS), adapted for compressed recovery
problems, has competitive recovery performance and computation complexity, that
makes it a suitable alternative to popular greedy methods like Orthogonal
Matching Pursuit (OMP). We show that with a slight modification, OLS can
exactly recover a $K$-sparse signal, embedded in an $N$ dimensional space
($K<<N$) in $M=\mathcal{O}(K\log (N/K))$ no of measurements with Gaussian
dictionaries. We also show that OLS can be easily implemented in such a way
that it requires $\mathcal{O}(KMN)$ no of floating point operations similar to
that of OMP. In this paper performance of OLS is also studied with sensing
matrices with correlated dictionary, in which algorithms like OMP does not
exhibit good recovery performance. We study the recovery performance of OLS in
a specific dictionary called \emph{generalized hybrid dictionary}, which is
shown to be a correlated dictionary, and show numerically that OLS has is far
superior to OMP in these kind of dictionaries in terms of recovery performance.
Finally we provide analytical justifications that corroborate the findings in
the numerical illustrations.


title: Borcherds products with prescribed divisor

abstract:
  Given an infinite set of special divisors satisfying a mild regularity
condition, we prove the existence of a Borcherds product of non-zero weight
whose divisor is supported on these special divisors. We also show that every
meromorphic Borcherds product is the quotient of two holomorphic ones. The
proofs of both results rely on the properties of vector valued Eisenstein
series for the Weil representation.


title:
On Witten Laplacians and Brascamp-Lieb's inequality on manifolds with
  boundary

abstract:
  In this paper, we derive from the supersymmetry of the Witten Laplacian
Brascamp-Lieb's type inequalities for general differential forms on compact
Riemannian manifolds with boundary. In addition to the supersymmetry, our
results essentially follow from suitable decompositions of the quadratic forms
associated with the Neumann and Dirichlet self-adjoint realizations of the
Witten Laplacian. They moreover imply the usual Brascamp-Lieb's inequality and
its generalization to compact Riemannian manifolds without boundary.


title: Electro-Mechanical Transition in Quantum dots

abstract:
  The strong coupling between electronic transport in a single-level quantum
dot and a capacitively coupled nano-mechanical oscillator may lead to a
transition towards a mechanically-bistable and blocked-current state. Its
observation is at reach in carbon-nanotube state-of-art experiments. In a
recent publication [Phys. Rev. Lett. 115, 206802 (2015)] we have shown that
this transition is characterized by pronounced signatures on the oscillator
mechanical properties: the susceptibility, the displacement fluctuation
spectrum and the ring-down time. These properties are extracted from transport
measurements, however the relation between the mechanical quantities and the
electronic signal is not always straightforward. Moreover the dependence of the
same quantities on temperature, bias or gate voltage, and external dissipation
has not been studied. The purpose of this paper is to fill this gap and provide
a detailed description of the transition. Specifically we find: (i) The
relation between the current-noise and the displacement spectrum. (ii) The
peculiar behavior of the gate-voltage dependence of these spectra at the
transition. (iii) The robustness of the transition towards the effect of
external fluctuations and dissipation.


title:
Dimension reduction techniques for the minimization of theta functions
  on lattices

abstract:
  We consider the minimization of theta functions
$\theta\_\Lambda(\alpha)=\sum\_{p\in\Lambda}e^{-\pi\alpha|p|^2}$ amongst
lattices $\Lambda\subset \mathbb R^d$, by reducing the dimension of the
problem, following as a motivation the case $d=3$, where minimizers are
supposed to be either the BCC or the FCC lattices. A first way to reduce
dimension is by considering layered lattices, and minimize either among
competitors presenting different sequences of repetitions of the layers, or
among competitors presenting different shifts of the layers with respect to
each other. The second case presents the problem of minimizing theta functions
also on translated lattices, namely minimizing $(L,u)\mapsto
\theta\_{L+u}(\alpha)$. Another way to reduce dimension is by considering
lattices with a product structure or by successively minimizing over concentric
layers. The first direction leads to the question of minimization amongst
orthorhombic lattices, whereas the second is relevant for asymptotics
questions, which we study in detail in two dimensions.


title: Stochastic invariance of closed sets with non-Lipschitz coefficients

abstract:
  This paper provides a new characterization of the stochastic invariance of a
closed subset of R^d with respect to a diffusion. We extend the well-known
inward pointing Stratonovich drift condition to the case where the diffusion
matrix can fail to be differentiable: we only assume that the covariance matrix
is. In particular, our result can be directly applied to construct affine
diffusions and polynomial preserving diffusions on any arbitrary closed set.


title: $L^$p Estimates For Degenerate Non-Local Kolmogorov Operators

abstract:
  Let $z = (x,y) \in {\mathbb R}^d \times {\mathbb R}^{N-d}$, with $1 \le d <
N$. We prove a priori estimates of the following type :$$\|\Delta\_{x}^{\frac
\alpha 2} v \|\_{L^p({\mathbb R}^N)} \lec\_p\Big \| L\_{x } v +
\sum\_{i,j=1}^{N}a\_{ij}z\_{i}\partial\_{z\_{j}} v \Big \|\_{L^p({\mathbb
R}^N)}, \;\; 1<p<\infty,$$for $v \in C\_0^{\infty}({\mathbb R}^N)$,where $L\_x$
is a non-local operator comparable with the ${\mathbb R}^d $-fractional
Laplacian $\Delta\_{x}^{\frac \alpha 2}$ in terms of symbols, $\alpha \in
(0,2)$. We require that when $L\_x$ is replaced by the classical ${\mathbb
R}^d$-Laplacian $\Delta\_{x}$, i.e., in the limit local case $\alpha =2$, the
operator$ \Delta\_{x} + \sum\_{i,j=1}^{N}a\_{ij}z\_{i}\partial\_{z\_{j}} $
satisfy a weak type H\"ormander condition with invariance by suitable
dilations. {Such} estimates were only known for $\alpha =2$. This is one of the
first results on $L^p $ estimates for degenerate non-local operators under
H\"ormander type conditions. We complete our result on $L^p$-regularity for $
L\_{x } + \sum\_{i,j=1}^{N}a\_{ij}z\_{i}\partial\_{z\_{j}} $ by proving
estimates like\begin{equation*} \|\Delta\_{y\_i}^{\frac {\alpha\_i} {2}} v
\|\_{L^p({\mathbb R}^N)} \lec\_p \Big \| L\_{x } v +
\sum\_{i,j=1}^{N}a\_{ij}z\_{i}\partial\_{z\_{j}} v \Big \|\_{L^p({\mathbb
R}^N)},\end{equation*}involving fractional Laplacians in the degenerate
directions $y\_i$ (here $\alpha\_i \in (0, { {1\wedge \alpha}})$ depends on
$\alpha $ and on the numbers of commutators needed to obtain the
$y\_i$-direction). The last estimates are new even in the local limit case
$\alpha =2$ which is also considered.


title: In-Out Formalism for One-Loop Effective Actions in QED and Gravity

abstract:
  The in-out formalism is a systematic and powerful method for finding the
effective actions in an electromagnetic field and a curved spacetime provided
that the field equation has explicitly known solutions. The effective action
becomes complex when pairs of charged particles are produced due to an electric
field and curved spacetime. This may lead to a conjecture of one-to-one
correspondence between the vacuum polarization (real part) and the vacuum
persistence (imaginary part). We illustrate the one-loop effective action in a
constant electric field in a Minkowski spacetime and in a uniform electric
field in a two-dimensional (anti-) de sitter space.


title:
TopicResponse: A Marriage of Topic Modelling and Rasch Modelling for
  Automatic Measurement in MOOCs

abstract:
  This paper explores the suitability of using automatically discovered topics
from MOOC discussion forums for modelling students' academic abilities. The
Rasch model from psychometrics is a popular generative probabilistic model that
relates latent student skill, latent item difficulty, and observed student-item
responses within a principled, unified framework. According to scholarly
educational theory, discovered topics can be regarded as appropriate
measurement items if (1) students' participation across the discovered topics
is well fit by the Rasch model, and if (2) the topics are interpretable to
subject-matter experts as being educationally meaningful. Such Rasch-scaled
topics, with associated difficulty levels, could be of potential benefit to
curriculum refinement, student assessment and personalised feedback. The
technical challenge that remains, is to discover meaningful topics that
simultaneously achieve good statistical fit with the Rasch model. To address
this challenge, we combine the Rasch model with non-negative matrix
factorisation based topic modelling, jointly fitting both models. We
demonstrate the suitability of our approach with quantitative experiments on
data from three Coursera MOOCs, and with qualitative survey results on topic
interpretability on a Discrete Optimisation MOOC.


title: Weyl law for the volume spectrum

abstract:
  Given $M$ a Riemannian manifold with (possibly empty) boundary, we show that
its volume spectrum $\{\omega_p(M)\}_{p\in\mathbb{N}}$ satisfies a Weyl law
that was conjectured by Gromov.


title:
Time-dependent analysis of an $M/M/c$ preemptive priority system with
  two priority classes

abstract:
  We analyze the time-dependent behavior of an $M/M/c$ priority queue having
two customer classes, class-dependent service rates, and preemptive priority
between classes. More particularly, we develop a method that determines the
Laplace transforms of the transition functions when the system is initially
empty. The Laplace transforms corresponding to states with at least $c$
high-priority customers are expressed explicitly in terms of the Laplace
transforms corresponding to states with at most $c - 1$ high-priority
customers. We then show how to compute the remaining Laplace transforms
recursively, by making use of a variant of Ramaswami's formula from the theory
of $M/G/1$-type Markov processes. While the primary focus of our work is on
deriving Laplace transforms of transition functions, analogous results can be
derived for the stationary distribution: these results seem to yield the most
explicit expressions known to date.


title:
Cognitive Science in the era of Artificial Intelligence: A roadmap for
  reverse-engineering the infant language-learner

abstract:
  During their first years of life, infants learn the language(s) of their
environment at an amazing speed despite large cross cultural variations in
amount and complexity of the available language input. Understanding this
simple fact still escapes current cognitive and linguistic theories. Recently,
spectacular progress in the engineering science, notably, machine learning and
wearable technology, offer the promise of revolutionizing the study of
cognitive development. Machine learning offers powerful learning algorithms
that can achieve human-like performance on many linguistic tasks. Wearable
sensors can capture vast amounts of data, which enable the reconstruction of
the sensory experience of infants in their natural environment. The project of
'reverse engineering' language development, i.e., of building an effective
system that mimics infant's achievements appears therefore to be within reach.
Here, we analyze the conditions under which such a project can contribute to
our scientific understanding of early language development. We argue that
instead of defining a sub-problem or simplifying the data, computational models
should address the full complexity of the learning situation, and take as input
the raw sensory signals available to infants. This implies that (1) accessible
but privacy-preserving repositories of home data be setup and widely shared,
and (2) models be evaluated at different linguistic levels through a benchmark
of psycholinguist tests that can be passed by machines and humans alike, (3)
linguistically and psychologically plausible learning architectures be scaled
up to real data using probabilistic/optimization principles from machine
learning. We discuss the feasibility of this approach and present preliminary
results.


title:
Twisted spin vortices in a spinor-dipolar Bose-Einstein condensate with
  Rashba spin-orbit coupling

abstract:
  We consider a spin-1 Bose-Einstein condensate with Rashba spin-orbit coupling
and dipole-dipole interaction confined in a cigar-shaped trap. Due to the
combined effects of spin-orbit coupling, dipole-dipole interaction, and trap
geometry, the system exhibits a rich variety of ground-state spin structures,
including twisted spin vortices. The ground-state phase diagram is determined
with respect to the strengths of the spin-orbit coupling and dipole-dipole
interaction.


title: Cseq2seq: Cyclic Sequence-to-Sequence Learning

abstract:
  The vanilla sequence-to-sequence learning (seq2seq) reads and encodes a
source sequence into a fixed-length vector only once, suffering from its
insufficiency in modeling structural correspondence between the source and
target sequence. Instead of handling this insufficiency with a linearly
weighted attention mechanism, in this paper, we propose to use a recurrent
neural network (RNN) as an alternative (Cseq2seq-I). During decoding,
Cseq2seq-I cyclically feeds the previous decoding state back to the encoder as
the initial state of the RNN, and reencodes source representations to produce
context vectors. We surprisingly find that the introduced RNN succeeds in
dynamically detecting translationrelated source tokens according to the partial
target sequence. Based on this finding, we further hypothesize that the partial
target sequence can act as a feedback to improve the understanding of the
source sequence. To test this hypothesis, we propose cyclic
sequence-to-sequence learning (Cseq2seq-II) which differs from the seq2seq only
in the reintroduction of previous decoding state into the same encoder. We
further perform parameter sharing on Cseq2seq-II to reduce parameter redundancy
and enhance regularization. In particular, we share the weights of the encoder
and decoder, and two targetside word embeddings, making Cseq2seq-II equivalent
to a single conditional RNN model, with 31% parameters pruned but even better
performance. Cseq2seq-II not only preserves the simplicity of seq2seq but also
yields comparable and promising results on machine translation tasks.
Experiments on Chinese- English and English-German translation show that
Cseq2seq achieves significant and consistent improvements over seq2seq and is
as competitive as the attention-based seq2seq model.


title:
Statistical and hydrodynamic properties of topological polymers for
  various graphs showing enhanced short-range correlation

abstract:
  For various polymers with different topological structures we numerically
evaluate the mean-square radius of gyration and the hydrodynamic radius
systematically through simulation. We call polymers with nontrivial topology
topological polymers. We evaluate the two quantities both for ideal and real
chain models and show that the ratios of the quantities among different
topological types do not depend on the existence of excluded volume if the
topological polymers have only up to trivalent vertices, as far as the polymers
investigated. We also evaluate the ratio of the gyration radius to the
hydrodynamic radius, which we expect to be universal from the viewpoint of
renormalization group. Furthermore, we show that the short-distance intrachain
correlation is much enhanced for topological polymers expressed with complex
graphs.


title:
Renormalization group equation improved analysis of $B \to \pi$ form
  factors from Light-Cone Sum Rules

abstract:
  Within the framework of $B$-meson light-cone sum rules, we compute the
one-loop level QCD corrections to $B\to \pi$ transition form factors at small $
q^{2}$ region, in implement of a complete renormalization group equation
evolution. To solve the renormalization group equations, we work at the "dual"
space where the anomalous dimensions of the jet function and the light-cone
distribution amplitudes are diagonal. With the complete renormalization group
equation evolution, the form factors are almost independent of the
factorization scale, which is shown numerically. We also extrapolate the
results of the form factors to the whole $q^2$ region, and compare their
behavior with other studies.


title: Optimal Design of Fractured Media with Prescribed Macroscopic Strain

abstract:
  In this work we consider an optimal design problem for two-component
fractured media for which a macroscopic strain is prescribed. Within the
framework of structured deformations, we derive an integral representation for
the relaxed energy functional. We start from an energy functional accounting
for bulk and surface contributions coming from both constituents of the
material; the relaxed energy densities, obtained via a blow-up method, are
determined by a delicate interplay between the optimization of sharp interfaces
and the diffusion of microcracks. This model has the far-reaching perspective
to incorporate elements of plasticity in optimal design of composite media.


title:
Multi-contact Walking Pattern Generation based on Model Preview Control
  of 3D COM Accelerations

abstract:
  We present a multi-contact walking pattern generator based on preview-control
of the 3D acceleration of the center of mass (COM). A key point in the design
of our algorithm is the calculation of contact-stability constraints. Thanks to
a mathematical observation on the algebraic nature of the frictional wrench
cone, we show that the 3D volume of feasible COM accelerations is a always a
downward-pointing cone. We reduce its computation to a convex hull of (dual) 2D
points, for which optimal O(n log n) algorithms are readily available. This
reformulation brings a significant speedup compared to previous methods, which
allows us to compute time-varying contact-stability criteria fast enough for
the control loop. Next, we propose a conservative trajectory-wide
contact-stability criterion, which can be derived from COM-acceleration volumes
at marginal cost and directly applied in a model-predictive controller. We
finally implement this pipeline and exemplify it with the HRP-4 humanoid model
in multi-contact dynamically walking scenarios.


title:
Multi-output microwave single-photon source using superconducting
  circuits with longitudinal and transverse couplings

abstract:
  Single-photon devices at microwave frequencies are important for applications
in quantum information processing and communication in the microwave regime. In
this work, we describe a proposal of a multi-output single-photon device. We
consider two superconducting resonators coupled to a gap-tunable qubit via both
its longitudinal and transverse degrees of freedom. Thus, this qubit-resonator
coupling differs from the coupling in standard circuit quantum-electrodynamic
systems described by the Jaynes-Cummings model. We demonstrate that an
effective quadratic coupling between one of the normal modes and the qubit can
be induced, and this induced second-order nonlinearity is much larger than that
for conventional Kerr-type systems exhibiting photon blockade. Assuming that a
coupled normal mode is resonantly driven, we observe that the output fields
from the resonators exhibit strong sub-Poissonian photon-number statistics and
photon antibunching. Contrary to previous studies on resonant photon blockade,
the first-excited state of our device is a pure single-photon Fock state rather
than a polariton state, i.e., a highly hybridized qubit-photon state. In
addition, it is found that the optical state truncation caused by the strong
qubit-induced nonlinearity can lead to an entanglement between the two
resonators, even in their steady state under the Markov approximation.


title: Leader election using random walks

abstract:
  In the classical leader election procedure all players toss coins
independently and those who get tails leave the game, while those who get heads
move to the next round where the procedure is repeated. We investigate a
generalizion of this procedure in which the labels (positions) of the players
who remain in the game are determined using an integer-valued random walk. We
study the asymptotics of some relevant quantities for this model such as: the
positions of the persons who remained after $n$ rounds; the total number of
rounds until all the persons among $1,2,\ldots,M$ leave the game; and the
number of players among $1,2,\ldots,M$ who survived the first $n$ rounds. Our
results lead to some interesting connection with Galton-Watson branching
processes and with the solutions of certain stochastic-fixed point equations
arising in the context of the stability of point processes under thinning. We
describe the set of solutions to these equations and thus provide a
characterization of one-dimensional point processes that are stable with
respect to thinning by integer-valued random walks.


title: Mapping curved spacetimes into Dirac spinors

abstract:
  We show how to transform a Dirac equation in curved spacetime into a Dirac
equation in flat spacetime. In particular, we show that any solution of the
free massless Dirac equation in a 1+1 dimensional flat spacetime can be
transformed via a local phase transformation into a solution of the
corresponding Dirac equation in a curved background, where the spacetime metric
is encoded into the phase. In this way, the existing quantum simulators of the
Dirac equation can naturally incorporate curved spacetimes. As a first example
we use our technique to obtain solutions of the Dirac equation in a particular
family of interesting spacetimes in 1+1 dimensions.


title:
The ALMA Protostellar Interferometric Line Survey (PILS): First results
  from an unbiased submillimeter wavelength line survey of the Class 0
  protostellar binary IRAS 16293-2422 with ALMA

abstract:
  The inner regions of the envelopes surrounding young protostars are
characterised by a complex chemistry, with prebiotic molecules present on the
scales where protoplanetary disks eventually may form. This paper introduces a
systematic survey, "Protostellar Interferometric Line Survey (PILS)" of the
Class 0 protostellar binary IRAS 16293-2422 using the Atacama Large
Millimeter/submillimeter Array (ALMA). The survey covers the full frequency
range from 329 to 363 GHz (0.8 mm) with additional targeted observations at 3.0
and 1.3 mm. More than 10,000 features are detected toward one component in the
protostellar binary. Glycolaldehyde, its isomers, methyl formate and acetic
acid, and its reduced alcohol, ethylene glycol, are clearly detected. For
ethylene glycol both lowest state conformers, aGg' and gGg', are detected, the
latter for the first time in the ISM. The abundance of glycolaldehyde is
comparable to or slightly larger than that of ethylene glycol. In comparison to
the Galactic Center, these two species are over-abundant relative to methanol,
possibly an indication of formation at low temperatures in CO-rich ices. Both
13C and deuterated isotopologues of glycolaldehyde are detected, also for the
first time ever in the ISM. For the deuterated species, a D/H ratio of
approximately 5% is found with no differences between the deuteration in the
different functional groups of glycolaldehyde. Measurements of the 13C-species
lead to a 12C:13C ratio of approximately 30, lower than the typical ISM value.
This low ratio may reflect an enhancement of 13CO in the ice due to either
ion-molecule reactions in the gas before freeze-out or differences in the
temperatures where 12CO and 13CO ices sublimate. The results reinforce the
importance of low-temperature grain surface chemistry for the formation of
prebiotic molecules seen here in the gas after sublimation of the entire ice
mantle.


title: Dislocation climb models from atomistic scheme to dislocation dynamics

abstract:
  We develop a mesoscopic dislocation dynamics model for vacancy-assisted
dislocation climb by upscalings from a stochastic model on the atomistic scale.
Our models incorporate microscopic mechanisms of (i) bulk diffusion of
vacancies, (ii) vacancy exchange dynamics between bulk and dislocation core,
(iii) vacancy pipe diffusion along the dislocation core, and (iv) vacancy
attachment-detachment kinetics at jogs leading to the motion of jogs. Our
mesoscopic model consists of the vacancy bulk diffusion equation and a
dislocation climb velocity formula. The effects of pipe diffusion and the jog
structure on dislocations are incorporated by a Robin boundary condition near
the dislocations for the bulk diffusion equation and a new contribution in the
dislocation climb velocity due to vacancy pipe diffusion driven by the stress
variation along the dislocation. Our climb formulation is able to
quantitatively describe the translation of prismatic loops at low temperatures
when the bulk diffusion is negligible. Using this new formulation, we derive
analytical formulas for the climb velocity of a straight edge dislocation and a
prismatic circular loop. Our dislocation climb formulation can be implemented
in dislocation dynamics simulations to incorporate all the above four
microscopic mechanisms of dislocation climb.


title: Macroscopic limit of the Becker-D\"oring equation via gradient flows

abstract:
  This work considers gradient structures for the Becker-D\"oring equation and
its macroscopic limits. The result of Niethammer [17] is extended to prove the
convergence not only for solutions of the Becker-D\"oring equation towards the
Lifshitz-Slyozov-Wagner equation of coarsening, but also the convergence of the
associated gradient structures. We establish the gradient structure of the
nonlocal coarsening equation rigorously and show continuous dependence on the
initial data within this framework. Further, on the considered time scale the
small cluster distribution of the Becker--D\"oring equation follows a
quasistationary distribution dictated by the monomer concentration.


title:
Hydrodynamic description of (visco)elastic composite materials and
  relative strains as a new macroscopic variable

abstract:
  One possibility to adjust material properties to a specific need is to embed
units of one substance into a matrix of another substance. Even materials that
are readily tunable during operation can be generated in this way. In
(visco)elastic substances, both the matrix material as well as the inclusions
and/or their immediate environment can be dynamically deformed. If the typical
dynamic response time of the inclusions and their surroundings approach the
macroscopic response time, their deformation processes need to be included into
a dynamic macroscopic characterization. Along these lines, we present a
hydrodynamic description of (visco)elastic composite materials. For this
purpose, additional strain variables reflect the state of the inclusions and
their immediate environment. These additional strain variables in general are
not set by a coarse-grained macroscopic displacement field. Apart from that,
during our derivation, we also include the macroscopic variables of relative
translations and relative rotations that were previously introduced in
different contexts. As a central point, our approach reveals and classifies the
importance of a new macroscopic variable: relative strains. We analyze two
simplified minimal example geometries as an illustration.


title:
Two-Level Spatial Multiplexing using Hybrid Beamforming Antenna Arrays
  for mmWave Communications

abstract:
  In this work, we consider a two-level hierarchical MIMO antenna array system,
where each antenna of the upper level is made up of a subarray on the lower
one. The concept of spatial multiplexing is applied twice in this situation:
Firstly, the spatial multiplexing of a Line-of-Sight (LoS) MIMO system is
exploited. It is based on appropriate (sub-)array distances and achieves
multiplexing gain due to phase differences among the signals at the receive
(sub-)arrays. Secondly, one or more additional reflected paths of different
angles (separated from the LoS path by different spatial beams at the
subarrays) are used to exploit spatial multiplexing between paths.
  By exploiting the above two multiplexing kinds simultaneously, a high
dimensional system with maximum spatial multiplexing is proposed by jointly
using 'phase differences' within paths and 'angular differences' between paths.
The system includes an advanced hybrid beamforming architecture with large
subarray separation, which could occur in millimeter wave backhaul scenarios.
The possible gains of the system w.r.t. a pure LOS MIMO system are illustrated
by evaluating the capacities with total transmit power constraints.


title:
Spectroscopic characterisation of CARMENES target candidates from FEROS,
  CAFE and HRS high-resolution spectra

abstract:
  CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with
Near-infrared and optical Echelle Spectrographs) started a new planet survey on
M-dwarfs in January this year. The new high-resolution spectrographs are
operating in the visible and near-infrared at Calar Alto Observatory. They will
perform high-accuracy radial-velocity measurements (goal 1 m s-1) of about 300
M-dwarfs with the aim to detect low-mass planets within habitable zones. We
characterised the candidate sample for CARMENES and provide fundamental
parameters for these stars in order to constrain planetary properties and
understand star-planet systems. Using state-of-the-art model atmospheres
(PHOENIX-ACES) and chi2-minimization with a downhill-simplex method we
determine effective temperature, surface gravity and metallicity [Fe/H] for
high-resolution spectra of around 480 stars of spectral types M0.0-6.5V taken
with FEROS, CAFE and HRS. We find good agreement between the models and our
observed high-resolution spectra. We show the performance of the algorithm, as
well as results, parameter and spectral type distributions for the CARMENES
candidate sample, which is used to define the CARMENES target sample. We also
present first preliminary results obtained from CARMENES spectra.


title:
New ways to synthesize lead sulfide nanosheets - substituted alkanes
  direct the growth of 2D nanostructures

abstract:
  Two-dimensional colloidal nanosheets represent very attractive optoelectronic
materials. They combine good lateral conductivity with solution-processability
and geometry-tunable electronic properties. In case of PbS nanosheets, so far
the synthesis was driven by the addition of chloroalkanes as coligands. Here,
we demonstrate how to synthesize two-dimensional lead sulfide nanostructures
using other halogen alkanes and primary amines. Further, we show that at a
reaction temperature of 170C a coligand is not even necessary, and the only
ligand, oleic acid, controls the anisotropic growth of the two-dimensional
structures and using thiourea as sulfide source, nanosheets with lateral
dimensions of over 10 microns are possible.


title: Orbifold Milnor lattice and orbifold intersection form

abstract:
  For a germ of a quasihomogeneous function with an isolated critical point at
the origin invariant with respect to an appropriate action of a finite abelian
group, H. Fan, T. Jarvis, and Y. Ruan defined the so-called quantum cohomology
group. It is considered as the main object of the quantum singularity theory
(FJRW-theory). We define orbifold versions of the monodromy operator on the
quantum (co)homology group, of the Milnor lattice, of the Seifert form and of
the intersection form. We also describe some symmetry properties of invariants
of invertible polynomials refining the known ones.


title:
High-resolution mid-infrared spectroscopy of buffer-gas-cooled
  methyltrioxorhenium molecules

abstract:
  We demonstrate cryogenic buffer-gas cooling of gas-phase methyltrioxorhenium
(MTO). This molecule is closely related to chiral organometallic molecules
where the parity-violating energy differences between enantiomers may be
measurable. The molecules are produced with a rotational temperature of
approximately 6~K by laser ablation of an MTO pellet inside a cryogenic helium
buffer gas cell. Facilitated by the low temperature, we demonstrate absorption
spectroscopy of the 10.2~$\mu$m antisymmetric Re=O stretching mode of MTO with
a resolution of 8~MHz and a frequency accuracy of 30~MHz. We partially resolve
the hyperfine structure and measure the nuclear quadrupole coupling of the
excited vibrational state.


title: Fixed points of 321-avoiding permutations

abstract:
  We describe the distribution of the number and location of the fixed points
of permu- tations that avoid the pattern 321 via a bijection with rooted plane
trees on n + 1 vertices. Using the local limit theorem for Galton-Watson trees,
we are able to give an explicit description of the limit of this distribution.


title:
A penalized inference approach to stochastic block modelling of
  community structure in the Italian Parliament

abstract:
  We analyse bill cosponsorship networks in the Italian Chamber of Deputies. In
comparison with other parliaments, a distinguishing feature of the Chamber is
the large number of political groups. Our analysis aims to infer the pattern of
collaborations between these groups from data on bill cosponsorships. We
propose an extension of stochastic block models for edge-valued graphs and
derive measures of group productivity and of collaboration between political
parties. As the model proposed encloses a large number of parameters, we pursue
a penalized likelihood approach that enables us to infer a sparse reduced graph
displaying collaborations between political parties.


title:
High-momentum tails as magnetic structure probes for strongly-correlated
  $SU(\kappa)$ fermionic mixtures in one-dimensional traps

abstract:
  A universal $k^{-4}$ decay of the large-momentum tails of the momentum
distribution, fixed by Tan's contact coefficients, constitutes a direct
signature of strong correlations in a short-range interacting quantum gas. Here
we consider a repulsive multicomponent Fermi gas under harmonic confinement, as
in the experiment of Pagano et al. [Nat. Phys. {\bf 10}, 198 (2014)], realizing
a gas with tunable $SU(\kappa)$ symmetry. We exploit an exact solution at
infinite repulsion to show a direct correspondence between the value of the
Tan's contact for each of the $\kappa$ components of the gas and the Young
tableaux for the $S_N$ permutation symmetry group identifying the magnetic
structure of the ground-state. This opens a route for the experimental
determination of magnetic configurations in cold atomic gases, employing only
standard (spin-resolved) time-of-flight techniques. Combining the exact result
with matrix-product-states simulations, we obtain the Tan's contact at all
values of repulsive interactions. We show that a local density approximation
(LDA) on the Bethe-Ansatz equation of state for the homogeneous mixture is in
excellent agreement with the results for the harmonically confined gas. At
strong interactions, the LDA predicts a scaling behavior of the Tan's contact.
This provides a useful analytical expression for the dependence on the number
of fermions, number of components and on interaction strength. Moreover, using
a virial approach in the limit of infinite interactions, we show that the
contact increases with the temperature and the number of components. At zero
temperature, we predict that the weight of the momentum distribution tails
increases with interaction strength and the number of components if the
population per component is kept constant. This latter property was
experimentally observed in Ref.~[Nat. Phys. {\bf 10}, 198 (2014)].


title: Waring-Goldbach Problem with Piatetski-Shapiro Primes

abstract:
  In this paper, we exhibit an asymptotic formula for the number of
representations of a large integer as a sum of a fixed power of
Piatetski-Shapiro primes, thereby establishing a variant of Waring-Goldbach
problem with primes from a sparse sequence.


title: On the Green function and Poisson integrals of the Dunkl Laplacian

abstract:
  We prove the existence and study properties of the Green function of the unit
ball for the Dunkl Laplacian $\Delta_k$ in $\mathbb{R}^d$. As applications we
derive the Poisson-Jensen formula for $\Delta_k$-subharmonic functions and
Hardy-Stein identities for the Poisson integrals of $\Delta_k$. We also obtain
sharp estimates of the Newton potential kernel, Green function and Poisson
kernel in the rank one case in $\mathbb{R}^d$. These estimates contrast sharply
with the well-known results in the potential theory of the classical Laplacian.


title:
Total infrared luminosity estimation from local galaxies in AKARI all
  sky survey

abstract:
  We aim to use the a new and improved version of AKARI all sky survey
catalogue of far-infrared sources to recalibrate the formula to derive the
total infrared luminosity. We cross-match the faint source catalogue (FSC) of
IRAS with the new AKARI-FIS and obtained a sample of 2430 objects. Then we
calculate the total infrared (TIR) luminosity $L_{\textrm{TIR}}$ from the
Sanders at al. (1996) formula and compare it with total infrared luminosity
from AKARI FIS bands to obtain new coefficients for the general relation to
convert FIR luminosity from AKARI bands to the TIR luminosity.


title: Cyclic dominance in a two-person Rock-Scissors-Paper game

abstract:
  The Rock-Scissors-Paper game has been studied to account for cyclic behaviour
under various game dynamics. We use a two-person parametrised version of this
game. The cyclic behaviour is observed near a heteroclinic cycle, in a
heteroclinic network, with two nodes such that, at each node, players alternate
in winning and losing. This cycle is shown to be as stable as possible for a
wide range of parameter values. The parameters are related to the players'
payoff when a tie occurs.


title:
Simultaneous Water Vapor and Dry Air Optical Path Length Measurements
  and Compensation with the Large Binocular Telescope Interferometer

abstract:
  The Large Binocular Telescope Interferometer uses a near-infrared camera to
measure the optical path length variations between the two AO-corrected
apertures and provide high-angular resolution observations for all its science
channels (1.5-13 $\mu$m). There is however a wavelength dependent component to
the atmospheric turbulence, which can introduce optical path length errors when
observing at a wavelength different from that of the fringe sensing camera.
Water vapor in particular is highly dispersive and its effect must be taken
into account for high-precision infrared interferometric observations as
described previously for VLTI/MIDI or the Keck Interferometer Nuller. In this
paper, we describe the new sensing approach that has been developed at the LBT
to measure and monitor the optical path length fluctuations due to dry air and
water vapor separately. After reviewing the current performance of the system
for dry air seeing compensation, we present simultaneous H-, K-, and N-band
observations that illustrate the feasibility of our feedforward approach to
stabilize the path length fluctuations seen by the LBTI nuller.


title:
Large anomalous magnetic moment in three-dimensional Dirac and Weyl
  semimetals

abstract:
  We investigate the effect of Coulomb interactions on the electromagnetic
response of three-dimensional Dirac and Weyl semimetals. In a calculation
reminiscent of Schwinger's seminal work on quantum electrodynamics, we find
three physically distinct effects for the anomalous magnetic moment of the
relativisticlike quasiparticles in the semimetal. In the case of nonzero
doping, the anomalous magnetic moment is finite at long wavelengths and
typically orders of magnitude larger than Schwinger's result. We also find
interesting effects of one of the three new Hamiltonian terms on the
topological surface states at the interface between vacuum and a Weyl
semimetal. We conclude that observation of these effects should be within
experimental reach.


title:
Novel directed search strategy to detect continuous gravitational waves
  from neutron stars in low- and high-eccentricity binary systems

abstract:
  We describe a novel, very fast and robust, directed search incoherent method
for periodic gravitational waves (GWs) from neutron stars in binary systems. As
directed search, we assume the source sky position to be known with enough
accuracy, but all other parameters are supposed to be unknown. We exploit the
frequency-modulation due to source orbital motion to unveil the signal
signature by commencing from a collection of time and frequency peaks. We
validate our pipeline adding 131 artificial continuous GW signals from pulsars
in binary systems to simulated detector Gaussian noise, characterized by a
power spectral density Sh = 4x10^-24 Hz^-1/2 in the frequency interval [70,
200] Hz, which is overall commensurate with the advanced detector design
sensitivities. The pipeline detected 128 signals, and the weakest signal
injected and detected has a GW strain amplitude of ~10^-24, assuming one month
of gapless data collected by a single advanced detector. We also provide
sensitivity estimations, which show that, for a single- detector data covering
one month of observation time, depending on the source orbital Doppler
modulation, we can detect signals with an amplitude of ~7x10^-25. By using
three detectors, and one year of data, we would easily gain more than a factor
3 in sensitivity, translating into being able to detect weaker signals. We also
discuss the parameter estimate proficiency of our method, as well as
computational budget, which is extremely cheap. In fact, sifting one month of
single-detector data and 131 Hz-wide frequency range takes roughly 2.4 CPU
hours. Due to the high computational speed, the current procedure can be
readily applied in ally-sky schemes, sieving in parallel as many sky positions
as permitted by the available computational power.


title:
An investigation of nonclassical properties of light using an optical
  tomogram

abstract:
  By analyzing the optical tomogram of a linear superposition of coherent
states, we show that distinctive signatures of the macroscopic superposition
states are displayed directly in the optical tomograms of the states. We also
study the effect of decoherence on the optical tomograms of the macroscopic
superposition states. Since the wave packet fractional revivals are associated
with the generation of macroscopic superposition states, these signatures help
in visualizing the revivals and fractional revivals occurring in a nonlinear
medium directly in the optical tomogram of the time-evolved state. We found
that the optical tomogram of the time-evolved state at the instants of
fractional revivals show structures with sinusoidal strands. Using a class of
initial superposed wave packets evolving in the Kerr-like medium, we further
show that the condition for the occurrence of fractional revival phenomenon
depends on the number of wave packets composing the initial superposition
state. In the case of a two-mode electromagnetic field, we investigate the
entanglement of the state directly using the optical tomogram. We have shown
that the signatures of entanglement can be observed directly in the single-mode
optical tomogram of the state without reconstructing the density matrix of the
system. We also analyze the effect of decoherence on the optical tomograms of
the entangled states. Further, we examine the optical tomograms of the
entangled states generated using a beam splitter with a Kerr medium placed into
one of its input modes. We have found the signatures of entanglement in the
optical tomogram for the entangled states generated at the instants of two- and
three-subpacket fractional revival times.


title: Measurement - induced qudit geometric discord

abstract:
  We study the measurement-induced geometric discord based on the trace norm
and generalize some properties known for qutrits to qudits. Previous
preliminary results for bipartite qutrit systems (i.e. d=3 systems) are here
strictly proved for arbitrary d. Present study supports observations, coming
also from other approaches, that systems with $d \geq 3$ show similar behaviour
when quantum correlations are concerned, but there is pronounced difference
between d=2 and d=3. Qubit systems are exceptionally simple. Underlying
geometry of state spaces and related Lie groups are responsible for that.


title:
A flow based pruning scheme for enumerative equitable coloring
  algorithms

abstract:
  An equitable graph coloring is a proper vertex coloring of a graph G where
the sizes of the color classes differ by at most one. The equitable chromatic
number is the smallest number k such that G admits such equitable k-coloring.
We focus on enumerative algorithms for the computation of the equitable
coloring number and propose a general scheme to derive pruning rules for them:
We show how the extendability of a partial coloring into an equitable coloring
can be modeled via network flows. Thus, we obtain pruning rules which can be
checked via flow algorithms. Computational experiments show that the search
tree of enumerative algorithms can be significantly reduced in size by these
rules and, in most instances, such naive approach even yields a faster
algorithm. Moreover, the stability, i.e., the number of solved instances within
a given time limit, is greatly improved.
  Since the execution of flow algorithms at each node of a search tree is time
consuming, we derive arithmetic pruning rules (generalized Hall-conditions)
from the network model. Adding these rules to an enumerative algorithm yields
an even larger runtime improvement.


title:
Constraining early and interacting dark energy with gravitational wave
  standard sirens: the potential of the eLISA mission

abstract:
  We perform a forecast analysis of the capability of the eLISA space-based
interferometer to constrain models of early and interacting dark energy using
gravitational wave standard sirens. We employ simulated catalogues of standard
sirens given by merging massive black hole binaries visible by eLISA, with an
electromagnetic counterpart detectable by future telescopes. We consider
three-arms mission designs with arm length of 1, 2 and 5 million km, 5 years of
mission duration and the best-level low frequency noise as recently tested by
the LISA Pathfinder. Standard sirens with eLISA give access to an intermediate
range of redshift $1\lesssim z \lesssim 8$, and can therefore provide
competitive constraints on models where the onset of the deviation from
$\Lambda$CDM (i.e. the epoch when early dark energy starts to be
non-negligible, or when the interaction with dark matter begins) occurs
relatively late, at $z\lesssim 6$. If instead early or interacting dark energy
is relevant already in the pre-recombination era, current cosmological probes
(especially the cosmic microwave background) are more efficient than eLISA in
constraining these models, except possibly in the interacting dark energy model
if the energy exchange is proportional to the energy density of dark energy.


title: Data Filtering for Cluster Analysis by $\ell_0$-Norm Regularization

abstract:
  A data filtering method for cluster analysis is proposed, based on minimizing
a least squares function with a weighted $\ell_0$-norm penalty. To overcome the
discontinuity of the objective function, smooth non-convex functions are
employed to approximate the $\ell_0$-norm. The convergence of the global
minimum points of the approximating problems towards global minimum points of
the original problem is stated. The proposed method also exploits a suitable
technique to choose the penalty parameter. Numerical results on synthetic and
real data sets are finally provided, showing how some existing clustering
methods can take advantages from the proposed filtering strategy.


title: How walls affect the dynamics of self-phoretic microswimmers

abstract:
  We study the effect of a nearby planar wall on the propulsion of a spherical
phoretic micro-swimmer driven by reactions on its surface. An asymmetric
coverage of catalysts on its surface which absorb reactants and generate
products gives rise to an anisotropic interfacial flow that propels the
swimmer. We analyse the near-wall dynamics of such a self-phoretic swimmer as a
function of the asymmetric catalytic coverage of the surface. By an analysis of
the fundamental singularities of the flow and concentration or electrostatic
potential gradients generated we are able to obtain and rationalise a phase
diagram of behaviours as a function of the characteristics of the swimmer
surface. We find a variety of possible behaviours, from "bound states" where
the swimmer remains near the wall to "scattering" or repulsive trajectories in
which the swimmer ends far from the wall. The formation of some of the bound
states is a purely wall-phoretic effect and cannot be obtained by simply
mapping a phoretic swimmer to a hydrodynamic one.


title: Relations in the tautological ring of the moduli space of K3 surfaces

abstract:
  We study the interplay of the moduli of curves and the moduli of K3 surfaces
via the virtual class of the moduli spaces of stable maps. Using Getzler's
relation in genus 1, we construct a universal decomposition of the diagonal in
Chow in the third fiber product of the universal K3 surface. The decomposition
has terms supported on Noether-Lefschetz loci which are not visible in the
Beauville-Voisin decomposition for a fixed K3 surface. As a result of our
universal decomposition, we prove the conjecture of Marian-Oprea-Pandharipande:
the full tautological ring of the moduli space of K3 surfaces is generated in
Chow by the classes of the Noether-Lefschetz loci. Explicit boundary relations
are constructed for all kappa classes.
  More generally, we propose a connection between relations in the tautological
ring of the moduli spaces of curves and relations in the tautological ring of
the moduli space of K3 surfaces. The WDVV relation in genus 0 is used in our
proof of the MOP conjecture.


title:
The magnetic susceptibility of YBa$_{2}$Cu$_{3}$O$_{6+x}$ crystals:
  unusual Curie behavior and small contributions from charge density waves

abstract:
  We report measurements of the magnetic susceptibility of twinned single
crystals of YBa$_{2}$Cu$_{3}$O$_{6+x}$ from just above their superconducting
transition temperatures to 300 K with magnetic fields of up to 5 T applied
parallel and perpendicular to the CuO$_2$ planes at 7 values of $x$.
Appropriate analysis allows the relatively small, but still important, Curie
terms to be separated from other contributions to the susceptibility. Our data
support a picture in which the Curie terms arise from oxygen disorder in the
Cu-O chains. This agrees with published work on polycrystalline samples where
the sample cooling rate was varied, but here we show that the Curie plots
flatten out above 200 K. We identify small effects of charge density wave (CDW)
instabilities in the temperature ($T$) derivative of the in-plane
susceptibility $d\chi_{ab}(T)/dT$ and discuss their $x$-dependence. For
$x=$0.67 we make a detailed comparison with published high energy X-ray
diffraction data using a minimal model involving Fermi arcs, thereby obtaining
values for the CDW energy gap and the Helmholtz free energy in a coherence
volume. At 80 and 100 K the latter is comparable with, or smaller than $k_BT$
respectively, highlighting the probable importance of thermal fluctuations. We
note that the effect of the Lorentz force on charge carriers in the Fermi arcs
could provide a simple mechanism for enhancing the CDWs in high magnetic
fields, as suggested by recent experiments.


title:
Dispersive hydrodynamics of nonlinear polarization waves in
  two-component Bose-Einstein condensates

abstract:
  We study one dimensional mixtures of two-component Bose-Einstein condensates
in the limit where the intra-species and inter-species interaction constants
are very close. Near the mixing-demixing transition the polarization and the
density dynamics decouple. We study the nonlinear polarization waves, show that
they obey a universal (i.e., parameter free) dynamical description, identify a
new type of algebraic soliton, explicitly write simple wave solutions, and
study the Gurevich-Pitaevskii problem in this context.


title: Tidal bridge and tidal dwarf candidates in the interacting system Arp194

abstract:
  Arp194 is a system of recently collided galaxies, where the southern galaxy
(S) passed through the gaseous disc of the northern galaxy (N) which in turn
consists of two close components. This system is of special interest due to the
presence of regions of active star-formation in the bridge between galaxies,
the brightest of which (the region A) has a size of at least 4 kpc. We obtained
three spectral slices of the system for different slit positions at the 6-m
telescope of SAO RAS. We estimated the radial distribution of line-of-sight
velocity and velocity dispersion as well as the intensities of emission lines
and oxygen abundance $12+\log(\mathrm{O/H})$. The gas in the bridge is only
partially mixed chemically and spatially: we observe the O/H gradient with the
galactocentric distances both from S and N galaxies and a high dispersion of
O/H in the outskirts of N-galaxy. Velocity dispersion of the emission-line gas
is the lowest in the star-forming sites of the bridge and exceeds 50-70 km/s in
the disturbed region of N-galaxy. Based on the SDSS photometrical data and our
kinematical profiles we measured the masses of stellar population and the
dynamical masses of individual objects. We confirm that the region A is the
gravitationally bound tidal dwarf with the age of $10^7 - 10^8 $ yr, which is
falling onto the parent S- galaxy. There is no evidence of the significant
amount of dark matter in this dwarf galaxy.


title: Dynamical behavior of microgels of Interpenetrated Polymer Networks

abstract:
  Microgel suspensions of Interpenetrated Polymer Network (IPN) of PNIPAM and
PAAc in D$_2$O, have been investigated through dynamic light scattering as a
function of temperature, pH and concentration across the Volume Phase
Transition (VPT). The dynamics of the system is slowed down under H/D isotopic
substitution due to the different balance between polymer/polymer and
polymer/solvent interactions suggesting the crucial role played by H-bondings.
The swelling behavior, reduced with respect to PNIPAM and water, has been
described by the Flory-Rehner theory, tested for PNIPAM microgel and
successfully expanded to higher order for IPN microgels. Moreover the
concentration dependence of the relaxation time at neutral pH has highlighted
two different routes to approach the glass transition: Arrhenius and
super-Arrhenius (Vogel Fulcher Tammann) respectively below and above the VPT
and a fragility plot has been derived. Fragility can be tuned by changing
temperature: across the VPT particles undergo a transition from soft-strong to
stiff-fragile.


title: Lattice-Boltzmann Simulations of Microswimmer-Tracer Interactions

abstract:
  Hydrodynamic interactions in systems comprised of self-propelled particles,
such as swimming microorganisms, and passive tracers have a significant impact
on the tracer dynamics compared to the equivalent "dry" sample. However, such
interactions are often difficult to take into account in simulations due to
their computational cost. Here, we perform a systematic investigation of
swimmer-tracer interaction using an efficient force/counter-force based
lattice-Boltzmann (LB) algorithm [J. de Graaf~\textit{et al.}, J. Chem.
Phys.~\textbf{144}, 134106 (2016)] in order to validate its ability to capture
the relevant low-Reynolds-number physics. We show that the LB algorithm
reproduces far-field theoretical results well, both in a system with periodic
boundary conditions and in a spherical cavity with no-slip walls, for which we
derive expressions here. The force-lattice coupling of the LB algorithm leads
to a "smearing out" of the flow field, which strongly perturbs the tracer
trajectories at close swimmer-tracer separations, and we analyze how this
effect can be accurately captured using a simple renormalized hydrodynamic
theory. Finally, we show that care must be taken when using LB algorithms to
simulate systems of self-propelled particles, since its finite momentum
transport time can lead to significant deviations from theoretical predictions
based on Stokes flow. These insights should prove relevant to the future study
of large-scale microswimmer suspensions using these methods.

categories: physics.flu-dyn cond-mat.soft cond-mat.stat-mech physics.bio-ph


title:
SwiDeN : Convolutional Neural Networks For Depiction Invariant Object
  Recognition

abstract:
  Current state of the art object recognition architectures achieve impressive
performance but are typically specialized for a single depictive style (e.g.
photos only, sketches only). In this paper, we present SwiDeN : our
Convolutional Neural Network (CNN) architecture which recognizes objects
regardless of how they are visually depicted (line drawing, realistic shaded
drawing, photograph etc.). In SwiDeN, we utilize a novel `deep' depictive
style-based switching mechanism which appropriately addresses the
depiction-specific and depiction-invariant aspects of the problem. We compare
SwiDeN with alternative architectures and prior work on a 50-category Photo-Art
dataset containing objects depicted in multiple styles. Experimental results
show that SwiDeN outperforms other approaches for the depiction-invariant
object recognition problem.


title:
Directional detection of Dark Matter with the MIcro-tpc MAtrix of
  Chambers

abstract:
  Particles weakly interacting with ordinary matter, with an associated mass of
the order of an atomic nucleus (WIMPs), are plausible candidates for Dark
Matter. The direct detection of an elastic collision of a target nuclei induced
by one of these WIMPs has to be discriminated from the signal produced by the
neutrons, which leaves the same signal in a detector. The MIMAC (MIcro-tpc
MAtrix of Chambers) collaboration has developed an original prototype detector
which combines a large pixelated Micromegas coupled with a fast,
self-triggering, electronics. Aspects of the two-chamber module in operation in
the Modane Underground Laboratory are presented: calibration, characterization
of the $^{222}$Rn progeny. A new test bench combining a MIMAC chamber with the
COMIMAC portable quenching line has been set up to characterize the 3D tracks
of low energy ions in the MIMAC gas mixture: the preliminary results thereof
are presented. Future steps are briefly discussed.


title:
Hole probabilities for determinantal point processes in the complex
  plane

abstract:
  We study the hole probabilities for ${\mathcal X}_{\infty}^{(\alpha)}$
($\alpha>0$), a determinantal point process in the complex plane with the
kernel $\mathbb
K_{\infty}^{(\alpha)}(z,w)=\frac{\alpha}{2\pi}E_{\frac{2}{\alpha},\frac{2}{\alpha}}(z\bar
w)e^{-\frac{|z|^{\alpha}}{2}-\frac{|w|^{\alpha}}{2}}$ with respect to Lebesgue
measure on the complex plane, where $E_{a,b}(z)$ denotes the Mittag-Leffler
function. Let $U$ be an open subset of
$D(0,(\frac{2}{\alpha})^{\frac{1}{\alpha}})$ and ${\mathcal
X}_{\infty}^{(\alpha)}(rU)$ denote the number of points of ${\mathcal
X}_{\infty}^{(\alpha)}$ that fall in $rU$. Then, under some conditions on $U$,
we show that $$ \lim_{r\to \infty}\frac{1}{r^{2\alpha}}\log\mathbb P[\mathcal
X_{\infty}^{(\alpha)}(rU)=0]=R_{\emptyset}^{(\alpha)}-R_{U}^{(\alpha)}, $$
where $\emptyset$ is the empty set and $$ R_U^{(\alpha)}:=\inf_{\mu\in \mathcal
P(U^c)}\left\{\iint \log{\frac{1}{|z-w|}}d\mu(z)d\mu(w)+\int
|z|^{\alpha}d\mu(z) \right\}, $$ $\mathcal P(U^c)$ is the space of all
compactly supported probability measures with support in $U^c$. Using potential
theory, we give an explicit formula for $R_U^{(\alpha)}$, the minimum possible
energy of a probability measure compactly supported on $U^c$ under logarithmic
potential with an external field $\frac{|z|^{\alpha}}{2}$. In particular,
$\alpha=2$ gives the hole probabilities for the infinite ginibre ensemble.
Moreover, we calculate $R_U^{(2)}$ explicitly for some special sets like
annulus, cardioid, ellipse, equilateral triangle and half disk.


title:
Decoupling between first sound and second sound in $^3$He - superfluid
  $^4$He mixtures

abstract:
  Bulk superfluid helium supports two sound modes: first sound is an ordinary
pressure wave, while second sound is a temperature wave, unique to inviscid
superfluid systems. These sound modes do not usually exist independently, but
rather variations in pressure are accompanied by variations in temperature, and
vice versa. We studied the coupling between first and second sound in dilute
$^3$He - superfluid $^4$He mixtures, between 1.6 K and 2.2 K, at $^3$He
concentrations ranging from 0 to 11 %, under saturated vapor pressure, using a
quartz tuning fork oscillator. Second sound coupled to first sound can create
anomalies in the resonance response of the fork, which disappear only at very
specific temperatures and concentrations, where two terms governing the
coupling cancel each other, and second sound and first sound become decoupled.


title:
Influence of differential elastic nucleon-nucleon cross section on
  stopping and collective flows in heavy-ion collisions at intermediate
  energies

abstract:
  By considering three different Nucleon-Nucleon (NN) elastic differential
cross sections: the Cugnon \emph{et al.} parameterized differential cross
section [Nucl. Instrum. Methods Phys. Res., Sect. \textbf{B111}, 215 (1996)],
and the differential cross section derived from the collision term of the
self-consistent relativistic Boltzmann-Uehling-Uhlenbeck equation proposed by
Mao \emph{et al.} [Z.\ Phys.\ A {\bf 347}, 173 (1994)], as well as the
isotropic differential cross section, within the newly updated version of the
ultrarelativistic quantum molecular dynamics (UrQMD) model, the influence of
the differential elastic NN cross section on various observables (e.g., nuclear
stopping, both the rapidity and transverse-velocity dependence of the directed
and elliptic flows) in Au+Au collisions at beam energies 150, 250, 400, and 800
MeV$/$nucleon is investigated. By comparing calculations with those three
differential cross sections, it is found that the nuclear stopping power, the
directed and elliptic flows are affected to some extent by the differential
cross sections, and the impact of differential cross section on those
observables becomes more visible as the beam energy increases. The effect on
the elliptic flow difference $v_{2}^{n}$-$v_{2}^{H}$ and ratio
$v_{2}^{n}$/$v_{2}^{H}$ of neutrons versus hydrogen isotopes ($Z=1$), which
have been used as sensitive observables for probing nuclear symmetry energy at
high densities, is weak.


title: A no-go theorem for the continuum limit of a periodic quantum spin chain

abstract:
  We show that the Hilbert space formed from a block spin renormalization
construction of a cyclic quantum spin chain (based on the Temperley-Lieb
algebra) does not support a chiral conformal field theory whose Hamiltonian
generates translation on the circle as a continuous limit of the rotations on
the lattice.


title:
Production of $^3$He in Rocks by Reactions Induced by Particles of the
  Nuclear-Active and Muon Components of Cosmic Rays: Geological and
  Petrological Implications

abstract:
  The paper presents data on the production of the $^3$He nuclide in rocks
under the effect of cosmic-ray particles. The origin of the nuclide in the
ground in neutron- and proton-induced spallation reactions, reactions induced
by high-energy muons, and negative muon capture reactions is analyzed. The
cross sections of reactions producing $^3$He and $^3$H are calculated by means
of numerical simulations with the GEANT4 simulation toolkit. The production
rate of the $^3$He nuclide in the ground is evaluated for the average level of
solar activity at high geomagnetic latitudes and at sea level. It is proved
that the production of $^3$He in near-surface ground layers by spallation
reactions induced by cosmic-ray protons may be approximately 10% of the total
production rate of cosmogenic $^3$He. At depths of 10-50 m.w.e., the
accumulation of $^3$He is significantly contributed by reactions induced by
cosmic-ray muons. Data presented in the paper make it possible to calculate the
accumulation rate of $^3$He in a rock depending on depth that is necessary for
the evaluation of the exposure time of the magmatic or metamorphic complex on
the Earth's surface ($^3$He dating).


title: On five dimensional Sasakian Lie algebras with trivial center

abstract:
  We show that every five-dimensional Sasakian Lie algebra with trivial center
is $\varphi$-symmetric. Moreover starting from a particular Sasakian structure
on the Lie group $SL(2,\mathbb{R})\times\text{Aff}(\mathbb{R})$ we obtain a
family of contact metric $(k,\mu)$ structures whose Boeckx invariants assume
all values less than $-1$.


title: Weak de-localization in graphene on a ferromagnetic insulating film

abstract:
  Graphene has been predicted to develop a magnetic moment by proximity effect
when placed on a ferromagnetic film, a promise that could open exciting
possibilities in the fields of spintronics and magnetic data recording. In this
work, we study in detail the interplay between the magnetoresistance of
graphene and the magnetization of an underlying ferromagnetic insulating film.
A clear correlation between both magnitudes is observed but we find, through a
careful modelling of the magnetization and the weak localization measurements,
that such correspondence can be explained by the effects of the magnetic stray
fields arising from the ferromagnetic insulator. Our results emphasize the
complexity arising at the interface between magnetic and two-dimensional
materials.


title: The DECam Minute Cadence Survey I

abstract:
  We present the first results from a minute cadence survey of a three square
degree field obtained with the Dark Energy Camera. We imaged part of the
Canada-France-Hawaii Telescope Legacy Survey area over eight half-nights. We
use the stacked images to identify 111 high proper motion white dwarf
candidates with g $\leq24.5$ mag and search for eclipse-like events and other
sources of variability. We find a new g = 20.64 mag pulsating ZZ Ceti star with
pulsation periods of 11-13 min. However, we do not find any transiting
planetary companions in the habitable zone of our target white dwarfs. Given
the probability of eclipses of 1% and our observing window from the ground, the
non-detection of such companions in this first field is not surprising. Minute
cadence DECam observations of additional fields will provide stringent
constraints on the frequency of planets in the white dwarf habitable zone.


title:
Shall we collaborate? A model to analyse the benefits of information
  sharing

abstract:
  Nowadays, both the amount of cyberattacks and their sophistication have
considerably increased, and their prevention is of concern of most of
organizations. Cooperation by means of information sharing is a promising
strategy to address this problem, but unfortunately it poses many challenges.
Indeed, looking for a win-win environment is not straightforward and
organizations are not properly motivated to share information. This work
presents a model to analyse the benefits and drawbacks of information sharing
among organizations that presents a certain level of dependency. The proposed
model applies functional dependency network analysis to emulate attacks
propagation and game theory for information sharing management. We present a
simulation framework implementing the model that allows for testing different
sharing strategies under several network and attack settings. Experiments using
simulated environments show how the proposed model provides insights on which
conditions and scenarios are beneficial for information sharing.


title:
Vacuum particle-antiparticle creation in strong fields as a field
  induced phase transition

abstract:
  The features of vacuum particle creation in an external classical field are
studied for simplest external field models in $3 + 1$ dimensional QED. The
investigation is based on a kinetic equation that is a nonperturbative
consequence of the fundamental equations of motion of QED. The observed
features of the evolution of the system apply on the qualitative level also for
systems of other nature and therefore are rather general. Examples from
cosmology and condensed matter physics illustrate this statement. The common
basis for the description of these systems are kinetic equations for vacuum
particle creation belonging to the class of integro-differential equations of
non-Markovian type with fastly oscillating kernel. This allows to characterize
processes of this type as belonging to the class of field induced phase
transitions.


title:
XQ-100: A legacy survey of one hundred 3.5 < z < 4.5 quasars observed
  with VLT/XSHOOTER

abstract:
  We describe the execution and data reduction of the European Southern
Observatory Large Programme "Quasars and their absorption lines: a legacy
survey of the high-redshift universe with VLT/XSHOOTER" (hereafter `XQ-100').
XQ-100 has produced and made publicly available an homogeneous and high-quality
sample of echelle spectra of 100 QSOs at redshifts z~3.5-4.5 observed with full
spectral coverage from 315 to 2500 nm at a resolving power ranging from R~4000
to 7000, depending on wavelength. The median signal-to-noise ratios are 33, 25
and 43, as measured at rest-frame wavelengths 1700, 3000 and 3600 Angstrom,
respectively. This paper provides future users of XQ-100 data with the basic
statistics of the survey, along with details of target selection, data
acquisition and data reduction. The paper accompanies the public release of all
data products, including 100 reduced spectra. XQ-100 is the largest
spectroscopic survey to date of high-redshift QSOs with simultaneous rest-frame
UV/optical coverage, and as such enables a wide range of extragalactic
research, from cosmology and galaxy evolution to AGN astrophysics.


title:
Current fluctuations in nanopores: the effects of electrostatic and
  hydrodynamic interactions

abstract:
  Using nonequilibrium Langevin dynamics simulations of an electrolyte with
explicit solvent particles, we investigate the effect of hydrodynamic
interactions on the power spectrum of ionic nanopore currents. At low
frequency, we find a power-law dependence of the power spectral density, with
an exponent depending on the ion density. Surprisingly, however, the exponent
is not affected by the presence of the neutral solvent particles. We conclude
that hydrodynamic interactions do not affect the shape of the power spectrum in
the frequency range studied.


title: Observation of topological Uhlmann phases with superconducting qubits

abstract:
  Topological insulators and superconductors at finite temperature can be
characterized by the topological Uhlmann phase. However, a direct experimental
measurement of this invariant has remained elusive in condensed matter systems.
Here, we report a measurement of the topological Uhlmann phase for a
topological insulator simulated by a system of entangled qubits in the IBM
Quantum Experience platform. By making use of ancilla states, otherwise
unobservable phases carrying topological information about the system become
accessible, enabling the experimental determination of a complete phase diagram
including environmental effects. We employ a state-independent measurement
protocol which does not involve prior knowledge of the system state. The
proposed measurement scheme is extensible to interacting particles and
topological models with a large number of bands.