title: The Spin Nernst effect in Tungsten

abstract:
  The spin Hall effect allows generation of spin current when charge current is
passed along materials with large spin orbit coupling. It has been recently
predicted that heat current in a non-magnetic metal can be converted into spin
current via a process referred to as the spin Nernst effect. Here we report the
observation of the spin Nernst effect in W. In W/CoFeB/MgO heterostructures, we
find changes in the longitudinal and transverse voltages with magnetic field
when temperature gradient is applied across the film. The field-dependence of
the voltage resembles that of the spin Hall magnetoresistance. A comparison of
the temperature gradient induced voltage and the spin Hall magnetoresistance
allows direct estimation of the spin Nernst angle. We find the spin Nernst
angle of W to be similar in magnitude but opposite in sign with its spin Hall
angle. Interestingly, under an open circuit condition, such sign difference
results in spin current generation larger than otherwise. These results
highlight the distinct characteristics of the spin Nernst and spin Hall
effects, providing pathways to explore materials with unique band structures
that may generate large spin current with high efficiency.


title:
Enhancing Hot Carrier Collection for Solar Water Splitting with
  Plasmonic Titanium Nitride

abstract:
  The use of hot electrons generated from the decay of surface plasmons is a
new paradigm to increase the conversion yield in solar energy technologies.
Titanium nitride (TiN) is an emerging plasmonic ceramic that offers
compatibility with CMOS technology, corrosion resistance, as well as mechanical
strength and durability thus outperforming noble metals (i.e., Au, Ag) in terms
of cost, mechanical, chemical and thermal stability. Here, we show that
plasmonic TiN nanoparticles produce 25% higher photocurrent enhancement than Au
nanoparticles decorated on TiO2 nanowires for photoelectrochemical water
splitting. Our results highlight that TiN offers superior performance in hot
carrier generation due to enhanced absorption efficiency, increased electron
mean free path, and the ability to form an Ohmic junction with TiO2, thus
enabling an extremely efficient electron collection not achievable with
plasmonic Au nanoparticles. Our findings show that transition metal nitrides
enable practical plasmonic devices with enhanced performance for solar energy
conversion.


title:
Influence of spin-orbit coupling on the magnetic dipole term
  $T_{\alpha}$

abstract:
  The influence of the spin-orbit coupling (SOC) on the magnetic dipole term
$T_{\alpha}$ is studied across a range of systems in order to check whether the
$T_{\alpha}$ term can be eliminated from analysis of x-ray magnetic circular
dichroism spectra done via the spin moment sum rule. Fully relativistic
Korringa-Kohn-Rostoker (KKR) Green function calculations for Co monolayers and
adatoms on Cu, Pd, Ag, Pt, and Au (111) surfaces were performed to verify
whether the sum over magnetic dipole terms $T_{x}+T_{y}+T_{z}$ is zero and
whether the angular dependence of the \ta\ term goes as $3\cos^{2}\theta-1$. It
follows that there are circumstances when the influence of the SOC on
$T_{\alpha}$ cannot be neglected even for 3$d$ atoms, where the SOC is
nominally small. The crucial factor appears to be the dimensionality of the
system: for 3$d$ adatoms, the influence of SOC on $T_{\alpha}$ can be
significant while for monolayers it is always practically negligible. Apart
from the dimensionality, hybridization between adatom and substrate states is
also important: small hybridization enhances the importance of the SOC and vice
versa.


title: On sets defining few ordinary circles

abstract:
  An ordinary circle of a set $P$ of $n$ points in the plane is defined as a
circle that contains exactly three points of $P$. We show that if $P$ is not
contained in a line or a circle, then $P$ spans at least $\frac{1}{4}n^2 -
O(n)$ ordinary circles. Moreover, we determine the exact minimum number of
ordinary circles for all sufficiently large $n$ and describe all point sets
that come close to this minimum. We also consider the circle variant of the
orchard problem. We prove that $P$ spans at most $\frac{1}{24}n^3 - O(n^2)$
circles passing through exactly four points of $P$. Here we determine the exact
maximum and the extremal configurations for all sufficiently large $n$.
  These results are based on the following structure theorem. If $n$ is
sufficiently large depending on $K$, and $P$ is a set of $n$ points spanning at
most $Kn^2$ ordinary circles, then all but $O(K)$ points of $P$ lie on an
algebraic curve of degree at most four. Our proofs rely on a recent result of
Green and Tao on ordinary lines, combined with circular inversion and some
classical results regarding algebraic curves.


title: Excitation of nonlinear ion acoustic waves in CH plasmas

abstract:
  Excitation of nonlinear ion acoustic wave (IAW) by an external electric field
is demonstrated by Vlasov simulation. The frequency calculated by the
dispersion relation with no damping is verified much closer to the resonance
frequency of the small-amplitude nonlinear IAW than that calculated by the
linear dispersion relation. When the wave number $ k\lambda_{De} $ increases,
the linear Landau damping of the fast mode (its phase velocity is greater than
any ion's thermal velocity) increases obviously in the region of $ T_i/T_e <
0.2 $ in which the fast mode is weakly damped mode. As a result, the deviation
between the frequency calculated by the linear dispersion relation and that by
the dispersion relation with no damping becomes larger with $k\lambda_{De}$
increasing. When $k\lambda_{De}$ is not large, such as $k\lambda_{De}=0.1, 0.3,
0.5$, the nonlinear IAW can be excited by the driver with the linear frequency
of the modes. However, when $k\lambda_{De}$ is large, such as
$k\lambda_{De}=0.7$, the linear frequency can not be applied to exciting the
nonlinear IAW, while the frequency calculated by the dispersion relation with
no damping can be applied to exciting the nonlinear IAW.


title:
Dynamics of the Ericksen-Leslie Equations with General Leslie Stress I:
  The Incompressible Isotropic Case

abstract:
  The Ericksen-Leslie model for nematic liquid crystals in a bounded domain
with general Leslie and isotropic Ericksen stress is studied in the case of a
non-isothermal and incompressible fluid. This system is shown to be locally
well-posed in the $L_p$-setting, and a dynamic theory is developed. The
equilibria are identified and shown to be normally stable. In particular, a
local solution extends to a unique, global strong solution provided the initial
data are close to an equilibrium or the solution is eventually bounded in the
topology of the natural state manifold. In this case, the solution converges
exponentially to an equilibrium, in the topology of the state manifold. The
above results are proven {\em without} any structural assumptions on the Leslie
coefficients and in particular {\em without} assuming Parodi's relation.


title: High girth hypergraphs with unavoidable monochromatic or rainbow edges

abstract:
  A classical result of Erd\H{o}s and Hajnal claims that for any integers $k,
r, g \geq 2$ there is an $r$-uniform hypergraph of girth at least $g$ with
chromatic number at least $k$. This implies that there are sparse hypergraphs
such that in any coloring of their vertices with at most $k-1$ colors there is
a monochromatic hyperedge. We show that for any integers $r, g\geq 2$ there is
an $r$-uniform hypergraph of girth at least $g$ such that in any coloring of
its vertices there is either a monochromatic or a rainbow (totally
multicolored) edge. We give a probabilistic and a deterministic proof of this
result.


title: Lo Gnomone Clementino Astronomia Meridiana in Basilica

abstract:
  The Clementine Gnomon realized in 1702 by the astronomer Francesco Bianchini
(1661-1729) upon the will of Pope Clement XI (1700-1721) in the Basilica of
Santa Maria degli Angeli in Rome is fully reviewed about its scientific
functions.


title: Fluctuations and the QCD Phase Diagram

abstract:
  In this contribution we will discuss how the study of various fluctuation
observables may be used to explore the phase diagram of the strong interaction.
We will briefly summarize the present study of experimental and theoretical
research in this area. We will then discuss various corrections and issues
which need to be understood and applied for a meaningful comparison of
experimental measurements with theoretical predictions. This contribution is
dedicated to Andrzej Bialas on the occasion of his $80^{\mathrm{th}}$ birthday.


title: The naturality of natural deduction

abstract:
  Developing a suggestion by Russell, Prawitz showed how the usual natural
deduction inference rules for disjunction, conjunction and absurdity can be
derived using those for implication and the second order quantifier in
propositional intuitionistic second order logic $NI^2$. It is however well
known that the translation does not preserve the relations of identity among
derivations induced by the permutative conversions and immediate expansions for
the definable connectives, at least when the equational theory of $NI^2$ is
assumed to consist only of $\beta$ and $\eta$ equations. On the basis of the
categorial interpretation of $NI^2$, we introduce a new class of equations
expressing what in categorial terms is a naturality condition satisfied by the
transformations interpreting $NI^2$-derivations. We show that the
Russell-Prawitz translation does preserve identity of proof with respect to the
enriched system by highlighting the fact that naturality corresponds to a
generalized permutation principle. We show that these result generalize some
facts which have gone so far unnoticed, namely that the Russell-Prawitz
translation maps particular classes of instances of the equations governing
disjunction (and the other definable connectives) onto equations which are
already included in the $\beta\eta$ equational theory of $NI^2$. Finally, we
compare our approach with the one proposed by Ferreira and Ferreira and show
that the naturality condition suggests a generalization of their methods to a
wider class of formulas.


title:
How many times can the volume of a convex polyhedron be increased by
  isometric deformations?

abstract:
  We prove that the answer to the question of the title is `as many times as
you want.' More precisely, given any constant $c>0$, we construct two oblique
triangular bipyramids, $P$ and $Q$, such that $P$ is convex, $Q$ is nonconvex
and intrinsically isometric to $P$, and $\textrm{vol} Q>c\cdot \textrm{vol}
P>0$.


title:
Measurement of the total cross section from elastic scattering in $pp$
  collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

abstract:
  A measurement of the total $pp$ cross section at the LHC at $\sqrt{s}=8$ TeV
is presented. An integrated luminosity of $500$ $\mu$b$^{-1}$ was accumulated
in a special run with high-$\beta^{\star}$ beam optics to measure the
differential elastic cross section as a function of the Mandelstam momentum
transfer variable $t$. The measurement is performed with the ALFA sub-detector
of ATLAS. Using a fit to the differential elastic cross section in the $-t$
range from $0.014$ GeV$^2$ to $0.1$ GeV$^2$ to extrapolate $t\rightarrow 0$,
the total cross section, $\sigma_{\mathrm{tot}}(pp\rightarrow X)$, is measured
via the optical theorem to be: $\sigma_{\mathrm{tot}}(pp\rightarrow X) =
{96.07} \; \pm 0.18 \; ({{stat.}}) \pm 0.85 \; ({{exp.}}) \pm 0.31 \; ({extr.})
\; {mb} \;,$ where the first error is statistical, the second accounts for all
experimental systematic uncertainties and the last is related to uncertainties
in the extrapolation $t\rightarrow 0$. In addition, the slope of the
exponential function describing the elastic cross section at small $t$ is
determined to be $B = 19.74 \pm 0.05 \; ({{stat.}}) \pm 0.23 \; ({{syst.}}) \;
{GeV}^{-2}$.


title:
The FLARE mission: Deep and Wide-field 1-5$\mu$m Imaging and
  Spectroscopy for the Early Universe: a proposal for M5 Cosmic Vision call

abstract:
  FLARE (First Light And Reionization Explorer) is a space mission that will be
submitted to ESA (M5 call). Its primary goal (about 80% of lifetime) is to
identify and study galaxies that dwell in the universe before the end of the
reionization up to about z = 15, a redshift that might not be statistically
reachable for JWST, Euclid and WFIRST. A secondary objective (about 20% of
lifetime) is to survey star formation in the Milky Way.
  The strategy selected for FLARE optimizes the science return: imaging and
spectroscopic integral-field observations will be carried out simultaneously on
two parallel focal planes and over very wide instantaneous fields of view.
FLARE will feature an instantaneous field of view of about 0.2 deg$^2$ with
0.2-arcsec pixels and an instantaneous integral-field spectroscopic field of
view of about 1 arcmin$^2$ with R = 500 - 1000 and an angular resolution of
about 0.4 arcsec. To detect first-light galaxies, the imaging and spectroscopic
survey (parallel observations over about 6 years) will reach m$_{AB}$ = 28 and
f$_{\lambda}$ = 10$^{-18}$ erg/cm$^2$/S.
  FLARE will help addressing two of ESA's Cosmic Vision themes: a) "How did the
universe originate and what is it made of?" and b) "What are the conditions for
planet formation and the emergence of life?" and more specifically, "From gas
and dust to stars and planets".
  FLARE will provide to the ESA community a leading position to statistically
study the early universe after JWST's deep but pin-hole surveys. Moreover, the
instrumental development of wide-field imaging and wide-field integral-field
spectroscopy in space will be a major breakthrough after making them available
on ground-based telescopes.


title: On Stark elements of arbitrary weight and their $p$-adic families

abstract:
  We develop a detailed arithmetic theory related to special values at
arbitrary integers of the Artin $L$-series of linear characters. To do so we
define canonical generalized Stark elements of arbitrary `rank' and `weight',
thereby extending the classical theory of Rubin-Stark elements. We then
formulate an extension to arbitrary weight of the refined version of the
Rubin-Stark Conjecture that we studied in an earlier article and also show that
generalized Stark elements constitute a $p$-adic family by formulating precise
conjectural congruence relations between elements of differing weights. We
prove both of these conjectures in several important cases.


title: Bayes-factor of the ATLAS diphoton excess

abstract:
  We present a calculation of Bayes-factors for the digamma resonance
($\digamma$) versus the SM in light of ATLAS 8 TeV 20.3/fb, 13 TeV 3.2/fb and
13 TeV 15.4/fb data, sidestepping any difficulties in interpreting
significances in frequentist statistics. We matched, wherever possible,
parameterisations in the ATLAS analysis. We calculated that the plausibility of
the $\digamma$ versus the Standard Model increased by about eight in light of
the 8 TeV 20.3/fb and 13 TeV 3.2/fb ATLAS data, somewhat justifying interest in
$\digamma$ models. All told, however, in light of 15.4/fb data, the $\digamma$
was disfavoured by about 0.7.


title: The quest to find an electric dipole moment of the neutron

abstract:
  Until now no electric dipole moment of the neutron (nEDM) has been observed.
Why it is so vanishingly small, escaping detection for the last 65 years, is
not easy to explain. In general it is considered as one of the most sensitive
probes for the violation of the combined symmetry of charge and parity (CP). A
discovery could shed light on the poorly understood matter/antimatter asymmetry
of the Universe. The neutron EDM might one day help to distinguish different
sources of CP-violation in combination with measurements of paramagnetic
molecules, diamagnetic atoms and other nuclei. This review presents an overview
of the most important concepts in searches for an nEDM as well as a brief
overview of the worldwide efforts.


title: On the genealogy of branching random walks and of directed polymers

abstract:
  It is well known that the mean field theory of directed polymers in a random
medium exhibits replica symmetry breaking with a distribution of overlaps which
consists of two delta functions. Here we show that the leading finite size
correction to this distribution of overlaps has a universal character which can
be computed explicitly. Our results can also be interpreted as genealogical
properties of branching Brownian motion or of branching random walks.


title:
Superconnections and An Intrinsic Gauss-Bonnet-Chern Formula for Finsler
  Manifolds

abstract:
  In this paper, we establish an intrinsic Gauss-Bonnet-Chern formula for
Finsler manifolds by using the Mathai-Quillen's superconnection formalism, in
which no extra vector field is involved. Furthermore, we prove a more general
Lichnerowicz formula in this direction through a geometric localization
procedure.


title:
Quantum spin Hall insulators in centrosymmetric thin films composed from
  topologically trivial BiTeI trilayers

abstract:
  The quantum spin Hall insulators predicted ten years ago and now
experimentally observed are instrumental for a breakthrough in nanoelectronics
due to non-dissipative spin-polarized electron transport through their edges.
For this transport to persist at normal conditions, the insulators should
possess a sufficiently large band gap in a stable topological phase. Here, we
theoretically show that quantum spin Hall insulators can be realized in
ultra-thin films constructed from a trivial band insulator with strong
spin-orbit coupling. The thinnest film with an inverted gap large enough for
practical applications is a centrosymmetric sextuple layer built out of two
inversely stacked non-centrosymmetric BiTeI trilayers. This nontrivial sextuple
layer turns out to be the structure element of an artificially designed strong
three-dimensional topological insulator Bi$_2$Te$_2$I$_2$. We reveal general
principles of how a topological insulator can be composed from the structure
elements of the BiTeX family (X=I, Br, Cl), which opens new perspectives
towards engineering of topological phases.


title:
Quantum-fluctuation-driven crossover from a dilute Bose-Einstein
  condensate to a macro-droplet in a dipolar quantum fluid

abstract:
  In a joint experimental and theoretical effort, we report on the formation of
a macro-droplet state in an ultracold bosonic gas of erbium atoms with strong
dipolar interactions. By precise tuning of the s-wave scattering length below
the so-called dipolar length, we observe a smooth crossover of the ground state
from a dilute Bose-Einstein condensate (BEC) to a dense macro-droplet state of
more than $10^4$ atoms. Based on the study of collective excitations and loss
features, we quantitative prove that quantum fluctuations stabilize the
ultracold gas far beyond the instability threshold imposed by mean-field
interactions. Finally, we perform expansion measurements, showing the evolution
of the normal BEC towards a three-dimensional self-bound state and show that
the interplay between quantum stabilization and three-body losses gives rise to
a minimal expansion velocity at a finite scattering length.


title: The rich polymorphic behavior of Wigner bilayers

abstract:
  Self-assembly into target structures is an efficient material design
strategy. Combining analytical calculations and computational techniques of
evolutionary and Monte Carlo types, we report about a remarkable structural
variability of Wigner bilayer ground states, when charges are confined between
parallel charged plates. Changing the inter-layer separation, or the plate
charge asymmetry, a cascade of ordered patterns emerges. At variance with the
symmetric case phenomenology, the competition between commensurability features
and charge neutralization leads to long range attraction, appearance of
macroscopic charges, exotic phases, and non conventional phase transitions with
distinct critical indices, offering the possibility of a subtle, but precise
and convenient control over patterns.


title:
Probing the astrophysical origin of high-energy cosmic-ray electrons
  with Monte Carlo simulation

abstract:
  High-energy cosmic-ray electrons reveal some remarkable spectral features,
the most noteworthy of which is the rise in the positron fraction above 10~GeV.
Due to strong energy loss during propagation, these particles can reach Earth
only from nearby sources. Yet, the exact nature of these sources, which most
likely manifest themselves in the observed anomalies, remains elusive. The many
explanations put forward to resolve this case range from standard astrophysics
to exotic physics. In this paper, we discuss the possible astrophysical origin
of high-energy cosmic-ray electrons through a fully three-dimensional
time-dependent Monte Carlo simulation. This approach, which takes advantage of
the intrinsic random nature of cosmic-ray diffusive propagation, provides
valuable information on the electron-by-electron fluctuations, making it
particularly suitable for analyzing in depth the single-source scenario.


title: Avalanche of entanglement and correlations at quantum phase transitions

abstract:
  We study the ground-state entanglement in the quantum Ising model with
nearest neighbor ferromagnetic coupling $J$ and find a sequential increase of
entanglement depth with growing $J$. This entanglement avalanche starts with
two-point entanglement, as measured by the concurrence, and continues via the
three-tangle and four-tangle, until finally, deep in the ferromagnetic phase
for $J=\infty$, arriving at pure $\ell$-partite (GHZ type) entanglement of all
$\ell$ spins. Comparison with the two, three, and four-point correlations
reveals a similar sequence and shows strong ties to the above entanglement
measures for small $J$. However, we also find a partial inversion of the
hierarchy, where the four-point correlation exceeds the three- and two-point
correlations, well before the critical point is reached. Qualitatively similar
behavior is also found for the Bose-Hubbard model, suggesting that this is a
general feature of a quantum phase transition. This should have far reaching
consequences for approximations starting from a mean-field limit.


title: Latent Variable Discovery Using Dependency Patterns

abstract:
  The causal discovery of Bayesian networks is an active and important research
area, and it is based upon searching the space of causal models for those which
can best explain a pattern of probabilistic dependencies shown in the data.
However, some of those dependencies are generated by causal structures
involving variables which have not been measured, i.e., latent variables. Some
such patterns of dependency "reveal" themselves, in that no model based solely
upon the observed variables can explain them as well as a model using a latent
variable. That is what latent variable discovery is based upon. Here we did a
search for finding them systematically, so that they may be applied in latent
variable discovery in a more rigorous fashion.


title: Gerbil: A Fast and Memory-Efficient $k$-mer Counter with GPU-Support

abstract:
  A basic task in bioinformatics is the counting of $k$-mers in genome strings.
The $k$-mer counting problem is to build a histogram of all substrings of
length $k$ in a given genome sequence. We present the open source $k$-mer
counting software Gerbil that has been designed for the efficient counting of
$k$-mers for $k\geq32$. Given the technology trend towards long reads of
next-generation sequencers, support for large $k$ becomes increasingly
important. While existing $k$-mer counting tools suffer from excessive memory
resource consumption or degrading performance for large $k$, Gerbil is able to
efficiently support large $k$ without much loss of performance. Our software
implements a two-disk approach. In the first step, DNA reads are loaded from
disk and distributed to temporary files that are stored at a working disk. In a
second step, the temporary files are read again, split into $k$-mers and
counted via a hash table approach. In addition, Gerbil can optionally use GPUs
to accelerate the counting step. For large $k$, we outperform state-of-the-art
open source $k$-mer counting tools for large genome data sets.


title: ARTist: The Android Runtime Instrumentation and Security Toolkit

abstract:
  We present ARTist, a compiler-based application instrumentation solution for
Android. ARTist is based on the new ART runtime and the on-device dex2oat
compiler of Android, which replaced the interpreter-based managed runtime (DVM)
from Android version 5 onwards. Since dex2oat is yet uncharted, our approach
required first and foremost a thorough study of the compiler suite's internals
and in particular of the new default compiler backend Optimizing. We document
the results of this study in this paper to facilitate independent research on
this topic and exemplify the viability of ARTist by realizing two use cases.
Moreover, given that seminal works like TaintDroid hitherto depend on the now
abandoned DVM, we conduct a case study on whether taint tracking can be
re-instantiated using a compiler-based instrumentation framework. Overall, our
results provide compelling arguments for preferring compiler-based
instrumentation over alternative bytecode or binary rewriting approaches.


title: Multi-Fingered Robotic Grasping: A Primer

abstract:
  This technical report presents an introduction to different aspects of
multi-fingered robot grasping. After having introduced relevant mathematical
background for modeling, form and force closure are discussed. Next, we present
an overview of various grasp planning algorithms with the objective of
illustrating different approaches to solve this problem. Finally, we discuss
grasp performance benchmarking.


title:
Signatures of nonlinear mode interactions in the pulsating hot B
  subdwarf star KIC 10139564

abstract:
  We analyse 38-month of contiguous short-cadence data, concentrating on mode
multiplets induced by the star rotation and on frequencies forming linear
combinations that show intriguing behaviors during the course of the
observations. We find clear signatures that point toward nonlinear effects
predicted by resonant mode coupling mechanisms. These couplings can induce
various mode behaviors for the components of multiplets and for frequencies
related by linear relationships. We find that a triplet at 5760\,$\mu$Hz, a
quintuplet at 5287\,$\mu$Hz and a ($\ell>2$) multiplet at 5412\,$\mu$Hz, all
induced by rotation, show clear frequency and amplitude modulations which are
typical of the so-called intermediate regime of a resonance between the
components. One triplet at 316\,$\mu$Hz and a doublet at 394\,$\mu$Hz show
modulated amplitude and constant frequency which can be associated with a
narrow transitory regime of the resonance. Another triplet at 519\,$\mu$Hz
appears to be in a frequency lock regime where both frequency and amplitude are
constant. Additionally, three linear combination of frequencies near
6076\,$\mu$Hz also show amplitude and frequency modulations, which are likely
related to a three-mode direct resonance. The identified frequency and
amplitude modulations are the first clear-cut signatures of nonlinear resonant
couplings occurring in pulsating hot B subdwarf stars. However, the observed
behaviors suggest that the resonances occurring in these stars usually follow
more complicated patterns than the simple predictions from current nonlinear
theoretical frameworks. These results should therefore motivate further work to
develop the theory of nonlinear stellar pulsations, considering that stars like
KIC~10139564 now offer remarkable testbeds to do so.


title: LWB and FS-LWB implementation for Sky platform using Contiki

abstract:
  The low-power wireless bus (LWB) is a highly efficient communication protocol
for wireless sensor networks (WSN). However, a lack of open implementation for
this protocol prompted the implementation of the protocol for the most common
platform of WSN related research, the sky nodes using the Contiki operating
system. This document provides the detailed description of the implementation.
  A forwarder-selection mechanism is developed to improve energy-efficiency of
LWB in data collection scenario. The implementation also consists the forwarder
selection mechanism. One can either use the original features of LWB or enforce
the forwarder selection mechanism.


title:
Asymptotic Properties of Primal-Dual Algorithm for Distributed
  Stochastic Optimization Over Random Networks

abstract:
  This paper studies a distributed stochastic optimization problem over random
networks with imperfect communications subject to a global constraint, which is
the intersection of local constraint sets assigned to agents. The global cost
function is the sum of local cost functions, each of which is the expectation
of a random cost function. By incorporating the augmented Lagrange technique
with the projection method, a stochastic approximation based distributed
primal-dual algorithm is proposed to solve the problem. Each agent updates its
estimate by using the local observations and the information derived from
neighbors. For the constrained problem, the estimates are first shown to be
bounded almost surely (a.s.), and then are proved to converge to the optimal
solution set a.s. Furthermore, the asymptotic normality and efficiency of the
algorithm are addressed for the unconstrained case. The results demonstrate the
influence of random networks, communication noises, and gradient errors on the
performance of the algorithm. Finally, numerical simulations demonstrate the
theoretic results.


title:
Functional central limit theorems for stationary Hawkes processes and
  application to infinite-server queues

abstract:
  A univariate Hawkes process is a simple point process that is self-exciting
and has clustering effect. The intensity of this point process is given by the
sum of a baseline intensity and another term that depends on the entire past
history of the point process. Hawkes process has wide applications in finance,
neuroscience, social networks, criminology, seismology, and many other fields.
In this paper, we prove a functional central limit theorem for stationary
Hawkes processes in the asymptotic regime where the baseline intensity is
large. The limit is a non-Markovian Gaussian process with dependent increments.
We use the resulting approximation to study an infinite-server queue with
high-volume Hawkes traffic. We show that the queue length process can be
approximated by a Gaussian process, for which we compute explicitly the
covariance function and the steady-state distribution. We also extend our
results to multivariate stationary Hawkes processes and establish limit
theorems for infinite-server queues with multivariate Hawkes traffic.


title: A higher-dimensional Siegel-Walfisz theorem

abstract:
  The Green-Tao-Ziegler theorem provides asymptotics for the number of prime
tuples of the form $(\psi_1(n),\ldots,\psi_t(n))$ when $n$ ranges among the
integer vectors of a convex body $K\subset [-N,N]^d$ and
$\Psi=(\psi_1,\ldots,\psi_t)$ is a system of affine-linear forms whose linear
coefficients remain bounded (in terms of $N$). In the $t=1$ case, the
Siegel-Walfisz theorem shows that the asymptotic still holds when the
coefficients vary like a power of $\log N$. We prove a higher-dimensional (i.e.
$t>1$) version of this fact.
  We provide natural examples where our theorem goes beyond the one of Green
and Tao, such as the count of arithmetic of progressions of step $\lfloor \log
N\rfloor$ times a prime in the primes up to $N$. We also apply our theorem to
the determination of asymptotics for the number of linear patterns in a dense
subset of the primes, namely the primes $p$ for which $p-1$ is squarefree. To
the best of our knowledge, this is the first such result in dense subsets of
primes save for congruence classes.


title:
Self-assembly of two-dimensional binary quasicrystals: A possible route
  to a DNA quasicrystal

abstract:
  We use Monte Carlo simulations and free-energy techniques to show that binary
solutions of penta- and hexavalent two-dimensional patchy particles can form
thermodynamically stable quasicrystals even at very narrow patch widths,
provided their patch interactions are chosen in an appropriate way. Such patchy
particles can be thought of as a coarse-grained representation of DNA multi-arm
`star' motifs, which can be chosen to bond with one another very specifically
by tuning the DNA sequences of the protruding arms. We explore several possible
design strategies and conclude that DNA star tiles that are designed to
interact with one another in a specific but not overly constrained way could
potentially be used to construct soft quasicrystals in experiment. We verify
that such star tiles can form stable dodecagonal motifs using oxDNA, a
realistic coarse-grained model of DNA.


title:
Stability estimates for linearized near-field phase retrieval in X-ray
  phase contrast imaging

abstract:
  Propagation-based X-ray phase contrast enables nanoscale imaging of
biological tissue by probing not only the attenuation, but also the real part
of the refractive index of the sample. Since only intensities of diffracted
waves can be measured, the main mathematical challenge consists in a
phase-retrieval problem in the near-field regime. We treat an often used
linearized version of this problem known as contract transfer function model.
Surprisingly, this inverse problem turns out to be well-posed assuming only a
compact support of the imaged object. Moreover, we establish bounds on the
Lipschitz stability constant. In general this constant grows exponentially with
the Fresnel number of the imaging setup. However, both for homogeneous objects,
characterized by a fixed ratio of the induced refractive phase shifts and
attenuation, and in the case of measurements at two distances, a much more
favorable algebraic dependence on the Fresnel number can be shown. In some
cases we establish order optimality of our estimates.


title:
The asymptotics of the higher dimensional Reidemeister torsion for
  exceptional surgeries along twist knots

abstract:
  We determine the asymptotic behavior of the higher dimensional Reidemeister
torsion for the graph manifolds obtained by exceptional surgeries along twist
knots. We show that all irreducible SL(2;C)-representations of the graph
manifold are induced by irreducible metabelian representations of the twist
knot group. We also give the set of the limits of the leading coefficients in
the higher dimensional Reidemeister torsion explicitly.


title:
Thermodynamics of Horndeski black holes with non-minimal derivative
  coupling

abstract:
  We explore thermodynamic properties of a new class of Horndeski black holes
whose action contains a non-minimal kinetic coupling of a massless real scalar
and the Einstein tensor. Our treatment is based on the well-accepted
consideration, where the cosmological constant is dealt with as thermodynamic
pressure and the mass of black holes as thermodynamic enthalpy. We resort to a
newly introduced intensive thermodynamic variable, i.e., the coupling strength
of the scalar and tensor whose dimension is length square, and thus yield both
the generalized first law of thermodynamics and the generalized Smarr relation.
Our result indicates that this class of Horndeski black holes presents rich
thermodynamic behaviors and critical phenomena. Especially in the case of the
presence of an electric field, these black holes undergo two phase transitions.
Once the charge parameter exceeds its critical value, or the cosmological
parameter does not exceed its critical value, no phase transitions happen and
the black holes are stable. As a by-product, we point out that the coupling
strength acts as the thermodynamic pressure in the behavior of thermodynamics.


title:
Remarks on the geometric quantization of a class of harmonic oscillator
  type potentials

abstract:
  The conditions that must be fulfilled by a certain physical system to apply
geometric quantization prescription on it are investigated. These terms are
sought as mathematical requirements, which can be traced in an analysis of
integrable systems, from the perspective of both potential function and
Hamiltonian vector field. The answer is found in momentum map critical points.
Basically, a certain disposal of points that allow a momentum map $C^*$
isomorphism, of observables, with harmonic oscillator momentum map enforce
geometric quantization rules. Following the general theory, two newly presented
examples, which exhibits these properties, are quantified through geometric
quantization prescription. The Lennard-Jones' type potential is one of the
examples, it is known as describing molecules in interaction. We end with a
third example that shows the local isomorphism of potentials do not induce
$C^*$ isomorphism of observables.


title:
Constraints on reconstructed dark energy model from SN Ia and BAO/CMB
  observations

abstract:
  The motivation of the present work is to reconstruct a dark energy model
through the {\it dimensionless dark energy function} $X(z)$, which is the dark
energy density in units of its present value. In this paper, we have shown that
a scalar field $\phi$ having a phenomenologically chosen $X(z)$ can give rise
to a transition from a decelerated to an accelerated phase of expansion for the
universe. We have examined the possibility of constraining various cosmological
parameters (such as the deceleration parameter and the effective equation of
state parameter) by comparing our theoretical model with the latest Type Ia
Supernova (SN Ia), Baryon Acoustic Oscillations (BAO) and Cosmic Microwave
Background (CMB) radiation observations. Using the joint analysis of the SN
Ia+BAO/CMB dataset, we have also reconstructed the scalar potential from the
parametrized $X(z)$. The relevant potential is found, which comes to be a
polynomial in $\phi$. From our analysis, it has been found that the present
model favors the standard $\Lambda$CDM model within $1\sigma$ confidence level.


title: A consistent discrete version of a non-autonomous SIRVS model

abstract:
  A family of discrete non-autonomous SIRVS models with general incidence is
obtained from a continuous family of models by applying Mickens non-standard
discretization method. Conditions for the permanence and extinction of the
disease and the stability of disease-free solutions are determined. The
consistency of those discrete models with the corresponding continuous model is
discussed: if the time step is sufficiently small, when we have extinction
(respectively permanence) for the continuous model we also have extinction
(respectively permanence) for the corresponding discrete model. Some numerical
simulations are carried out to compare the different possible discretizations
of our continuous model using real data.


title:
Experimental demonstration of the connection between quantum
  contextuality and graph theory

abstract:
  We report a method that exploits a connection between quantum contextuality
and graph theory to reveal any form of quantum contextuality in high-precision
experiments. We use this technique to identify a graph which corresponds to an
extreme form of quantum contextuality unnoticed before and test it using
high-dimensional quantum states encoded in the linear transverse momentum of
single photons. Our results open the door to the experimental exploration of
quantum contextuality in all its forms, including those needed for quantum
computation.


title:
The rotation - Lithium depletion correlation in the beta Pictoris
  association and LDB age determination

abstract:
  There is evidence in the 125-Myr Pleiades cluster, and more recently in the
5-Myr NGC 2264 cluster, that rotation plays a key role in the Lithium (Li)
depletion processes among low-mass stars. Fast rotators appear to be less
Li-depleted than equal-mass slow rotators. We intend to explore the existence
of a Li depletion - rotation connection among the beta Pictoris members at an
age of about 24 Myr, and to use such correlation either to confirm or to
improve the age estimate based on the Lithium Depletion Boundary (LDB)
modeling. We have photometrically monitored all the known members of the beta
Pictoris association with at least one Lithium equivalent width (Li EW)
measurement from the literature. We measured the rotation periods of 30 members
for the first time and retrieved from the literature the rotation periods for
other 36 members, building a catalogue of 66 members with measured rotation
period and Li EW. We find that in the 0.3 < M < 0.8 Msun range, there is a
strong correlation between rotation and Li EW. For higher mass stars, no
significant correlation is found. For very low mass stars in the Li depletion
onset, at about 0.1 Msun, data are too few to infer a significant correlation.
The observed Li EWs are compared with those predicted by the Dartmouth stellar
evolutionary models that incorporate the effects of magnetic fields. After
decorrelating the Li EW from the rotation period, we find that the hot side of
the LDB is fitted well by Li EW values corresponding to an age of 25$\pm$3 Myr
in good agreement with independent estimates from the literature.


title: Density Estimation Trees as fast non-parametric modelling tools

abstract:
  Density Estimation Trees (DETs) are decision trees trained on a multivariate
dataset to estimate its probability density function. While not competitive
with kernel techniques in terms of accuracy, they are incredibly fast,
embarrassingly parallel and relatively small when stored to disk. These
properties make DETs appealing in the resource-expensive horizon of the LHC
data analysis. Possible applications may include selection optimization, fast
simulation and fast detector calibration. In this contribution I describe the
algorithm, made available to the HEP community in a RooFit implementation. A
set of applications under discussion within the LHCb Collaboration are also
briefly illustrated.


title:
Gravitational waves and mass ejecta from binary neutron star mergers:
  Effect of the mass-ratio

abstract:
  We present new (3+1)D numerical relativity simulations of the binary neutron
star (BNS) merger and postmerger phase. We focus on a previously inaccessible
region of the binary parameter space spanning the binary's mass-ratio
$q\sim1.00-1.75$ for different total masses and equations of state, and up to
$q\sim2$ for a stiff BNS system. We study the mass-ratio effect on the
gravitational waves (GWs) and on the possible electromagnetic emission
associated to dynamical mass ejecta. We compute waveforms, spectra, and
spectrograms of the GW strain including all the multipoles up to $l=4$. The
mass-ratio has a specific imprint on the GW multipoles in the
late-inspiral-merger signal, and it affects qualitatively the spectra of the
merger remnant. The multipole effect is also studied by considering the
dependency of the GW spectrograms on the source's sky location. Unequal mass
BNSs produce more ejecta than equal mass systems with ejecta masses and kinetic
energies depending almost linearly on $q$. We estimate luminosity peaks and
light curves of macronovae events associated to the mergers using a simple
approach. For $q\sim2$ the luminosity peak is delayed for several days and can
be up to four times larger than for the $q=1$ cases. The macronova emission
associated with the $q\sim2$ BNS is more persistent in time and could be
observed for weeks instead of few days ($q=1$) in the near infrared. Finally,
we estimate the flux of possible radio flares produced by the interaction of
relativistic outflows with the surrounding medium. Also in this case a large
$q$ can significantly enhance the emission and delay the peak luminosity.
Overall, our results indicate that BNS merger with large mass ratio have EM
signatures distinct from the equal mass case and more similar to black hole -
neutron star binaries.


title: Constraints on dynamo action in plasmas

abstract:
  Upper bounds are derived on the amount of magnetic energy that can be
generated by dynamo action in collisional and collisionless plasmas with and
without external forcing. A hierarchy of mathematical descriptions is
considered for the plasma dynamics: ideal MHD, visco-resistive MHD, the
double-adiabatic theory of Chew, Goldberger and Low (CGL), kinetic MHD, and
other kinetic models. It is found that dynamo action is greatly constrained in
models where the magnetic moment of any particle species is conserved. In the
absence of external forcing, the magnetic energy then remains small at all
times if it is small in the initial state. In other words, a small "seed"
magnetic field cannot be amplified significantly, regardless of the nature of
flow, as long as the collision frequency and gyroradius are small enough to be
negligible. A similar conclusion also holds if the system is subject to
external forcing as long as this forcing conserves the magnetic moment of at
least one plasma species and does not greatly increase the total energy of the
plasma (i.e., in practice, is subsonic). Dynamo action therefore always
requires collisions or some small-scale kinetic mechanism for breaking the
adiabatic invariance of the magnetic moment.


title:
Elliptic equations involving the 1--Laplacian and a total variation term
  with $L^{N,\infty}$--data

abstract:
  In this paper we study, in an open bounded set $\Omega\subset\mathbb R^N$
with Lipschitz boundary $\partial\Omega$, the Dirichlet problem for a nonlinear
singular elliptic equation involving the $1$--Laplacian and a total variation
term, that is, the inhomogeneous case of the equation appearing in the level
set formulation of the inverse mean curvature flow. Our aim is twofold. On the
one hand, we consider data belonging to the Marcinkiewicz space
$L^{N,\infty}(\Omega)$, which leads to unbounded solutions. So, we have to
begin introducing the suitable notion of unbounded solution to this problem.
Moreover, examples of explicit solutions are shown. On the other hand, this
equation allows us to deal with many related problems having a different
gradient term. It is known that the total variation term induces a regularizing
effect on existence, uniqueness and regularity. We focus on analyzing whether
those features remain true when general gradient terms are taken. Roughly
speaking, the bigger $g$, the better the properties of the solution.


title: Vector lattices and $f$-algebras: the classical inequalities

abstract:
  We prove an identity for sesquilinear maps from the Cartesian square of a
vector space to a geometric mean closed Archimedean (real or complex) vector
lattice, from which the Cauchy-Schwarz inequality follows. A reformulation of
this result for sesquilinear maps with a geometric mean closed semiprime
Archimedean (real or complex) $f$-algebra as codomain is also given. In
addition, a sufficient and necessary condition for equality is presented. We
also prove the H\"older inequality for weighted geometric mean closed
Archimedean (real or complex) $\Phi$-algebras, improving results by Boulabiar
and Toumi. As a consequence, the Minkowski inequality for weighted geometric
mean closed Archimedean (real or complex) $\Phi$-algebras is obtained.


title:
Ephemeral protein binding to DNA shapes stable nuclear bodies and
  chromatin domains

abstract:
  Fluorescence microscopy reveals that the contents of many (membrane-free)
nuclear "bodies" exchange rapidly with the soluble pool whilst the underlying
structure persists; such observations await a satisfactory biophysical
explanation. To shed light on this, we perform large-scale Brownian dynamics
simulations of a chromatin fiber interacting with an ensemble of (multivalent)
DNA-binding proteins; these proteins switch between two states -- active
(binding) and inactive (non-binding). This system provides a model for any
DNA-binding protein that can be modified post-translationally to change its
affinity for DNA (e.g., like the phosphorylation of a transcription factor).
Due to this out-of-equilibrium process, proteins spontaneously assemble into
clusters of self-limiting size, as individual proteins in a cluster exchange
with the soluble pool with kinetics like those seen in photo-bleaching
experiments. This behavior contrasts sharply with that exhibited by
"equilibrium", or non-switching, proteins that exist only in the binding state;
when these bind to DNA non-specifically, they form clusters that grow
indefinitely in size. Our results point to post-translational modification of
chromatin-bridging proteins as a generic mechanism driving the self-assembly of
highly dynamic, non-equilibrium, protein clusters with the properties of
nuclear bodies. Such active modification also reshapes intra-chromatin contacts
to give networks resembling those seen in topologically-associating domains, as
switching markedly favors local (short-range) contacts over distant ones.

categories: physics.bio-ph cond-mat.soft cond-mat.stat-mech q-bio.SC


title: Optimal resampling for the noisy OneMax problem

abstract:
  The OneMax problem is a standard benchmark optimisation problem for a binary
search space. Recent work on applying a Bandit-Based Random Mutation
Hill-Climbing algorithm to the noisy OneMax Problem showed that it is important
to choose a good value for the resampling number to make a careful trade off
between taking more samples in order to reduce noise, and taking fewer samples
to reduce the total computational cost. This paper extends that observation, by
deriving an analytical expression for the running time of the RMHC algorithm
with resampling applied to the noisy OneMax problem, and showing both
theoretically and empirically that the optimal resampling number increases with
the number of dimensions in the search space.


title:
HRTF-based Robust Least-Squares Frequency-Invariant Polynomial
  Beamforming

abstract:
  In this work, we propose a robust Head-Related Transfer Function (HRTF)-based
polynomial beamformer design which accounts for the influence of a humanoid
robot's head on the sound field. In addition, it allows for a flexible steering
of our previously proposed robust HRTF-based beamformer design. We evaluate the
HRTF-based polynomial beamformer design and compare it to the original
HRTF-based beamformer design by means of signal-independent measures as well as
word error rates of an off-the-shelf speech recognition system. Our results
confirm the effectiveness of the polynomial beamformer design, which makes it a
promising approach to robust beamforming for robot audition.


title: Integrability of Orbifold ABJM Theories

abstract:
  Integrable structure has played a very important role in the study of various
non-perturbative aspects of planar ABJM theories. In this paper we showed that
this remarkable structure survive after orbifold operation with discrete group
$\Gamma(\simeq\mathbb{Z}_n)<SU(4)_R\times U(1)_b$. For general $\Gamma$, we
prove the integrability in the scalar sector at the planar two-loop order and
get the Bethe ansatz equations. The eigenvalues of the anomalous dimension
matrix are also obtained. For $\Gamma<SU(4)$, two-loop all-sector and all-loop
BAEs are proposed. Supersymmetric orbifolds are discussed in this framework.


title:
On the monotone stability approach to BSDEs with jumps: Extensions,
  concrete criteria and examples

abstract:
  We show a concise extension of the monotone stability approach to backward
stochastic differential equations (BSDEs) that are jointly driven by a Brownian
motion and a random measure for jumps, which could be of infinite activity with
a non-deterministic and time inhomogeneous compensator. The BSDE generator
function can be non convex and needs not to satisfy global Lipschitz conditions
in the jump integrand. We contribute concrete criteria, that are easy to
verify, for results on existence and uniqueness of bounded solutions to BSDEs
with jumps, and on comparison and a-priori $L^{\infty}$-bounds. Several
examples and counter examples are discussed to shed light on the scope and
applicability of different assumptions, and we provide an overview of major
applications in finance and optimal control.


title:
Characterization and performances of DOSION, a dosimetry equipment
  dedicated to radiobiology experiments taking place at GANIL

abstract:
  Currently, radiobiology experiments using heavy ions at GANIL(Grand
Accelerateur National d Ions Lourds) are conducted under the supervision of the
CIMAP (Center for research on Ions, MAterials and Photonics). In this context,
a new beam monitoring equipment named DOSION has been developed. It allows to
perform measurements of accurate fluence and dose maps in near real time for
each biological sample irradiated. In this paper, we present the detection
system, its design, performances, calibration protocol and measurements
performed during radiobiology experiments. This setup is currently available
for any radiobiology experiments if one wishes to correlate one s own sample
analysis to state of the art dosimetric references.


title:
Global weak solutions to the compressible quantum navier-stokes equation
  and its semi-classical limit

abstract:
  This paper is dedicated to the construction of global weak solutions to the
quantum Navier-Stokes equation, for any initial value with bounded energy and
entropy. The construction is uniform with respect to the Planck constant. This
allows to perform the semi-classical limit to the associated compressible
Navier-Stokes equation. One of the difficulty of the problem is to deal with
the degenerate viscosity, together with the lack of integrability on the
velocity. Our method is based on the construction of weak solutions that are
renormalized in the velocity variable. The existence, and stability of these
solutions do not need the Mellet-Vasseur inequality.


title: A factorization result for classical and similitude groups

abstract:
  For most classical and similitude groups, we show that each element can be
written as a product of two transformations that a) preserve or almost preserve
the underlying form and b) whose squares are certain scalar maps. This
generalizes work of Wonenburger and Vinroot. As an application, we re-prove and
slightly extend a well-known result of M{\oe}glin, Vign\'{e}ras and Waldspurger
on the existence of automorphisms of $p$-adic classical groups that take each
irreducible smooth representations to its dual.


title: A sharp estimate a la calderon-zygmund for the p--laplacian

abstract:
  We consider local weak solutions of the Poisson equation for the p--Laplace
operator. We prove a higher differentiability result, under an essentially
sharp condition on the right-hand side. The result comes with a local scaling
invariant a priori estimate.


title: The dynamics of quasiregular maps of punctured space

abstract:
  The Fatou-Julia iteration theory of rational and transcendental entire
functions has recently been extended to quasiregular maps in more than two real
dimensions. Our goal in this paper is similar; we extend the iteration theory
of analytic self-maps of the punctured plane to quasiregular self-maps of
punctured space.
  We define the Julia set as the set of points for which the complement of the
forward orbit of any neighbourhood of the point is a finite set. We show that
the Julia set is non-empty, and shares many properties with the classical Julia
set of an analytic function. These properties are stronger than those known to
hold for the Julia set of a general quasiregular map of space.
  We define the quasi-Fatou set as the complement of the Julia set, and
generalise a result of Baker concerning the topological properties of the
components of this set. A key tool in the proof of these results is a version
of the fast escaping set. We generalise various results of Marti-Pete
concerning this set, for example showing that the Julia set is equal to the
boundary of the fast escaping set.


title:
Reducibility of 1-d Schr\"odinger equation with time quasiperiodic
  unbounded perturbations, II

abstract:
  We study the Schr\"odinger equation on $\R$ with a potential behaving as
$x^{2l}$ at infinity, $l\in[1,+\infty)$ and with a small time quasiperiodic
perturbation. We prove that, if the perturbation belongs to a class of
unbounded symbols including smooth potentials and magnetic type terms with
controlled growth at infinity, then the system is reducible.


title: Analysis of Different Types of Regret in Continuous Noisy Optimization

abstract:
  The performance measure of an algorithm is a crucial part of its analysis.
The performance can be determined by the study on the convergence rate of the
algorithm in question. It is necessary to study some (hopefully convergent)
sequence that will measure how "good" is the approximated optimum compared to
the real optimum. The concept of Regret is widely used in the bandit literature
for assessing the performance of an algorithm. The same concept is also used in
the framework of optimization algorithms, sometimes under other names or
without a specific name. And the numerical evaluation of convergence rate of
noisy algorithms often involves approximations of regrets. We discuss here two
types of approximations of Simple Regret used in practice for the evaluation of
algorithms for noisy optimization. We use specific algorithms of different
nature and the noisy sphere function to show the following results. The
approximation of Simple Regret, termed here Approximate Simple Regret, used in
some optimization testbeds, fails to estimate the Simple Regret convergence
rate. We also discuss a recent new approximation of Simple Regret, that we term
Robust Simple Regret, and show its advantages and disadvantages.


title:
Optimal bilinear control of nonlinear stochastic Schr\"odinger equations
  driven by linear multiplicative noise

abstract:
  Here is investigated the bilinear optimal control problem of quantum
mechanical systems with final observation governed by a stochastic nonlinear
Schr\"odinger equation perturbed by a linear multiplicative Wiener process. The
existence of an open loop optimal control and first order Lagrange optimality
conditions are derived, via Skorohod's representation theorem, Ekeland's
variational principle and the existence for the linearized dual backward
stochastic equation. Moreover, our approach in particular applies to the
deterministic case.


title:
Existence and comparison results for an elliptic equation involving the
  $1$-Laplacian and $L^1$-data

abstract:
  This paper is devoted to analyse the Dirichlet problem for a nonlinear
elliptic equation involving the $1$--Laplacian and a total variation term, that
is, the inhomogeneous case of the equation arising in the level set formulation
of the inverse mean curvature flow. We study this problem in an open bounded
set with Lipschitz boundary.
  We prove an existence result and a comparison principle for non--negative
$L^1$--data. Moreover, we search the summability that the solution reaches when
more regular $L^p$--data, with $1<p<N$, are considered and we give evidence
that this summability is optimal.
  To prove these results, we apply the theory of
$L^\infty$--divergence--measure fields which goes back to Anzellotti (1983).
The main difficulties of the proofs come from the absence of a definition for
the pairing of a general $L^\infty$--divergence--measure field and the gradient
of an unbounded $BV$--function.


title:
$SU(2)$ Gauge Theory with Two Fundamental Flavours: Scalar and
  Pseudoscalar Spectrum

abstract:
  We investigate the scalar and pseudoscalar spectrum of the $SU(2)$ gauge
theory with $N_f=2$ flavours of fermions in the fundamental representation
using non perturbative lattice simulations. We provide first benchmark
estimates of the mass of the lightest $0(0^{+})$ ($\sigma$), $0(0^{-})$
($\eta'$) and $1(0^+)$ ($a_0$) states, including estimates of the relevant
disconnected contributions. We find $m_{a_0}/F_{\rm{PS}}= 16.7(4.9)$,
$m_\sigma/F_{\rm{PS}}=19.2(10.8)$ and $m_{\eta'}/F_{\rm{PS}} = 12.8(4.7)$.
These values for the masses of light scalar states provide crucial information
for composite extensions of the Standard Model from the unified Fundamental
Composi te Higgs-Technicolor theory \cite{Cacciapaglia:2014uja} to models of
composite dark matter.


title:
Geometry of Compact Metric Space in Terms of Gromov-Hausdorff Distances
  to Regular Simplexes

abstract:
  In the present paper we investigate geometric characteristics of compact
metric spaces, which can be described in terms of Gromov-Hausdorff distances to
simplexes, i.e., to finite metric spaces such that all their nonzero distances
are equal to each other. It turns out that these Gromov-Hausdorff distances
depend on some geometrical characteristics of finite partitions of the compact
metric spaces; some of the characteristics can be considered as a natural
analogue of the lengths of edges of minimum spanning trees. As a consequence,
we constructed an unexpected example of a continuum family of pairwise
non-isometric finite metric spaces with the same distances to all simplexes.


title:
Laser and cavity cooling of a mechanical resonator with a
  Nitrogen-Vacancy center in diamond

abstract:
  We theoretically analyse the cooling dynamics of a high-Q mode of a
mechanical resonator, when the structure is also an optical cavity and is
coupled with a NV center. The NV center is driven by a laser and interacts with
the cavity photon field and with the strain field of the mechanical oscillator,
while radiation pressure couples mechanical resonator and cavity field.
Starting from the full master equation we derive the rate equation for the
mechanical resonator's motion, whose coefficients depend on the system
parameters and on the noise sources. We then determine the cooling regime, the
cooling rate, the asymptotic temperatures, and the spectrum of resonance
fluorescence for experimentally relevant parameter regimes. For these
parameters, we consider an electronic transition, whose linewidth allows one to
perform sideband cooling, and show that the addition of an optical cavity in
general does not improve the cooling efficiency. We further show that pure
dephasing of the NV center's electronic transitions can lead to an improvement
of the cooling efficiency.


abstract:
  We propose a novel support vector regression approach called e-Distance
Weighted Support Vector Regression (e-DWSVR).e-DWSVR specifically addresses two
challenging issues in support vector regression: first, the process of noisy
data; second, how to deal with the situation when the distribution of boundary
data is different from that of the overall data. The proposed e-DWSVR optimizes
the minimum margin and the mean of functional margin simultaneously to tackle
these two issues. In addition, we use both dual coordinate descent (CD) and
averaged stochastic gradient descent (ASGD) strategies to make e-DWSVR scalable
to large scale problems. We report promising results obtained by e-DWSVR in
comparison with existing methods on several benchmark datasets.


title: Cloud Service Matchmaking using Constraint Programming

abstract:
  Service requesters with limited technical knowledge should be able to compare
services based on their quality of service (QoS) requirements in cloud service
marketplaces. Existing service matching approaches focus on QoS requirements as
discrete numeric values and intervals. The analysis of existing research on
non-functional properties reveals two improvement opportunities: list-typed QoS
properties as well as explicit handling of preferences for lower or higher
property values. We develop a concept and constraint models for a service
matcher which contributes to existing approaches by addressing these issues
using constraint solvers. The prototype uses an API at the standardisation
stage and discovers implementation challenges. This paper concludes that
constraint solvers provide a valuable tool to solve the service matching
problem with soft constraints and are capable of covering all QoS property
types in our analysis. Our approach is to be further investigated in the
application context of cloud federations.


title:
Investigations into Light-front Quartic Interactions for Massless Fields
  (I): Non-constructibility of Higher Spin Quartic Amplitudes

abstract:
  The dynamical commutators of the light-front Poincar\'e algebra yield first
order differential equations in the $p^+$ momenta for the interaction vertex
operators. The homogeneous solution to the equation for the quartic vertex is
studied. Consequences as regards the constructibility assumption of quartic
higher spin amplitudes from cubic amplitudes are discussed. The existence of
quartic contact interactions unrelated to cubic interactions by Poincar\'e
symmetry indicates that the higher spin S-matrix is not constructible. Thus
quartic amplitude based no-go results derived by BCFW recursion for Minkowski
higher spin massless fields may be circumvented.


title: Fast Longest Common Extensions in Small Space

abstract:
  In this paper we address the longest common extension (LCE) problem: to
compute the length $\ell$ of the longest common prefix between any two suffixes
of $T\in \Sigma^n$ with $ \Sigma = \{0, \ldots \sigma-1\} $. We present two
fast and space-efficient solutions based on (Karp-Rabin)
\textit{fingerprinting} and \textit{sampling}. Our first data structure
exploits properties of Mersenne prime numbers when used as moduli of the
Karp-Rabin hash function and takes $n\lceil \log_2\sigma\rceil$ bits of space.
Our second structure works with any prime modulus and takes $n\lceil
\log_2\sigma\rceil + n/w + w\log_2 n$ bits of space ($ w $ memory-word size).
Both structures support $\mathcal O\left(m\log\sigma/w \right)$-time extraction
of any length-$m$ text substring, $\mathcal O(\log\ell)$-time LCE queries with
high probability, and can be built in optimal $\mathcal O(n)$ time. In the
first case, ours is the first result showing that it is possible to answer LCE
queries in $o(n)$ time while using only $\mathcal O(1)$ words on top of the
space required to store the text. Our results improve the state of the art in
space usage, query times, and preprocessing times and are extremely practical:
we present a C++ implementation that is very fast and space-efficient in
practice.


title:
Moutard type transformation for matrix generalized analytic functions
  and gauge transformations

abstract:
  A Moutard type transformation for matrix generalized analytic functions is
derived. Relations between Moutard type transforms and gauge transformations
are demonstrated.


title:
Impact of nonlinear effective interactions on GFT quantum gravity
  condensates

abstract:
  We present the numerical analysis of effectively interacting Group Field
Theory (GFT) models in the context of the GFT quantum gravity condensate
analogue of the Gross-Pitaevskii equation for real Bose-Einstein condensates
including combinatorially local interaction terms. Thus we go beyond the
usually considered construction for free models.
  More precisely, considering such interactions in a weak regime, we find
solutions for which the expectation value of the number operator N is finite,
as in the free case. When tuning the interaction to the strongly nonlinear
regime, however, we obtain solutions for which N grows and eventually blows up,
which is reminiscent of what one observes for real Bose-Einstein condensates,
where a strong interaction regime can only be realized at high density. This
behaviour suggests the breakdown of the Bogoliubov ansatz for quantum gravity
condensates and the need for non-Fock representations to describe the system
when the condensate constituents are strongly correlated.
  Furthermore, we study the expectation values of certain geometric operators
imported from Loop Quantum Gravity in the free and interacting cases. In
particular, computing solutions around the nontrivial minima of the interaction
potentials, one finds, already in the weakly interacting case, a nonvanishing
condensate population for which the spectra are dominated by the lowest
nontrivial configuration of the quantum geometry. This result indicates that
the condensate may indeed consist of many smallest building blocks giving rise
to an effectively continuous geometry, thus suggesting the interpretation of
the condensate phase to correspond to a geometric phase.


title:
Critical behavior of charged black holes in Gauss-Bonnet gravity`s
  rainbow

abstract:
  Following an earlier study regarding Gauss-Bonnet-Maxwell black holes in the
presence of gravity's rainbow [S. H. Hendi and M. Faizal, Phys. Rev. D 92,
044027 (2015)], in this paper, we will consider all constants as energy
dependent ones. The geometrical and thermodynamical properties of this
generalization are studied and the validation of the first law of
thermodynamics is examined. Next, through the use of proportionality between
cosmological constant and thermodynamical pressure, van der Waals-like behavior
of these black holes in extended phase space is investigated. An interesting
critical behavior for sets of rainbow functions in this case is reported. Also,
the critical behavior of uncharged and charged solutions is analyzed and it is
shown that the generalization to a charged case puts an energy dependent
restriction on values of different parameters.


title:
A comparative study between EGB gravity and GTR by modelling compact
  stars

abstract:
  In this paper we utilise the Krori-Barua ansatz to model compact stars within
the framework of Einstein- Gauss-Bonnet (EGB) gravity. The thrust of our
investigation is to carry out a comparative analysis of the physical properties
of our models in EGB and classical general relativity theory.


title: Approximation Schemes for Geometric Coverage Problems

abstract:
  In their seminal work, Mustafa and Ray (2009) showed that a wide class of
geometric set cover (SC) problems admit a PTAS via local search -- this is one
of the most general approaches known for such problems. Their result applies if
a naturally defined "exchange graph" for two feasible solutions is planar and
is based on subdividing this graph via a planar separator theorem due to
Frederickson (1987). Obtaining similar results for the related maximum
k-coverage problem (MC) seems non-trivial due to the hard cardinality
constraint. In fact, while Badanidiyuru, Kleinberg, and Lee (2012) have shown
(via a different analysis) that local search yields a PTAS for two-dimensional
real halfspaces, they only conjectured that the same holds true for dimension
three. Interestingly, at this point it was already known that local search
provides a PTAS for the corresponding set cover case and this followed directly
from the approach of Mustafa and Ray.
  In this work we provide a way to address the above-mentioned issue. First, we
propose a color-balanced version of the planar separator theorem. The resulting
subdivision approximates locally in each part the global distribution of the
colors. Second, we show how this roughly balanced subdivision can be employed
in a more careful analysis to strictly obey the hard cardinality constraint.
More specifically, we obtain a PTAS for any "planarizable" instance of MC and
thus essentially for all cases where the corresponding SC instance can be
tackled via the approach of Mustafa and Ray. As a corollary, we confirm the
conjecture of Badanidiyuru, Kleinberg, and Lee regarding real half spaces in
dimension three. We feel that our ideas could also be helpful in other
geometric settings involving a cardinality constraint.


title: Gravity in the Quantum Lab

abstract:
  At the beginning of the previous century, Newtonian mechanics fell victim to
two new revolutionary theories, Quantum Mechanics (QM) and General Relativity
(GR). Both theories have transformed our view of physical phenomena, with QM
accurately predicting the results of experiments taking place at small length
scales, and GR correctly describing observations at larger length scales.
However, despite the impressive predictive power of each theory in their
respective regimes, their unification still remains unresolved. Theories and
proposals for their unification exist but we are lacking experimental guidance
towards the true unifying theory. Probing GR at small length scales where
quantum effects become relevant is particularly problematic but recently there
has been a growing interest in probing the opposite regime, QM at large scales
where relativistic effects are important. This is principally due to the fact
that experimental techniques in quantum physics have developed rapidly in
recent years with the promise of quantum technologies. Here we review recent
advances in experimental and theoretical work on quantum experiments that will
be able to probe relativistic effects of gravity on quantum properties, playing
particular attention to the role of Quantum Field Theory in Curved Spacetime
(QFTCS) in describing these experiments. Interestingly, theoretical work using
QFTCS has illustrated that these quantum experiments could be used to enhance
measurements of gravitational effects, such as Gravitational Waves (GWs).
Furthermore, verification of such enhancements, as well as other QFTCS
predictions in quantum experiments, would provide the first direct validation
of this limiting case of quantum gravity, several decades after it was
initially proposed.


title: Inpainting of long audio segments with similarity graphs

abstract:
  We present a novel method for the compensation of long duration data loss in
audio signals, in particular music. The concealment of such signal defects is
based on a graph that encodes signal structure in terms of time-persistent
spectral similarity. A suitable candidate segment for the substitution of the
lost content is proposed by an intuitive optimization scheme and smoothly
inserted into the gap, i.e. the lost or distorted signal region. Extensive
listening tests show that the proposed algorithm provides highly promising
results when applied to a variety of real-world music signals.


title:
Scaling properties of the number of random sequential adsorption
  iterations needed to generate saturated random packing

abstract:
  The properties of the number of iterations in random sequential adsorption
protocol needed to generate finite saturated random packing of spherically
symmetric shapes were studied. Numerical results obtained for one, two, and
three dimensional packings were supported by analytical calculations valid for
any dimension $d$. It has been shown that the number of iterations needed to
generate finite saturated packing is subject to Pareto distribution with
exponent $-1-1/d$ and the median of this distribution scales with packing size
according to the power-law characterized by exponent $d$. Obtained resultscan
be used in designing effective RSA simulations.


title: Multiwavelength and parsec-scale properties of extragalactic jets

abstract:
  Extragalactic jets originating from the central supermassive black holes of
active galaxies are powerful, highly relativistic plasma outflows, emitting
light from the radio up to the gamma-ray regime. The details of their
formation, composition and emission mechanisms are still not completely clear.
The combination of high-resolution observations using very long baseline
interferometry (VLBI) and multiwavelength monitoring provides the best insight
into these objects. Here, such a combined study of sources of the TANAMI sample
is presented, investigating the parsec-scale and high-energy properties. The
TANAMI program is a multiwavelength monitoring program of a sample of the radio
and gamma-ray brightest extragalactic jets in the southern sky, below -30deg
declination. We obtain the first-ever VLBI images for most of the sources,
providing crucial information on the jet kinematics and brightness distribution
at milliarcsecond resolution. Two particular sources are discussed in detail:
PMN J1603-4904, which can be classified either as an atypical blazar or a
gamma-ray loud (young) radio galaxy, and Centaurus A, the nearest radio-loud
active galaxy. The VLBI kinematics of the innermost parsec of Centaurus A's jet
result in a consistent picture of an accelerated jet flow with a spine-sheath
like structure.


title: Nonsingular black holes in Palatini extensions of General Relativity

abstract:
  An introduction to extended theories of gravity formulated in metric-affine
(or Palatini) spaces is presented. Focusing on spherically symmetric
configurations with electric fields, we will see that in these theories the
central singularity present in General Relativity is generically replaced by a
wormhole structure. The resulting space-time becomes geodesically complete and,
therefore, can be regarded as non-singular. We illustrate these properties
considering two different models, namely, a quadratic $f(R)$ theory and a
Born-Infeld like gravity theory.


title:
The Python user interface of the elsA cfd software: a coupling framework
  for external steering layers

abstract:
  The Python--elsA user interface of the elsA cfd (Computational Fluid
Dynamics) software has been developed to allow users to specify simulations
with confidence, through a global context of description objects grouped inside
scripts. The software main features are generated documentation, context
checking and completion, and helpful error management. Further developments
have used this foundation as a coupling framework, allowing (thanks to the
descriptive approach) the coupling of external algorithms with the cfd solver
in a simple and abstract way, leading to more success in complex simulations.
Along with the description of the technical part of the interface, we try to
gather the salient points pertaining to the psychological viewpoint of user
experience (ux). We point out the differences between user interfaces and pure
data management systems such as cgns.


title:
Joint eigenfunctions for the relativistic Calogero-Moser Hamiltonians of
  hyperbolic type. II. The two- and three-variable cases

abstract:
  In a previous paper we introduced and developed a recursive construction of
joint eigenfunctions $J_N(a_+,a_-,b;x,y)$ for the Hamiltonians of the
hyperbolic relativistic Calogero-Moser system with arbitrary particle number
$N$. In this paper we focus on the cases $N=2$ and $N=3$, and establish a
number of conjectured features of the corresponding joint eigenfunctions. More
specifically, choosing $a_+,a_-$ positive, we prove that $J_2(b;x,y)$ and
$J_3(b;x,y)$ extend to globally meromorphic functions that satisfy various
invariance properties as well as a duality relation. We also obtain detailed
information on the asymptotic behavior of similarity transformed functions
E$_2(b;x,y)$ and E$_3(b;x,y)$. In particular, we determine the dominant
asymptotics for $y_1-y_2\to\infty$ and $y_1-y_2,y_2-y_3\to\infty$, resp., from
which the conjectured factorized scattering can be read off.

categories: math-ph math.CA math.MP math.QA nlin.SI quant-ph


title: Magnetic diffuse scattering in artificial kagome spin ice

abstract:
  The study of magnetic correlations in dipolar-coupled nanomagnet systems with
synchrotron x-ray scattering provides a means to uncover emergent phenomena and
exotic phases, in particular in systems with thermally active magnetic moments.
From the diffuse signal of soft x-ray resonant magnetic scattering, we have
measured magnetic correlations in a highly dynamic artificial kagome spin ice
with sub-70-nm Permalloy nanomagnets. On comparing experimental scattering
patterns with Monte Carlo simulations based on a needle-dipole model, we
conclude that kagome ice I phase correlations exist in our experimental system
even in the presence of moment fluctuations, which is analogous to bulk spin
ice and spin liquid behavior. In addition, we describe the emergence of
quasi-pinch-points in the magnetic diffuse scattering in the kagome ice I
phase. These quasi-pinch-points bear similarities to the fully developed pinch
points with singularities of a magnetic Coulomb phase, and continually evolve
into the latter on lowering the temperature. The possibility to measure
magnetic diffuse scattering with soft x rays opens the way to study magnetic
correlations in a variety of nanomagnetic systems.


title: Cloud Service Matchmaking Approaches: A Systematic Literature Survey

abstract:
  Service matching concerns finding suitable services according to the service
requester's requirements, which is a complex task due to the increasing number
and diversity of cloud services available. Service matching is discussed in web
services composition and user oriented service marketplaces contexts. The
suggested approaches have different problem definitions and have to be examined
closer in order to identify comparable results and to find out which approaches
have built on the former ones. One of the most important use cases is service
requesters with limited technical knowledge who need to compare services based
on their QoS requirements in cloud service marketplaces. Our survey examines
the service matching approaches in order to find out the relation between their
context and their objectives. Moreover, it evaluates their applicability for
the cloud service marketplaces context.


title:
Hilbert space theory for relativistic dynamics with reflection. Special
  cases

abstract:
  We present and study a novel class of one-dimensional Hilbert space
eigenfunction transforms that diagonalize analytic difference operators
encoding the (reduced) two-particle relativistic hyperbolic Calogero-Moser
dynamics. The scattering is described by reflection and transmission amplitudes
$t$ and $r$ with function-theoretic features that are quite different from
nonrelativistic amplitudes. The axiomatic Hilbert space analysis in the
appendices is inspired by and applied to the attractive two-particle
relativistic Calogero-Moser dynamics for a sequence of special couplings.
Together with the scattering function $u$ of the repulsive case, this leads to
a triple of amplitudes $u, t, r$ satisfying the Yang-Baxter equations.


title:
Detection of surface defects on ceramic tiles based on morphological
  techniques

abstract:
  Ceramic tiles have become very popular and are used in the flooring of
offices and shopping malls. As testing the quality of tiles manually in a
highly polluted environment in the manufacturing industry is a labor-intensive
and time consuming process, analysis is carried out on the tile images. This
paper discusses an automated system to detect the defects on the surface of
ceramic tiles based on dilation, erosion, SMEE and boundary detection
techniques.


title:
Stability on the Inverse Random Source Scattering Problem for the
  One-Dimensional Helmholtz Equation

abstract:
  Consider the one-dimensional stochastic Helmholtz equation where the source
is assumed to be driven by the white noise. This paper concerns the stability
analysis of the inverse random source problem which is to reconstruct the
statistical properties of the source such as the mean and variance. Our results
show that increasing stability can be obtained for the inverse problem by using
suitable boundary data with multi-frequencies.


title:
Random Neighborhood Graphs as Models of Fracture Networks on Rocks:
  Structural and Dynamical Analysis

abstract:
  We propose a new model to account for the main structural characteristics of
rock fracture networks (RFNs). The model is based on a generalization of the
random neighborhood graphs to consider fractures embedded into rectangular
spaces. We study a series of 29 real-world RFNs and find the best fit with the
random rectangular neighborhood graphs (RRNGs) proposed here. We show that this
model captures most of the structural characteristics of the RFNs and allows a
distinction between small and more spherical rocks and large and more elongated
ones. We use a diffusion equation on the graphs in order to model diffusive
processes taking place through the channels of the RFNs. We find a small set of
structural parameters that highly correlates with the average diffusion time in
the RFNs. We found analytically some bounds for the diameter and the algebraic
connectivity of these graphs that allow to bound the diffusion time in these
networks. We also show that the RRNGs can be used as a suitable model to
replace the RFNs in the study of diffusion-like processes. Indeed, the
diffusion time in RFNs can be predicted by using structural and dynamical
parameters of the RRNGs. Finally, we also explore some potential extensions of
our model to include variable fracture apertures, the possibility of long-range
hops of the diffusive particles as a way to account for heterogeneities in the
medium and possible superdiffusive processes, and the extension of the model to
3-dimensional space.


title: Discrete Unitary Invariance

abstract:
  We show that certain determinantal functions of multiple matrices, when
summed over the symmetries of the cube, decompose into functions of the
original matrices. These are shown to be true in complete generality; that is,
no properties of the underlying vector space will be used apart from normal
ring properties, and therefore hold in any commutative ring. All proofs are
elementary --- in fact, the majority are simply derivations.


title: Towards the next generation of simplified Dark Matter models

abstract:
  This White Paper is an input to the ongoing discussion about the extension
and refinement of simplified Dark Matter (DM) models. Based on two concrete
examples, we show how existing simplified DM models (SDMM) can be extended to
provide a more accurate and comprehensive framework to interpret and
characterise collider searches. In the first example we extend the canonical
SDMM with a scalar mediator to include mixing with the Higgs boson. We show
that this approach not only provides a better description of the underlying
kinematic properties that a complete model would possess, but also offers the
option of using this more realistic class of scalar mixing models to compare
and combine consistently searches based on different experimental signatures.
The second example outlines how a new physics signal observed in a visible
channel can be connected to DM by extending a simplified model including
effective couplings. This discovery scenario uses the recently observed excess
in the high-mass diphoton searches of ATLAS and CMS for a case study to show
that such a pragmatic approach can aid the experimental search programme to
verify/falsify a potential signal and to study its underlying nature. In the
next part of the White Paper we outline other interesting options for SDMM that
could be studied in more detail in the future. Finally, we discuss important
aspects of supersymmetric models for DM and how these could help to develop of
more complete SDMM.


title: Sum of two repdigits a square

abstract:
  A \emph{repdigit} is a natural number greater than 10 which has all of its
base-10 digits the same. In this paper we find all examples of two repdigits
adding to a square. The proofs lead to interesting questions about consecutive
quadratic residues and non-residues, and provide an elementary application of
elliptic curves.


title: Optical Spectroscopy of Comet C/2014 Q2 (Lovejoy) from MIRO

abstract:
  Spectra of comet C/2014 Q2 (Lovejoy) were taken with a low resolution
spectrograph mounted on the 0.5 m telescope at the Mount Abu Infrared
Observatory (MIRO), India during January to May 2015 covering the perihelion
and post-perihelion periods. The spectra showed strong molecular emission bands
(C2, C3 and CN) in January, close to perihelion. We have obtained the scale
lengths for these molecules by fitting the Haser model to the observed column
densities. The variation of gas production rates and production rate ratios
with heliocentric distance were studied. The extent of the dust continuum using
the Af-rho parameter and its variation with the heliocentric distance were also
investigated. The comet is seen to become more active in the post-perihelion
phase, thereby showing an asymmetric behaviour about the perihelion.


title:
Identification of a membrane-bound prepore species clarifies the lytic
  mechanism of actinoporins

abstract:
  Pore-forming toxins (PFT) are cytolytic proteins belonging to the molecular
warfare apparatus of living organisms. The assembly of the functional
transmembrane pore requires several intermediate steps ranging from a
water-soluble monomeric species to the multimeric ensemble inserted in the cell
membrane. The non-lytic oligomeric intermediate known as prepore plays an
essential role in the mechanism of insertion of the class of $\beta$-PFT.
However, in the class of $\alpha$-PFT like the actinoporins produced by sea
anemones, evidence of membrane-bound prepores is still lacking. We have
employed single-particle cryo-electron microscopy (cryo-EM) and atomic force
microscopy (AFM) to identify, for the first time, a prepore species of the
actinoporin fragaceatoxin C (FraC) bound to lipid vesicles. The size of the
prepore coincides that of the functional pore, except for the transmembrane
region, which is absent in the prepore. Biochemical assays indicated that, in
the prepore species, the N-terminus is not inserted in the bilayer but exposed
to the aqueous solution. Our study reveals the structure of the prepore complex
in actinoporins, and highlights the role of structural intermediates for the
formation of cytolytic pores by an $\alpha$-PFT.


title:
Transition Region and Chromospheric Signatures of Impulsive Heating
  Events. II. Modeling

abstract:
  Results from the Solar Maximum Mission showed a close connection between the
hard X-ray and transition region emission in solar flares. Analogously, the
modern combination of RHESSI and IRIS data can inform the details of heating
processes in ways never before possible. We study a small event that was
observed with RHESSI, IRIS, SDO, and Hinode, allowing us to strongly constrain
the heating and hydrodynamical properties of the flare, with detailed
observations presented in a previous paper. Long duration red-shifts of
transition region lines observed in this event, as well as many other events,
are fundamentally incompatible with chromospheric condensation on a single
loop. We combine RHESSI and IRIS data to measure the energy partition among the
many magnetic strands that comprise the flare. Using that observationally
determined energy partition, we show that a proper multi-threaded model can
reproduce these red-shifts in magnitude, duration, and line intensity, while
simultaneously being well constrained by the observed density, temperature, and
emission measure. We comment on the implications for both RHESSI and IRIS
observations of flares in general, namely that: (1) a single loop model is
inconsistent with long duration red-shifts, among other observables; (2) the
average time between energization of strands is less than 10 seconds, which
implies that for a hard X-ray burst lasting ten minutes, there were at least 60
strands within a single IRIS pixel located on the flare ribbon; (3) the
majority of these strands were explosively heated with energy distribution well
described by a power law of slope $\approx -1.6$; (4) the multi-stranded model
reproduces the observed line profiles, peak temperatures, differential emission
measure distributions, and densities.


title: Structured network regression for spatial point patterns

abstract:
  The analysis of spatial point patterns that occur in the network domain have
recently gained much attraction and various intensity functions and measures
have been proposed. However, the linkage of spatial network statistics to
regression models has not been approached so far. This paper presents a new
regression approach which treats a generic intensity function of a planar point
pattern that occurred on a network as the outcome of a set of different
covariates and various graph statistics. Different to all alternative
approaches, our model is the first which permits the statistical analysis of
complex regression data in the context of network intensity functions for
spatial point patterns. The potential of our new technique to model the
structural dependencies of network intensity functions on various covariates
and graph statistics is illustrated using call-in data on neighbour and
community disturbances in an urban context.


title:
The analemma criterion: accidental quasi-satellites are indeed true
  quasi-satellites

abstract:
  In the Solar system, a quasi-satellite is an object that follows a
heliocentric path with an orbital period that matches almost exactly with that
of a host body (planetary or not). The trajectory is of such nature that,
without being gravitationally attached, the value of the angular separation
between host and quasi-satellite as seen from the Sun remains confined within
relatively narrow limits for time-spans that exceed the length of the host's
sidereal orbital period. Here, we show that under these conditions, a
quasi-satellite traces an analemma in the sky as observed from the host in a
manner similar to that found for geosynchronous orbits. The analemmatic curve
(figure-eight-, teardrop-, ellipse-shaped) results from the interplay between
the tilt of the rotational axis of the host and the properties of the orbit of
the quasi-satellite. The analemma criterion can be applied to identify true
quasi-satellite dynamical behaviour using observational or synthetic astrometry
and it is tested for several well-documented quasi-satellites. For the
particular case of 15810 (1994 JR1), a putative accidental quasi-satellite of
dwarf planet Pluto, we show explicitly that this object describes a complex
analemmatic curve for several Plutonian sidereal periods, confirming its
transient quasi-satellite status.


title:
A way to measure the water quality of the LHAASO-WCDA with cosmic muon
  signals

abstract:
  The Large High Altitude Air Shower Observatory (LHAASO) is to be built at
Daocheng, Sichuan Province, China. As one of the major components of the LHAASO
project, a Water Cherenkov Detector Array (WCDA), with an area of 78,000~$\rm
m^{2}$, contains 350,000~tons of purified water. The water transparency and its
stability are critical for successful long-term operation of this project. To
gain full knowledge of the water Cherenkov technique and investigate the
engineering issues, a 9-cell detector array has been built at the Yangbajing
site, Tibet, China. With the help of the distribution of single cosmic muon
signals, the monitoring and measurement of water transparency are studied. The
results show that a precision of several percent can be obtained for the
attenuation length measurement, which satisfies the requirements of the
experiment. In the near future, this method could be applied to the LHAASO-WCDA
project.


title:
CYCLONE Unified Deployment and Management of Federated, Multi-Cloud
  Applications

abstract:
  Various Cloud layers have to work in concert in order to manage and deploy
complex multi-cloud applications, executing sophisticated workflows for Cloud
resource deployment, activation, adjustment, interaction, and monitoring. While
there are ample solutions for managing individual Cloud aspects (e.g. network
controllers, deployment tools, and application security software), there are no
well-integrated suites for managing an entire multi cloud environment with
multiple providers and deployment models. This paper presents the CYCLONE
architecture that integrates a number of existing solutions to create an open,
unified, holistic Cloud management platform for multi-cloud applications,
tailored to the needs of research organizations and SMEs. It discusses major
challenges in providing a network and security infrastructure for the
Intercloud and concludes with the demonstration how the architecture is
implemented in a real life bioinformatics use case.


title: From second grade fluids to the Navier-Stokes equations

abstract:
  We consider the limit $\alpha\to0$ for a second grade fluid on a bounded
domain with Dirichlet boundary conditions. We show convergence towards a
solution of the Navier-Stokes equations under two different types of hypothesis
on the initial velocity $u_0$. If the product $\|u_0\|_{L^2}\|u_0\|_{H^1}$ is
sufficiently small we prove global-in-time convergence. If there is no
smallness assumption we obtain local-in-time convergence up to the time
$C/\|u_0\|_{H^1}^4$.


title:
Comment on "Spin-Orbit Logic with Magnetoelectric Nodes: A Scalable
  Charge Mediated Nonvolatile Spintronic Logic" (arXiv:1512.05428)

abstract:
  Researchers from Intel Corporation recently proposed "Magneto-Electric Spin
Orbit (MESO)" logic as a new strategy for beyond-CMOS electronics [1]. The
Intel researchers project that this concept has the potential to reduce the
switching energy per bit "to near thermodynamic limits for GHz logic (100 kT
switching at 100 ps delay)", i.e., to near 0.4 aJ. Here I point out that the
switching energy stated in ref. [1] is incorrect, because the paper neglects a
large energy cost associated with Ohmic dissipation that is unavoidable within
the MESO scheme. Using optimistic parameters, the true minimum switching energy
per bit within the MESO approach is at least 150 fJ, or more than 300,000 times
greater than the value stated in ref. [1]. Given this large energy cost, the
MESO concept is not a viable strategy for beyond-CMOS logic.


title: Maxwell Matters

abstract:
  Charges are everywhere because most atoms are charged. Chemical bonds are
formed by electrons with their charge. Charges move and interact according to
Maxwell's equations in space and in atoms where the equations of
electrodynamics are embedded in Schroedinger's equation as the potential.
Maxwell's equations are universal, valid inside atoms and between stars from
times much shorter than those of atomic motion (0.1 femtoseconds) to years (32
mega-seconds). Maxwell's equations enforce the conservation of current.
Analysis shows that the electric field can take on whatever value is needed to
ensure conservation of current. The properties of matter rearrange themselves
to satisfy Maxwell's equations and conservation of current. Conservation of
current is as universal as Maxwell's equations themselves. Yet equations of
electrodynamics find little place in the literature of material physics,
chemistry, or biochemistry. Kinetic models of chemistry and Markov treatments
of atomic motion are ordinary differential equations in time and do not satisfy
conservation of current unless modified significantly. Systems at equilibrium,
without macroscopic flow, have thermal fluctuating currents that are conserved
according to the Maxwell equations although their macroscopic averages are
zero. The macroscopic consequences of atomic scale fluctuating thermal currents
are not known but are likely to be substantial because of the nonlinear
interactions in systems like these, in which 'everything interacts with
everything else'.
  Conclusion: current needs to be conserved in models of material systems, even
in simplified versions.