title: Rational orbits of the space of pairs of exceptional Jordan algebras

abstract:
  Let $k$ be a field of characteristic not equal to $2,3$, $\mathbb{O}$ an
octonion over $k$ and $\mathcal{J}$ the exceptional Jordan algebra defined by
$\mathbb{O}$. We consider the prehomogeneous vector space $(G,V)$ where
$G=GE_6\times \mathrm{GL}(2)$ and $V=\mathcal{J}\oplus \mathcal{J}$. We prove
that generic rational orbits of this prehomogeneous vector space are in
bijective correspondence with $k$-isomorphism classes of pairs
$(\mathcal{M},\mathfrak{n})$ where $\mathcal{M}$'s are isotopes of
$\mathcal{J}$ and $\mathfrak{n}$'s are cubic \'etale subalgebras of
$\mathcal{M}$. Also we prove that if $\mathbb{O}$ is split, then generic
rational orbits are in bijective correspondence with isomorphism classes of
separable extensions of $k$ of degrees up to $3$.


title: A note on distinct distances

abstract:
  We show that, for a constant-degree algebraic curve $\gamma$ in
$\mathbb{R}^D$, every set of $n$ points on $\gamma$ spans at least
$\Omega(n^{4/3})$ distinct distances, unless $\gamma$ is an {\it algebraic
helix} (see Definition 1.1). This improves the earlier bound $\Omega(n^{5/4})$
of Charalambides [Discrete Comput. Geom. (2014)].
  We also show that, for every set $P$ of $n$ points that lie on a
$d$-dimensional constant-degree algebraic variety $V$ in $\mathbb{R}^D$, there
exists a subset $S\subset P$ of size at least
$\Omega(n^{\frac{4}{9+12(d-1)}})$, such that $S$ spans $\binom{|S|}{2}$
distinct distances. This improves the earlier bound of
$\Omega(n^{\frac{1}{3d}})$ of Conlon et al. [SIAM J. Discrete Math. (2015)].
  Both results are consequences of a common technical tool, given in Lemma 2.7
below.


title:
Linear properties of Banach spaces and low distortion embeddings of
  metric graphs

abstract:
  We characterize non-reflexive Banach spaces by a low-distortion (resp.
isometric) embeddability of a certain metric graph up to a renorming. Also we
study non-linear sufficient conditions for $\ell_1^n$ being
$(1+\varepsilon)$-isomorphic to a subspace of a Banach space $X$.


title:
Categorical actions on unipotent representations of finite classical
  groups

abstract:
  We review the categorical representation of a Kac-Moody algebra on unipotent
representations of finite unitary groups in non-defining characteristic given
by the authors. Then, we extend this construction to finite reductive groups of
types B or C, in non-defining characteristic. We show that the decategorified
representation is isomorphic to a direct sum of level 2 Fock spaces. We deduce
that the Harish-Chandra branching graph coincides with the crystal graph of
these Fock spaces. We also obtain derived equivalences between blocks, yielding
Broue's abelian defect group conjecture for unipotent l-blocks at linear
primes.


title: On the density of cyclotomic lattices constructed from codes

abstract:
  Recently, Venkatesh improved the best known lower bound for lattice sphere
packings by a factor $\log\log n$ for infinitely many dimensions $n$. Here we
prove an effective version of this result, in the sense that we exhibit, for
the same set of dimensions, finite families of lattices containing a lattice
reaching this bound. Our construction uses codes over cyclotomic fields, lifted
to lattices via Construction A.


title: Suzaku observations of the 2013 outburst of KS 1947+300

abstract:
  We report on the timing and spectral analysis of two Suzaku observations with
different flux levels of the high-mass X-ray binary KS 1947+300 during its 2013
outburst. In agreement with simultaneous NuSTAR observations, the continuum is
well described by an absorbed power law with a cut-off and an additional black
body component. In addition we find fluorescent emission from neutral, He-like,
and even H-like iron. We determine a pulse period of ~18.8 s with the source
showing a spin-up between the two observations. Both Suzaku observations show a
very similar behavior of the pulse profile, which is strongly energy dependent,
with an evolution from a profile with one peak at low energies to a profile
with two peaks of different widths towards higher energies seen in both, the
Suzaku and NuSTAR data. Such an evolution to a more complex profile at higher
energies is rarely seen in X-ray pulsars, most cases show the opposite
behavior. Pulse phase-resolved spectral analysis shows a variation in the
absorbing column density, NH , over pulse phase. Spectra taken during the pulse
profile minima are intrinsically softer compared to the pulse phase-averaged
spectrum.


title:
Electronic structure of atomic manganese chains supported on Cu$_2$N /
  Cu (100)

abstract:
  Scanning tunnelling microscopy and density functional theory studies of
manganese chains adsorbed on Cu$_2$N/Cu (100) reveal an unsuspected electronic
edge state at $\sim 1$ eV above the Fermi energy. This Tamm-like state is
strongly localised to the last Mn atom of the chain and fully spin polarised.
However, no equivalence is found for occupied states, and the electronic
structure at $\sim -1$ eV is mainly spin unpolarised due to the extended
$p$-states of the N atoms that mediate the coupling between the Mn atoms in the
chain. Odd-numbered Mn chains present an exponentially decreasing direct
coupling with distance between the two edges, leading to a vanishing
bonding/anti-bonding splitting of states while even-numbered Mn chains present
perfect decoupling of both edges due to the the antiferromagnetic ordering of
Mn chains.


title:
Procedure to Approximately Estimate the Uncertainty of Material Ratio
  Parameters due to Inhomogeneity of Surface Roughness

abstract:
  Roughness parameters that characterize contacting surfaces with regard to
friction and wear are commonly stated without uncertainties, or with an
uncertainty only taking into account a very limited amount of aspects such as
repeatability of reproducibility (homogeneity) of the specimen. This makes it
difficult to discriminate between different values of single roughness
parameters.
  Therefore uncertainty assessment methods are required that take all relevant
aspects into account. In the literature this is scarcely performed and examples
specific for parameters used in friction and wear are not yet given.
  We propose a procedure to derive the uncertainty from a single profile
employing a statistical method that is based on the statistical moments of the
amplitude distribution and the autocorrelation length of the profile. To show
the possibilities and the limitations of this method we compare the uncertainty
derived from a single profile with that derived from a high statistics
experiment.


title: RowHammer: Reliability Analysis and Security Implications

abstract:
  As process technology scales down to smaller dimensions, DRAM chips become
more vulnerable to disturbance, a phenomenon in which different DRAM cells
interfere with each other's operation. For the first time in academic
literature, our ISCA paper exposes the existence of disturbance errors in
commodity DRAM chips that are sold and used today. We show that repeatedly
reading from the same address could corrupt data in nearby addresses. More
specifically: When a DRAM row is opened (i.e., activated) and closed (i.e.,
precharged) repeatedly (i.e., hammered), it can induce disturbance errors in
adjacent DRAM rows. This failure mode is popularly called RowHammer. We tested
129 DRAM modules manufactured within the past six years (2008-2014) and found
110 of them to exhibit RowHammer disturbance errors, the earliest of which
dates back to 2010. In particular, all modules from the past two years
(2012-2013) were vulnerable, which implies that the errors are a recent
phenomenon affecting more advanced generations of process technology.
Importantly, disturbance errors pose an easily-exploitable security threat
since they are a breach of memory protection, wherein accesses to one page
(mapped to one row) modifies the data stored in another page (mapped to an
adjacent row).


title: Continuous Deep Q-Learning with Model-based Acceleration

abstract:
  Model-free reinforcement learning has been successfully applied to a range of
challenging problems, and has recently been extended to handle large neural
network policies and value functions. However, the sample complexity of
model-free algorithms, particularly when using high-dimensional function
approximators, tends to limit their applicability to physical systems. In this
paper, we explore algorithms and representations to reduce the sample
complexity of deep reinforcement learning for continuous control tasks. We
propose two complementary techniques for improving the efficiency of such
algorithms. First, we derive a continuous variant of the Q-learning algorithm,
which we call normalized adantage functions (NAF), as an alternative to the
more commonly used policy gradient and actor-critic methods. NAF representation
allows us to apply Q-learning with experience replay to continuous tasks, and
substantially improves performance on a set of simulated robotic control tasks.
To further improve the efficiency of our approach, we explore the use of
learned models for accelerating model-free reinforcement learning. We show that
iteratively refitted local linear models are especially effective for this, and
demonstrate substantially faster learning on domains where such models are
applicable.


title: Non-additive Security Games

abstract: We have investigated the security game under non-additive utility functions.


title: Cool quark matter

abstract:
  We generalize the state-of-the-art perturbative Equation of State of cold
quark matter to nonzero temperatures, needed in the description of neutron star
mergers and core collapse processes. The new result is accurate to order g^5 in
the gauge coupling, and is based on a novel framework for dealing with the
infrared sensitive soft field modes of the theory. The zero Matsubara mode
sector is treated using a dimensionally reduced effective theory, while the
soft non-zero modes are resummed using the Hard Thermal Loop approximation.
This combination of known effective descriptions offers unprecedented access to
small but nonzero temperatures, both in and out of beta equilibrium.


title:
Equity forecast: Predicting long term stock price movement using machine
  learning

abstract:
  Long term investment is one of the major investment strategies. However,
calculating intrinsic value of some company and evaluating shares for long term
investment is not easy, since analyst have to care about a large number of
financial indicators and evaluate them in a right manner. So far, little help
in predicting the direction of the company value over the longer period of time
has been provided from the machines. In this paper we present a machine
learning aided approach to evaluate the equity's future price over the long
time. Our method is able to correctly predict whether some company's value will
be 10% higher or not over the period of one year in 76.5% of cases.


title: The Laura++ Dalitz plot fitter

abstract:
  The Laura++ software package is designed for performing fits of amplitude
models to data from decays of spin-0 particles into final states containing
three spin-0 particles - so-called Dalitz-plot analysis. An overview of the
amplitude formalism and its software implementation is given as well as
summaries of recently added features and planned future developments.


title:
On equivariant maps related to the space of pairs of exceptional Jordan
  algebras

abstract:
  Let $\mathcal{J}$ be the exceptional Jordan algebra and $V=\mathcal{J}\oplus
\mathcal{J}$. We construct an equivariant map from $V$ to
$\mathrm{Hom}_k(\mathcal{J}\otimes \mathcal{J},\mathcal{J})$ defined by
homogeneous polynomials of degree $8$ such that if $x\in V$ is a generic point,
then the image of $x$ is the structure constant of the isotope of $\mathcal{J}$
corresponding to $x$. We also give an alternative way to define the isotope
corresponding to a generic point of $\mathcal{J}$ by an equivariant map from
$\mathcal{J}$ to the space of trilinear forms.


title: Matrix Characterization of Multidimensional Subshifts of Finite Type

abstract:
  Let $X\subset A^{Z^d}$ be a $2$-dimensional subshift of finite type. We prove
that any $2$-dimensional multidimensional subshift of finite type can be
characterized by a square matrix of infinite dimension. We extend our result to
a general $d$-dimensional case. We prove that the multidimensional shift space
is non-empty if and only if the matrix obtained is of positive dimension. In
the process, we give an alternative view of the necessary and sufficient
conditions obtained for the non-emptiness of the multidimensional shift space.
We also give sufficient conditions for the shift space $X$ to exhibit periodic
points.


title:
Incommensurate--commensurate transitions in the mono-axial chiral
  helimagnet driven by the magnetic field

abstract:
  The zero temperature phase diagram of the mono-axial chiral helimagnet in the
magnetic field plane formed by the components parallel and perpendicular to the
helical axis is thoroughly analyzed. The nature of the transition to the
commensurate state depends on the angle between the field and the helical axis.
For field directions close to the directions parallel or perpendicular to the
helical axis the transition is continuous, while for intermediate angles the
transition is discontinuous and the incommensurate and commensurate states
coexist on the transition line. The continuous and discontinuous transition
lines are separated by two tricritical points with specific singular behaviour.
The location of the continuous and discontinuous lines and of the tricritical
points depend strongly on the easy-plane anisotropy, the effect of which is
analyzed. For large anisotropy the conical approximation locates the transition
line very accurately, although it does not predict the continuous transitions
nor the tricitical behaviour. It is shown that for large anisotropy, as in
CrNb3S6, the form of the transition line is universal, that is, independent of
the sample, and obeys a simple equation. The position of the tricritical
points, which is not universal, is theoretically estimated for a sample of
CrNb3S6


title:
Snapping elastic curves as a one-dimensional analogue of two-component
  lipid bilayers

abstract:
  In order to study a one-dimensional analogue of the spontaneous curvature
model for two-component lipid bilayer membranes we consider planar curves that
are made of a material with two phases. Each phase induces a preferred
curvature to the curve, and these curvatures as well as phase boundaries may
lead to the development of kinks. We introduce a family of energies for smooth
curves and phase fields, and we show that these energies $\Gamma$-converge to
an energy for curves with a finite number of kinks. The theoretical result is
illustrated by some numerical examples.


title: Giant Frictional Drag in Double Bilayer Graphene Heterostructures

abstract:
  We study the frictional drag between carriers in two bilayer graphene flakes
separated by a 2 $-$ 5 nm thick hexagonal boron nitride dielectric. At
temperatures ($T$) lower than $\sim$ 10 K, we observe a large anomalous
negative drag emerging predominantly near the drag layer charge neutrality. The
anomalous drag resistivity increases dramatically with reducing {\it T}, and
becomes comparable to the layer resistivity at the lowest {\it T} = 1.5 K. At
low $T$ the drag resistivity exhibits a breakdown of layer reciprocity. A
comparison of the drag resistivity and the drag layer Peltier coefficient
suggests a thermoelectric origin of this anomalous drag.


title:
Dissipation and decoherence effects on a moving particle in front of a
  dielectric plate

abstract:
  On this work, we consider a particle moving in front of a dielectric plate,
and study two of the most relevant effects of the vacuum field fluctuations:
the dissipation, and the decoherence of the particle's internal degrees of
freedom. We consider the particle to follow a classical, macroscopically-fixed
trajectory. To study the dissipative effects, we calculate the in-out effective
action by functionally integrating over the vacuum field and the microscopic
degrees of freedom of both the plate and the particle. This in-out effective
action develops an imaginary part, hence a non-vanishing probability for the
decay (because of friction) of the initial vacuum state. We analyze how the
dissipation is affected by the relative velocity between the particle and the
plate and the properties of the microscopic degrees of freedom. In order to
study the effects of decoherence over the internal degrees of freedom of the
particle, we calculate the CTP or Schwinger-Keldysh influence action, by
functionally integrating over the vacuum field and the microscopic degrees of
freedom of the plate. We estimate the decoherence time as the time needed by
two different quantum configurations (of the internal degree of freedom of the
particle) to be possible to differentiate from one another. We analyze the way
in which the presence of the mirror affects the decoherence, and the possible
ways to maximize or reduce its effects.


title: BPTree: an $\ell_2$ heavy hitters algorithm using constant memory

abstract:
  The task of finding heavy hitters is one of the best known and well studied
problems in the area of data streams. One is given a list
$i_1,i_2,\ldots,i_m\in[n]$ and the goal is to identify the items among $[n]$
that appear frequently in the list. In sub-polynomial space, the strongest
guarantee available is the $\ell_2$ guarantee, which requires finding all items
that occur at least $\epsilon\|f\|_2$ times in the stream, where the vector
$f\in\mathbb{R}^n$ is the count histogram of the stream with $i$th coordinate
equal to the number of times~$i$ appears $f_i:=\#\{j\in[m]:i_j=i\}$. The first
algorithm to achieve the $\ell_2$ guarantee was the CountSketch of [CCF04],
which requires $O(\epsilon^{-2}\log n)$ words of memory and $O(\log n)$ update
time and is known to be space-optimal if the stream allows for deletions. The
recent work of [BCIW16] gave an improved algorithm for insertion-only streams,
using only $O(\epsilon^{-2}\log\epsilon^{-1}\log\log n)$ words of memory. In
this work, we give an algorithm \bptree for $\ell_2$ heavy hitters in
insertion-only streams that achieves $O(\epsilon^{-2}\log\epsilon^{-1})$ words
of memory and $O(\log\epsilon^{-1})$ update time, which is the optimal
dependence on $n$ and $m$. In addition, we describe an algorithm for tracking
$\|f\|_2$ at all times with $O(\epsilon^{-2})$ memory and update time. Our
analyses rely on bounding the expected supremum of a Bernoulli process
involving Rademachers with limited independence, which we accomplish via a
Dudley-like chaining argument that may have applications elsewhere.


title:
The number of rational points on a family of varieties over finite
  fields

abstract:
  Let $\mathbb{F}_q$ stand for the finite field of odd characteristic $p$ with
$q$ elements ($q=p^{n},n\in \mathbb{N} $) and $\mathbb{F}_q^*$ denote the set
of all the nonzero elements of $\mathbb{F}_{q}$. Let $m$ and $t$ be positive
integers. In this paper, by using the Smith normal form of the exponent matrix,
we obtain a formula for the number of rational points on the variety defined by
the following system of equations over $\mathbb{F}_{q}$: $$
\sum\limits_{j=0}^{t-1}\sum\limits_{i=1}^{r_{j+1}-r_j}
a_{k,r_j+i}x_1^{e^{(k)}_{r_j+i,1}}...x_{n_{j+1}}^{e^{(k)}_{r_j+i,n_{j+1}}}=b_k,
\ k=1,...,m. $$ where the integers $t>0$, $r_0=0<r_1<r_2<...<r_t$, $1\le
n_1<n_2<...<n_t$, $0\leq j\leq t-1$, $b_k\in \mathbb{F}_{q}$, $a_{k,i}\in
\mathbb{F}_{q}^{*}$, $(k=1,...,m, i=1,...,r_t)$, and the exponent of each
variable is a positive integer. Furthermore, under some natural conditions, we
arrive at an explicit formula for the number of the above variety. It extends
the results obtained previously by Wolfmann, Sun, Wang, Song, Chen, Hong, Hu
and Zhao et al. Our result also answers completely an open problem raised by
Song and Chen.


title: Photofocusing: Light and flow of phototactic microswimmer suspension

abstract:
  We explore in this paper the phenomenon of photofocusing: a coupling between
flow vorticity and biased swimming of microalgae toward a light source that
produces a focusing of the microswimmer suspension. We combine experiments that
investigate the stationary state of this phenomenon as well as the transition
regime with analytical and numerical modeling. We show that the experimentally
observed scalings on the width of the focalized region and the establishment
length as a function of the flow velocity are well described by a simple
theoretical model.


title: On self-dual double circulant codes

abstract:
  Self-dual double circulant codes of odd dimension are shown to be dihedral in
even characteristic and consta-dihedral in odd characteristic. Exact counting
formulae are derived for them and used to show they contain families of codes
with relative distance satisfying a modified Gilbert-Varshamov bound.


title:
An algorithm for computing the reduction of $2$-dimensional crystalline
  representations of $\text{Gal}(\overline{\mathbf{Q}}_p/\mathbf{Q}_p)$

abstract:
  We describe an algorithm to compute the reduction modulo $p$ of a crystalline
Galois representation of dimension $2$ of
$\text{Gal}(\overline{\mathbf{Q}}_p/\mathbf{Q}_p)$ with distinct Hodge-Tate
weights via the semi-simple modulo $p$ Langlands correspondence. We give some
examples computed with an implementation of this algorithm in SAGE.


title:
Towards monitoring critical microscopic parameters for
  electropermeabilization

abstract:
  Electropermeabilization is a clinical technique in cancer treatment to
locally stimulate the cell metabolism. It is based on electrical fields that
change the properties of the cell membrane. With that, cancer treatment can
reach the cell more easily. Electropermeabilization occurs only with accurate
dosage of the electrical field. For applications, a monitoring for the amount
of electropermeabilization is needed. It is a first step to image the
macroscopic electrical field during the process. Nevertheless, this is not
complete, because electropermeabilization depends on critical individual
properties of the cells such as their curvature. From the macroscopic field,
one cannot directly infer that microscopic state. In this article, we study
effective parameters in a homogenization model as the next step to monitor the
microscopic properties in clinical practice. We start from a physiological cell
model for electropermeabilization and analyze its well-posedness. For a
dynamical homogenization scheme, we prove convergence and then analyze the
effective parameters, which can be found by macroscopic imaging methods. We
demonstrate numerically the sensitivity of these effective parameters to
critical microscopic parameters governing electropermeabilization. This opens
the door to solve the inverse problem of rreconstructing these parameters.


title:
Search for direct pair production of supersymmetric top quarks decaying
  to all-hadronic final states in pp collisions at sqrt(s) = 8 TeV

abstract:
  Results are reported from a search for the pair production of top squarks,
the supersymmetric partners of top quarks, in final states with jets and
missing transverse momentum. The data sample used in this search was collected
by the CMS detector and corresponds to an integrated luminosity of 18.9 inverse
femtobarns of proton-proton collisions at a centre-of-mass energy of 8 TeV
produced by the LHC. The search features novel background suppression and
prediction methods, including a dedicated top quark pair reconstruction
algorithm. The data are found to be in agreement with the predicted
backgrounds. Exclusion limits are set in simplified supersymmetry models with
the top squark decaying to jets and an undetected neutralino, either via a top
quark or through a bottom quark and chargino. Models with the top squark
decaying via a top quark are excluded for top squark masses up to 755 GeV in
the case of neutralino masses below 200 GeV. For decays via a chargino, top
squark masses up to 620 GeV are excluded, depending on the masses of the
chargino and neutralino.


title: Solution of Hypergraph Turan problem

abstract:
  Using original {\it Symmetrical Smoothing Method} we solve $(3,k)$-
hypergraph Turan problem


title:
Identifying spatially asymmetric high-order harmonic emission during the
  falling edge of an intense laser pulse

abstract:
  Two different induced effects of a laser falling edge on high-order harmonic
generation are resolved by solving numerically full-dimensional electronic
time-dependent Schr\"{o}dinger equation beyond the Born-Oppenheimer
approximation. The harmonic spectrum of H$_2^+$ and T$_2^+$ isotopes are
compared to see the effects of a 4-cycle falling edge of a 800 nm, 15-cycle
trapezoidal laser pulse of $I=$3 $\times 10^{14}$ Wcm$^{-2}$ intensity on
harmonic emission spectrum. The harmonic emission at the laser falling part is
negligible for H$_2^+$ due to ionization suppression, but considerable for
T$_2^+$. The falling edge of the laser pulse induces two effects on the HHG in
T$_2^+$. The first well-known effect is non-adiabatic frequency redshift of
generated odd-order harmonics. The second unknown one is spatially asymmetric
harmonic emission which appears as even harmonic orders. In order to clarify
this new effect, spatial distribution of HHG and resolving HHG into different
components are demonstrated. The asymmetric emission would appear for both
atoms and molecules as long as harmonic emission of either rising or falling
edge of an intense trapezoidal or non-trapezoidal laser pulse is dominant.

categories: physics.atom-ph physics.chem-ph physics.comp-ph quant-ph


title:
Models for the evolution of close binaries with He-Star and WD
  components towards Type Ia supernova explosions

abstract:
  Type Ia supernovae (SNe Ia) have been an important tool for astronomy for
quite some time; however, the nature of their progenitors remains somewhat
mysterious. Recent theoretical studies indicated the possibility of producing
thermonuclear detonations of carbon-oxygen white dwarfs (CO WDs) at masses less
than the Chandrasekhar mass through accretion of helium-rich matter, which
would, depending on mass accretion rate, mass, and initial temperature of the
WD, spectrally resemble either a normal SN Ia or a peculiar one. This study
aims to further resolve the state of binary systems comprised of a
sub-Chandrasekhar-mass CO WD and a helium star at the point where an
accretion-induced detonation occurs and constrains the part of the initial
parameter space where this kind of phenomenon is possible. Preexisting data
obtained through simulations of single, constantly accreting CO WDs is used as
an indicator for the behavior of new binary models in which the WD is treated
as a point mass and which include the non-degenerate partner as a fully
resolved stellar model. We parameterize the ignition of the accumulated helium
layer, changes in the WD temperature, and changes in the CO core mass depending
on the mass transfer rate. The initial conditions allowing for detonation do
not form a single contiguous area in the parameter space, whose shape is
profoundly influenced by the behavior of the donor star. Mass loss due to Nova
outbursts acts in favor of detonation. According to our criteria, about 10% of
the detonations in this study can be expected to show spectra consistent with
ordinary SNe Ia; the rest exhibit peculiar features.


title: Quantum critical transport at a continuous metal-insulator transition

abstract:
  In contrast to the first-order correlation-driven Mott metal-insulator
transition (MIT), contin- uous disorder-driven transitions are intrinsically
quantum critical. Here, we investigate transport quantum criticality in the
Falicov-Kimball model, a representative of the latter class in the "strong
disorder" category. Employing cluster-dynamical mean-field theory (CDMFT), we
find clear and anomalous quantum critical scaling behavior manifesting as
perfect mirror symmetry of scaling curves on both sides of the MIT.
Surprisingly, we find that the beta-function, \b{eta}(g), scales like log(g)
deep into the bad-metallic phase as well, providing sound unified basis for
these findings. We argue that such "strong localization" quantum criticality
may manifest in real three-dimensional systems where disorder effects are more
important than electron-electron interactions.


title: Vertex Cover Structural Parameterization Revisited

abstract:
  A pseudoforest is a graph whose connected components have at most one cycle.
Let X be a pseudoforest modulator of graph G, i. e. a vertex subset of G such
that G-X is a pseudoforest. We show that Vertex Cover admits a polynomial
kernel being parameterized by the size of the pseudoforest modulator. In other
words, we provide a polynomial time algorithm that for an input graph G and
integer k, outputs a graph G' and integer k', such that G' has O(|X|12)
vertices and G has a vertex cover of size k if and only if G' has vertex cover
of size k'. We complement our findings by proving that there is no polynomial
kernel for Vertex Cover parameterized by the size of a modulator to a mock
forest (a graph where no cycles share a vertex) unless NP is a subset of
coNP/poly. In particular, this also rules out polynomial kernels when
parameterized by the size of a modulator to outerplanar and cactus graphs.


title:
Spatial plane waves for the nonlinear Schr\"odinger equation: local
  existence and stability results

abstract:
  We consider the Cauchy problem for the nonlinear Schr\"odinger equation on
$\mathbb{R}^2$, $iu_t + u_{xx} + u_{yy} + \lambda|u|^\sigma u =0$, $\lambda\in
\mathbb{R}$, $\sigma>0$. We introduce new functional spaces over which the
initial value problem is well-posed. Their construction is based on
\textit{spatial plane waves} (cf. arXiv:1510.08745). These spaces contain
$H^1(\mathbb{R}^2)$ and do not lie within $L^2(\mathbb{R}^2)$. We prove several
global well-posedness and stability results over these new spaces, including a
new global well-posedness result of $H^1$ solutions with indefinitely large
$H^1$ and $L^2$ norms. Some of these results are proved using a new functional
transform, the \textit{plane wave transform}. We develop a suitable theory for
this transform, prove several properties and solve classical linear PDE's with
it, highlighting its wide range of application.


title:
Filter based Taxonomy Modification for Improving Hierarchical
  Classification

abstract:
  Hierarchical Classification (HC) is a supervised learning problem where
unlabeled instances are classified into a taxonomy of classes. Several methods
that utilize the hierarchical structure have been developed to improve the HC
performance. However, in most cases apriori defined hierarchical structure by
domain experts is inconsistent; as a consequence performance improvement is not
noticeable in comparison to flat classification methods. We propose a scalable
data-driven filter based rewiring approach to modify an expert-defined
hierarchy. Experimental comparisons of top-down HC with our modified hierarchy,
on a wide range of datasets shows classification performance improvement over
the baseline hierarchy (i:e:, defined by expert), clustered hierarchy and
flattening based hierarchy modification approaches. In comparison to existing
rewiring approaches, our developed method (rewHier) is computationally
efficient, enabling it to scale to datasets with large numbers of classes,
instances and features. We also show that our modified hierarchy leads to
improved classification performance for classes with few training samples in
comparison to flat and state-of-the-art HC approaches.


title: Tight LP Approximations for the Optimal Power Flow Problem

abstract:
  DC power flow approximations are ubiquitous in the electricity industry.
However, these linear approximations fail to capture important physical aspects
of power flow, such as the reactive power and voltage magnitude, which are
crucial in many applications to ensure voltage stability and AC solution
feasibility. This paper proposes two LP approximations of the AC optimal power
flow problem, founded on tight polyhedral approximations of the SOC
constraints, in the aim of retaining the good lower bounds of the SOCP
relaxation and relishing the computational efficiency of LP solvers. The high
accuracy of the two LP approximations is corroborated by rigorous computational
evaluations on systems with up to 9241 buses and different operating
conditions. The computational efficiency of the two proposed LP models is shown
to be comparable to, if not better than, that of the SOCP models in most
instances. This performance is ideal for MILP extensions of these LP models
since MILP is computationally more efficient than MIQCP.


title:
Products of Eisenstein series and Fourier expansions of modular forms at
  cusps

abstract:
  We show, for levels of the form $N = p^a q^b N'$ with $N'$ squarefree, that
in weights $k \geq 4$ every cusp form $f \in \mathcal{S}_k(N)$ is a linear
combination of products of certain Eisenstein series of lower weight. In weight
$k=2$ we show that the forms $f$ which can be obtained in this way are
precisely those in the subspace generated by eigenforms $g$ with $L(g, 1) \neq
0$. As an application of such representations of modular forms we can calculate
Fourier expansions of modular forms at arbitrary cusps and we give several
examples of such expansions in the last section.


title: The Ziegler spectrum for derived-discrete algebras

abstract:
  Let $\Lambda$ be a derived-discrete algebra. We show that the Krull-Gabriel
dimension of the homotopy category of projective $\Lambda$-modules, and
therefore the Cantor-Bendixson rank of its Ziegler spectrum, is $2$, thus
extending a result of Bobi\'nski and Krause. We also describe all the
indecomposable pure-injective complexes and hence the Ziegler spectrum for
derived-discrete algebras, extending a result of Z. Han. Using this, we are
able to prove that all indecomposable complexes in the homotopy category of
projective $\Lambda$-modules are pure-injective, so obtaining a class of
algebras for which every indecomposable complex is pure-injective but which are
not derived pure-semisimple.


title:
The Search for Extraterrestrial Intelligence in Earth's Solar Transit
  Zone

abstract:
  Over the past few years, astronomers have detected thousands of planets and
candidate planets by observing their periodic transits in front of their host
stars. Related methods might soon allow studies of the chemical imprints of
life in extrasolar planetary atmospheres. Here, we address the reciprocal
question, namely, from where is Earth detectable by extrasolar observers using
similar methods. We explore Earth's transit zone (ETZ), the projection of a
band around Earth's ecliptic onto the celestial plane, where observers can
detect Earth transits across the Sun. The ETZ is between $0.520^\circ$ and
$0.537^\circ$ wide due to the non-circular Earth orbit. The restricted ETZ
(rETZ), where Earth transits the Sun less than 0.5 solar radii from its center,
is ~$0.262^\circ$ wide. We first compile a target list of 45 K and 37 G dwarf
stars inside the rETZ and within 1 kiloparsec (3260 lightyears) using the
Hipparcos catalog. We then greatly enlarge the number of potential targets by
constructing an analytic galactic disk model and find that ~$10^5$ K and G
dwarf stars should reside within the rETZ. The ongoing GAIA space mission can
potentially discover all G dwarfs among them (several $10^4$) within the next
five years. Many more potentially habitable planets orbit dim, unknown M stars
in the ETZ and other stars that traversed the ETZ long time ago. If any of
these planets host intelligent observers, they could have identified Earth as a
habitable, or even as a living, world, and we could be receiving their
broadcasts today. The K2 mission, the Allen Telescope Array, the upcoming
Square Kilometer Array, or the Green Bank Telescope might detect such
deliberate extraterrestrial messages. Ultimately, the ETZ would be an ideal
region to monitor by the Breakthrough Listen Initiatives, an upcoming survey
that will constitute the most comprehensive search for extraterrestrial
intelligence so far.


title:
Protecting and accelerating adiabatic passage with time-delayed pulse
  sequences

abstract:
  Using numerical simulations of two-photon electronic absorption with
femtosecond pulses in Na$_2$ we show that: i) it is possible to avoid the
characteristic saturation or dumped Rabi oscillations in the yield of
absorption by time-delaying the laser pulses; ii) it is possible to accelerate
the onset of adiabatic passage by using the vibrational coherence starting in a
wave packet; and iii) it is possible to prepare the initial wave packet in
order to achieve full state-selective transitions with broadband pulses. The
findings can be used, for instance, to achieve ultrafast adiabatic passage by
light-induced potentials and understand its intrinsic robustness.


title:
Overcooked agar solutions: impact on the structural and mechanical
  properties of agar gels

abstract:
  Thermoreversible hydrogels are commonly prepared by cooling down to ambient
temperature, aqueous polymer solutions first brought to a boil. The incubation
time of the polymer solution at such a high temperature is traditionally kept
to a minimum to minimize its impact on the subsequent gelation. Here we study
the effect of a prolonged heating of a 1.5\% w/w agar solution at
$T=80^{\circ}$C, well above the gelling temperature. The incubation time
$\mathcal{T}$ of the polysaccharide solution is varied from a few hours up to
five days. We show that the agar solution ages as the result of both the
hydrolysis and the intramolecular oxidation of the polysaccharides. As a
consequence, both the viscosity and the pH of the solution decrease
continuously during the incubation period. Furthermore, samples withdrew at
different incubation times are cooled down to form gels which structure and
mechanical properties are systematically determined. Cryo-microscopy and X-ray
diffraction experiments reveal that agar gels formed from solutions of
increasing incubation times, display a coarser microstructure composed of
micron-sized foils which result from the condensation of the polysaccharides
and contrast with the fibrous-like microstructure of gels prepared from a fresh
agar solution. Along with structural changes, a prolonged incubation time of
the polymer solution at $T=80^{\circ}$C leads to weaker agar gels of
significantly lower shear elastic modulus. Moreover, extensive
macro-indentation experiments coupled to direct visualization show that
increasing the incubation time of the agar solution up to a few days decreases
the yield strain of the gel, while the rupture scenario turns continuously from
brittle to ductile-like. Our study suggests that the incubation time of agar
solutions at high temperature could be used to tune the mechanical properties
of agar-based gels.


title:
Quantum critical magneto-transport at a continuous metal-insulator
  transition

abstract:
  In contrast to the seminal weak localization prediction of a non-critical
Hall constant ($R_{H}$) at the Anderson metal-insulator transition (MIT),
$R_{H}$ in quite a few real disordered systems exhibits both, a strong
$T$-dependence and critical scaling near their MIT. Here, we investigate these
issues in detail within a non-perturbative "strong localization" regime using
cluster-dynamical mean field theory (CDMFT). We uncover $(i)$ clear and
unconventional quantum-critical scaling of the $\gamma$-function, finding that
$\gamma(g_{xy})\simeq$ log$(g_{xy})$ over a wide range spanning the continuous
MIT, very similar to that seen for the longitudinal conductivity, $(ii)$
strongly $T$-dependent and clear quantum critical scaling in both transverse
conductivity and $R_{H}$ at the MIT. We find that these surprising results are
in comprehensive and very good accord with signatures of a novel kind of
localization in disordered NbN near the MIT, providing substantial support for
our "strong" localization view.


title: Moufang sets and structurable division algebras

abstract:
  A Moufang set is essentially a doubly transitive permutation group such that
each point stabilizer contains a normal subgroup which is regular on the
remaining vertices; these regular normal subgroups are called the root groups,
and they are assumed to be conjugate and to generate the whole group.
  It has been known for some time that every Jordan division algebra gives rise
to a Moufang set with abelian root groups. We extend this result by showing
that every structurable division algebra gives rise to a Moufang set, and
conversely, we show that every Moufang set arising from a simple linear
algebraic group of relative rank one over an arbitrary field k of
characteristic different from 2 and 3 arises from a structurable division
algebra.
  We also obtain explicit formulas for the root groups, the \tau-map and the
Hua maps of these Moufang sets. This is particularly useful for the Moufang
sets arising from exceptional linear algebraic groups.


title:
Geometric formulation and multi-dark soliton solution to the defocusinig
  complex short pulse equation

abstract:
  In the present paper, we study the defocusing complex short pulse (CSP)
equations both geometrically and algebraically. From the geometric point of
view, we establish a link of the complex coupled dispersionless (CCD) system
with the motion of space curves in Minkowski space $\mathbf{R}^{2,1}$, then
with the defocusing CSP equation via a hodograph (reciprocal) transformation,
the Lax pair is constructed naturally for the defocusing CSP equation. We also
show that the CCD system of both the focusing and defocusing types can be
derived from the fundamental forms of surfaces such that their curve flows are
formulated. In the second part of the paper, we derive the the defocusing CSP
equation from the single-component extended KP hierarchy by the reduction
method. As a by-product, the $N$-dark soliton solution for the defocusing CSP
equation in the form of determinants for these equations is provided.


title: A Dynamical Solution in Horava-Lifshitz Gravity in the IR limit

abstract:
  Non-stationary null dust in a spherically symmetric spacetime is studied in
the context of a general-covariant Horava-Lifshitz theory. The non-minimal
coupling to matter is considered in the infrared limit. The aim of this paper
is to study whether the collapse of a null dust-like fluid can be a solution of
Ho\v{r}ava-Lifshitz theory in the infrared limit. We have shown that the unique
possible solution is static. This solution represents a Minkowski spacetime
since the energy density is null.


title: A note on the Ostrovsky equation in weighted Sobolev spaces

abstract:
  In this work we consider the initial value problem (IVP) associated to the
Ostrovsky equations $$\left. \begin{array}{rl} u_t+\partial_x^3 u\pm
\partial_x^{-1}u +u \partial_x u &\hspace{-2mm}=0,\qquad\qquad x\in\mathbb R,\;
t\in\mathbb R,\\ u(x,0)&\hspace{-2mm}=u_0(x). \end{array} \right\}$$ We study
the well-posedness of the IVP in the weighted Sobolev spaces
$$Z_{s,\frac{s}2}:=\{u\in H^s(\mathbb R):D_x^{-s} u\in L^2(\mathbb R)\}\cap
L^2(|x|^s dx ),$$ with $\frac34<s\leq 1$.


title: The Arrow of Time in Multivariate Time Series

abstract:
  We prove that a time series satisfying a (linear) multivariate autoregressive
moving average (VARMA) model satisfies the same model assumption in the
reversed time direction, too, if all innovations are normally distributed. This
reversibility breaks down if the innovations are non-Gaussian. This means that
under the assumption of a VARMA process with non-Gaussian noise, the arrow of
time becomes detectable. Our work thereby provides a theoretic justification of
an algorithm that has been used for inferring the direction of video snippets.
We present a slightly modified practical algorithm that estimates the time
direction for a given sample and prove its consistency. We further investigate
how the performance of the algorithm depends on sample size, number of
dimensions of the time series and the order of the process. An application to
real world data from economics shows that considering multivariate processes
instead of univariate processes can be beneficial for estimating the time
direction. Our result extends earlier work on univariate time series. It
relates to the concept of causal inference, where recent methods exploit
non-Gaussianity of the error terms for causal structure learning.


title: Moduli spaces of sheaves on K3 surfaces

abstract:
  In this survey article we describe moduli spaces of simple, stable, and
semistable sheaves on K3 surfaces, following the work of Mukai, O'Grady,
Huybrechts, Yoshioka, and others. We also describe some recent developments,
including applications to the study of Chow rings of K3 surfaces, determination
of the ample and nef cones of irreducible holomorphic symplectic manifolds, and
moduli spaces of Bridgeland stable complexes of sheaves.


title:
Improving Named Entity Recognition for Chinese Social Media with Word
  Segmentation Representation Learning

abstract:
  Named entity recognition, and other information extraction tasks, frequently
use linguistic features such as part of speech tags or chunkings. For languages
where word boundaries are not readily identified in text, word segmentation is
a key first step to generating features for an NER system. While using word
boundary tags as features are helpful, the signals that aid in identifying
these boundaries may provide richer information for an NER system. New
state-of-the-art word segmentation systems use neural models to learn
representations for predicting word boundaries. We show that these same
representations, jointly trained with an NER system, yield significant
improvements in NER for Chinese social media. In our experiments, jointly
training NER and word segmentation with an LSTM-CRF model yields nearly 5%
absolute improvement over previously published results.


title: Computing jumping numbers in higher dimensions

abstract:
  The aim of this paper is to generalize the algorithm to compute jumping
numbers on rational surfaces described in [AAD14] to varieties of dimension at
least 3. Therefore, we introduce the notion of $\pi$-antieffective divisors,
generalizing antinef divisors. Using these divisors, we present a way to find a
small subset of the `classical' candidate jumping numbers of an ideal,
containing all the jumping numbers. Moreover, many of these numbers are
automatically jumping numbers, and in many other cases, it can be easily
checked.


title: Automatic Differentiation Variational Inference

abstract:
  Probabilistic modeling is iterative. A scientist posits a simple model, fits
it to her data, refines it according to her analysis, and repeats. However,
fitting complex models to large data is a bottleneck in this process. Deriving
algorithms for new models can be both mathematically and computationally
challenging, which makes it difficult to efficiently cycle through the steps.
To this end, we develop automatic differentiation variational inference (ADVI).
Using our method, the scientist only provides a probabilistic model and a
dataset, nothing else. ADVI automatically derives an efficient variational
inference algorithm, freeing the scientist to refine and explore many models.
ADVI supports a broad class of models-no conjugacy assumptions are required. We
study ADVI across ten different models and apply it to a dataset with millions
of observations. ADVI is integrated into Stan, a probabilistic programming
system; it is available for immediate use.


title:
Ultrafast, all-optical coherent control of single silicon vacancy colour
  centres in diamond

abstract:
  Recently, the negatively charged silicon vacancy centre (SiV) in diamond has
emerged as a novel promising system for quantum information processing (QIP)
due to its superior spectral properties and advantageous electronic structure:
The SiV offers an optically accessible {\Lambda}-type level structure with a
large orbital level splitting even without the need of an external magnetic
field and previous studies determined the ground state coherence time of the
centre to be on the order of 35-45ns. While these studies already indicate the
feasibility of an ultrafast all-optical coherent control of the SiV, no
experimental realization has been presented so far. Here, we report on optical
Rabi oscillations and Ramsey interference between the ground and the excited
state of the SiV using 12 ps long, resonant rotation pulses. Moreover,
utilizing a {\Lambda}-scheme, we demonstrate Raman-based coherent Rabi
rotations and Ramsey interference within the ground state manifold using a
single, 1ps long off-resonant pulse. These measurements prove the accessibility
of the complete set of single-qubit operations relying solely on optical fields
and pave the way for high-speed QIP applications using SiV centres.


title: Ando dilations and inequalities on noncommutative varieties

abstract:
  We obtain dilation results which simultaneously generalize Sz.-Nagy dilation
theorem for contractions, Ando's dilation theorem for commuting contractions,
Sz.-Nagy--Foias commutant lifting theorem, and Schur's representation for the
unit ball of H^\infty, in the framework of noncommutative varieties in several
variables and Poisson kernels on Fock spaces. This leads to inequalities which,
in the particular case of two contractions, are sharper than Ando's inequality
and Agler-McCarthy's inequality in the setting of commuting contractive
matrices or arbitrary commuting contractions of class C_0. Our results extend
to the bi-ball and a large class of noncommutative varieties.


title: Probing surface states with many-body wave packet scattering

abstract:
  The scattering of 1D matter wave bright solitons on attractive potentials
enables one to populate bound states, a feature impossible with noninteracting
wave packets. Compared to noninteracting states, the populated states are
renormalized by the attractive interactions between atoms and keep the same
topology. This renormalization can even transform a virtual state into a bound
state. By switching off adiabatically the interactions, the trapped wave
packets converge towards the true noninteracting bound states. Our numerical
studies show how such scattering experiments can reveal and characterize the
surface states of a periodic structure whose translational invariance has been
broken. We provide evidence that the corresponding 3D regime should be
accessible with current techniques.


title:
Exact solution of inverse-square-root potential $V\left( r\right)
  =-\frac{\alpha}{\sqrt{r}}$

abstract:
  An exact solution of the three-dimensional spherical symmetry
inverse-square-root potential $V\left( r\right) =-\frac{\alpha}{\sqrt{r}}$,
including scattering and bound-state solutions, is presented.


title:
Hybrid reciprocal lattice: application to layer stress appointment in
  GaAlN/GaN(0001) systems with patterned substrates

abstract:
  Epitaxy of semiconductors is a process of tremendous importance in applied
science and optoelectronic industry. Controlling of defects introduced during
epitaxial growth is a key point in manufacturing devices of high efficiency and
durability. In this work, we demonstrate how useful hybrid reflections are on
the study of epitaxial structures with anisotropic strain gradients due to
patterned substrates. High accuracy to detect and distinguish elastic and
plastic relaxations are one of the greatest advantages of measuring this type
of reflection, as well as the fact that it can be exploited in symmetrical
reflection geometry on a commercial high-resolution diffractometer.


title: Robotic Playing for Hierarchical Complex Skill Learning

abstract:
  In complex manipulation scenarios (e.g. tasks requiring complex interaction
of two hands or in-hand manipulation), generalization is a hard problem.
Current methods still either require a substantial amount of (supervised)
training data and / or strong assumptions on both the environment and the task.
In this paradigm, controllers solving these tasks tend to be complex. We
propose a paradigm of maintaining simpler controllers solving the task in a
small number of specific situations. In order to generalize to novel
situations, the robot transforms the environment from novel situations into a
situation where the solution of the task is already known. Our solution to this
problem is to play with objects and use previously trained skills (basis
skills). These skills can either be used for estimating or for changing the
current state of the environment and are organized in skill hierarchies. The
approach is evaluated in complex pick-and-place scenarios that involve complex
manipulation. We further show that these skills can be learned by autonomous
playing.


title: Lighting the Landscape: Molecular Events Under Dynamic Stark Shifts

abstract:
  A new perspective on how to manipulate molecules by means of very strong
laser pulses is emerging with insights from the so-called light-induced
potentials, which are the adiabatic potential energy surfaces of molecules
severely distorted by the effect of the strong field. Different effects appear
depending on how the laser frequency is tuned, to a certain electronic
transition, creating light-induced avoided crossings, or very off-resonant,
generating Stark shifts. In the former case it is possible to induce dramatic
changes in the geometry and redistribution of charges in the molecule while the
lasers are acting and to fully control photodissociation reactions as well as
other photochemical processes. Several theoretical proposals taken from the
work of the authors are reviewed and analyzed showing the unique features that
the strong-laser chemistry opens to control the transient properties and the
dynamics of molecules.


title: On Morita Equivalences Between KLR Algebras and VV Algebras

abstract:
  This paper is investigative work into the properties of a family of graded
algebras recently defined by Varagnolo and Vasserot, which we call VV algebras.
We compare categories of modules over KLR algebras with categories of modules
over VV algebras, establishing various Morita equivalences. Using these Morita
equivalences we are able to prove several properties of certain classes of VV
algebras such as (graded) affine cellularity and affine quasi-heredity.


title: The SPHERE Challenge: Activity Recognition with Multimodal Sensor Data

abstract:
  This paper outlines the Sensor Platform for HEalthcare in Residential
Environment (SPHERE) project and details the SPHERE challenge that will take
place in conjunction with European Conference on Machine Learning and
Principles and Practice of Knowledge Discovery (ECML-PKDD) between March and
July 2016. The SPHERE challenge is an activity recognition competition where
predictions are made from video, accelerometer and environmental sensors.
Monetary prizes will be awarded to the top three entrants, with Euro 1,000
being awarded to the winner, Euro 600 being awarded to the first runner up, and
Euro 400 being awarded to the second runner up.


title:
Conformal Titanium Nitride in a Porous Silicon Matrix: a Nanomaterial
  for In-Chip Supercapacitors

abstract:
  Today's supercapacitor energy storages are typically discrete devices aimed
for printed boards and power applications. The development of autonomous sensor
networks and wearable electronics and the miniaturisation of mobile devices
would benefit substantially from solutions in which the energy storage is
integrated with the active device. Nanostructures based on porous silicon (PS)
provide a route towards integration due to the very high inherent surface area
to volume ratio and compatibility with microelectronics fabrication processes.
Unfortunately, pristine PS has limited wettability and poor chemical stability
in electrolytes and the high resistance of the PS matrix severely limits the
power efficiency. In this work, we demonstrate that excellent wettability and
electro-chemical properties in aqueous and organic electrolytes can be obtained
by coating the PS matrix with an ultra-thin layer of titanium nitride by atomic
layer deposition. Our approach leads to very high specific capacitance (15
F/cm$^3$), energy density (1.3 mWh/cm$^3$), power density (up to 214 W/cm$^3$)
and excellent stability (more than 13,000 cycles). Furthermore, we show that
the PS-TiN nanomaterial can be integrated inside a silicon chip monolithically
by combining MEMS and nanofabrication techniques. This leads to realisation of
in-chip supercapacitor, i.e., it opens a new way to exploit the otherwise
inactive volume of a silicon chip to store energy.


title: Cotunneling drag effect in Coulomb-coupled quantum dots

abstract:
  In Coulomb drag, a current flowing in one conductor can induce a voltage
across an adjacent conductor via the Coulomb interaction. The mechanisms
yielding drag effects are not always understood, even though drag effects are
sufficiently general to be seen in many low-dimensional systems. In this
Letter, we observe Coulomb drag in a Coulomb-coupled double quantum dot
(CC-DQD) and, through both experimental and theoretical arguments, identify
cotunneling as essential to obtaining a correct qualitative understanding of
the drag behavior.


title:
Specification Test based on Convolution-type Distribution Function
  Estimates for Non-linear Auto-regressive Processes

abstract:
  The paper proposes a specification test based on two estimates of
distribution function. One is the traditional kernel distribution function
estimate and the other is a newly proposed convolution-type distribution
function estimate. Asymptotic properties of the new estimate are studied when
the innovation density is known and when it is unknown. The MISE-type statistic
based on these estimates is suggested to test parametric specifications of the
mean and volatility functions. The relating asymptotic results are obtained and
the finite-sample properties are studied based on the bootstrap methodology. A
simulation study shows that the proposed test competes favorably to benchmark
tests in terms of the empirical level and power.


title:
Approaching hell's kitchen: Molecular daredevil clouds in the vicinity
  of Sgr A*

abstract:
  We report serendipitous detections of line emission with the Atacama Large
Millimeter/submillimeter Array (ALMA) in band 3, 6, and 7 in the central parsec
down to within 1" around Sgr A* at an up to now highest resolution (<0.5") view
of the Galactic Center (GC) in the sub-millimeter (sub-mm) domain. From the 100
GHz continuum and the H39\alpha emission we obtain a uniform electron
temperature around 6000 K for the minispiral. The spectral index of Sgr A* is ~
0.5 at 100 - 250 GHz and ~ 0.0 at 230 - 340 GHz. The bright sources in the
center show spectral indices around -0.1 implying Bremsstrahlung emission,
while dust emission is emerging in the minispiral exterior. Apart from CS,
which is most widespread in the center, H13CO+, HC3N, SiO, SO, C2H, CH3OH, 13CS
and N2H+ are also detected. The bulk of the clumpy emission regions is at
positive velocities and in a region confined by the minispiral northern arm,
bar and the sources IRS 3 and 7. Although partly spatially overlapping with the
radio recombination line (RRL) emission at same negative velocities, the
relation to the minispiral remains unclear. A likely explanation is an
infalling clump consisting of denser cloud cores embedded in diffuse gas. The
central association of clouds (CA) shows three times higher CS/X (X: any other
observed molecule) ratios than the circumnuclear disk (CND) suggesting a
combination of higher excitation, by a temperature gradient and/or IR-pumping,
and abundance enhancement due to UV- and/or X-ray emission. Hence, we conclude
that this CA is closer to the center than the CND is to the center. Moreover,
we find molecular emission at velocities up to 200 km s-1. ...


title:
Flies as Ship Captains? Digital Evolution Unravels Selective Pressures
  to Avoid Collision in Drosophila

abstract:
  Flies that walk in a covered planar arena on straight paths avoid colliding
with each other, but which of the two flies stops is not random.
High-throughput video observations, coupled with dedicated experiments with
controlled robot flies have revealed that flies utilize the type of optic flow
on their retina as a determinant of who should stop, a strategy also used by
ship captains to determine which of two ships on a collision course should
throw engines in reverse. We use digital evolution to test whether this
strategy evolves when collision avoidance is the sole penalty. We find that the
strategy does indeed evolve in a narrow range of cost/benefit ratios, for
experiments in which the "regressive motion" cue is error free. We speculate
that these stringent conditions may not be sufficient to evolve the strategy in
real flies, pointing perhaps to auxiliary costs and benefits not modeled in our
study


title: Uniform Lie Algebras and Uniformly Colored Graphs

abstract:
  Uniform Lie algebras are combinatorially defined two-step nilpotent Lie
algebras which can be used to define Einstein solvmanifolds. These Einstein
spaces often have nontrivial isotropy groups. We derive basic properties of
uniform Lie algebras and we classify uniform Lie algebras with five or fewer
generators. We define a type of directed colored graph called a uniformly
colored graph and establish a correspondence between uniform Lie algebras and
uniformly colored graphs. We present several methods of constructing infinite
families of uniformly colored graphs and corresponding uniform Lie algebras.


title: Quantitative de Jong theorems in any dimension

abstract:
  We develop a new quantitative approach to a multidimensional version of the
well-known {\it de Jong's central limit theorem} under optimal conditions,
stating that a sequence of Hoeffding degenerate $U$-statistics whose fourth
cumulants converge to zero satisfies a CLT, as soon as a Lindeberg-Feller type
condition is verified. Our approach allows one to deduce explicit (and
presumably optimal) Berry-Esseen bounds in the case of general $U$-statistics
of arbitrary order $d\geq1$. One of our main findings is that, for vectors of
$U$-statistics satisfying de Jong' s conditions and whose covariances admit a
limit, componentwise convergence systematically implies joint convergence to
Gaussian: this is the first instance in which such a phenomenon is described
outside the frameworks of homogeneous chaoses and of diffusive Markov
semigroups.


title:
Equilibrium phase behavior of the square-well linear microphase-forming
  model

abstract:
  We have recently developed a simulation approach to calculate the equilibrium
phase diagram of particle-based microphase formers. Here, this approach is used
to calculate the phase behavior of the square-well linear model for different
strengths and ranges of the linear long-range repulsive component. The results
are compared with various theoretical predictions for microphase formation. The
analysis further allows us to better understand the mechanism for microphase
formation in colloidal suspensions.


title: Hybrid Collaborative Filtering with Autoencoders

abstract:
  Collaborative Filtering aims at exploiting the feedback of users to provide
personalised recommendations. Such algorithms look for latent variables in a
large sparse matrix of ratings. They can be enhanced by adding side information
to tackle the well-known cold start problem. While Neu-ral Networks have
tremendous success in image and speech recognition, they have received less
attention in Collaborative Filtering. This is all the more surprising that
Neural Networks are able to discover latent variables in large and
heterogeneous datasets. In this paper, we introduce a Collaborative Filtering
Neural network architecture aka CFN which computes a non-linear Matrix
Factorization from sparse rating inputs and side information. We show
experimentally on the MovieLens and Douban dataset that CFN outper-forms the
state of the art and benefits from side information. We provide an
implementation of the algorithm as a reusable plugin for Torch, a popular
Neural Network framework.


title: Categorified presheaves and sieves

abstract:
  Let $\mathcal C$ be a category of a set of (small) categories. This paper
concerns with the ${\mathbf {Cat}}$-valued presheaves and sieves over category
$\mathcal C.$ Since ${\mathbf {Cat}}$ is not a concrete category, existing
definition of presheaves can not deal with the situation. This paper proposes a
new framework for the purpose. The main result is a version of Yoneda embedding
for ${\mathbf {Cat}}$-valued presheaves, and construction of the ${\mathbf
{Cat}}$-valued sieves over the category ${\mathcal O}(\mathbf B)$ of
subcategories of a given topological category $\mathbf B.$


title:
Horocycle dynamics: new invariants and eigenform loci in the stratum
  H(1,1)

abstract:
  We study dynamics of the horocycle flow on strata of translation surfaces,
introduce new invariants for ergodic measures, and analyze the interaction of
the horocycle flow and real Rel surgeries. We use this analysis to complete and
extend results of Calta and Wortman classifying horocycle-invariant measures in
the eigenform loci. We classify the orbit-closures and prove that every orbit
is equidistributed in its orbit-closure. We also prove equidistribution
statements regarding limits of sequences of measures, some of which have
applications to counting problems.


title: The computation of disconnected bifurcation diagrams

abstract:
  Arclength continuation and branch switching are enormously successful
algorithms for the computation of bifurcation diagrams. Nevertheless, their
combination suffers from three significant disadvantages. The first is that
they attempt to compute only the part of the diagram that is continuously
connected to the initial data; disconnected branches are overlooked. The second
is that the subproblems required (typically determinant calculation and
nullspace construction) are expensive and hard to scale to very large
discretizations. The third is that they can miss connected branches associated
with nonsimple bifurcations, such as when an eigenvalue of even multiplicity
crosses the origin. Without expert knowledge or lucky guesses, these techniques
alone can paint an incomplete picture of the dynamics of a system.
  In this paper we propose a new algorithm for computing bifurcation diagrams,
called deflated continuation, that is capable of overcoming all three of these
disadvantages. The algorithm combines classical continuation with a deflation
technique that elegantly eliminates known branches from consideration, allowing
the discovery of disconnected branches with Newton's method. Deflated
continuation does not rely on any device for detecting bifurcations and does
not involve computing eigendecompositions; all subproblems required in deflated
continuation can be solved efficiently if a good preconditioner is available
for the underlying nonlinear problem. We prove sufficient conditions for the
convergence of Newton's method to multiple solutions from the same initial
guess, providing insight into which unknown branches will be discovered. We
illustrate the success of the method on several examples where standard
techniques fail.


title: Character-based Neural Machine Translation

abstract:
  Neural Machine Translation (MT) has reached state-of-the-art results.
However, one of the main challenges that neural MT still faces is dealing with
very large vocabularies and morphologically rich languages. In this paper, we
propose a neural MT system using character-based embeddings in combination with
convolutional and highway layers to replace the standard lookup-based word
representations. The resulting unlimited-vocabulary and affix-aware source word
embeddings are tested in a state-of-the-art neural MT based on an
attention-based bidirectional recurrent neural network. The proposed MT scheme
provides improved results even when the source language is not morphologically
rich. Improvements up to 3 BLEU points are obtained in the German-English WMT
task.


title: k.p theory of freestanding narrow band gap semiconductor nanowires

abstract:
  We report on a theoretical study of the electronic structures of freestanding
nanowires made from narrow band gap semiconductors GaSb, InSb and InAs. The
nanowires are described by the eight-band k.p Hamiltonians and the band
structures are computed by means of the finite element method in a mixture
basis consisting of linear triangular elements inside the nanowires and
constrained Hermite triangular elements near the boundaries. The nanowires with
two crystallographic orientations, namely the [001] and [111] orientations, and
with different cross-sectional shapes are considered. For each orientation, the
nanowires of the three narrow band gap semiconductors are found to show
qualitatively similar characteristics in the band structures. However, the
nanowires oriented along the two different crystallographic directions are
found to show different characteristics in the valence bands. In particular, it
is found that all the conduction bands show simple, good parabolic dispersions
in both the [001]- and [111]-oriented nanowires, while the top valence bands
show double-maximum structures in the [001]-oriented nanowires, but
single-maximum structures in the [111]-oriented nanowires. The wave functions
and spinor distributions of the band states in these nanowires are also
calculated. It is found that significant mixtures of electron and hole states
appear in the bands of these narrow band gap semiconductor nanowires. The wave
functions exhibit very different distribution patterns in the nanowires
oriented along the [001] direction and the nanowires oriented along the [111]
direction. It is also shown that single-band effective mass theory could not
reproduce all the band state wave functions presented in this work.


title: Grand Challenges in Measuring and Characterizing Scholarly Impact

abstract:
  The constantly growing body of scholarly knowledge of science, technology,
and humanities is an asset of the mankind. While new discoveries expand the
existing knowledge, they may simultaneously render some of it obsolete. It is
crucial for scientists and other stakeholders to keep their knowledge up to
date. Policy makers, decision makers, and the general public also need an
efficient communication of scientific knowledge. Several grand challenges
concerning the creation, adaptation, and diffusion of scholarly knowledge, and
advance quantitative and qualitative approaches to the study of scholarly
knowledge are identified.


title: Some remarks related to Maeda's conjecture

abstract:
  In this article we deal with the problem of counting the number of pairs of
normalized eigenforms $ (f,g) $ of weight $k$ and level $N$ such that $ a_p (f)
= a_p (g) $ where $a_p (f) $ denotes the $p-$th Fourier coefficient of $f$.
Here $p$ is a fixed prime.


title:
Active Requirement Mining of Bounded-Time Temporal Properties of
  Cyber-Physical Systems

abstract:
  This paper uses active learning to solve the problem of mining bounded-time
signal temporal requirements of cyber-physical systems or simply the
requirement mining problem. By utilizing robustness degree, we formulates the
requirement mining problem into two optimization problems, a parameter
synthesis problem and a falsification problem. We then propose a new active
learning algorithm called Gaussian Process Adaptive Confidence Bound (GP-ACB)
to help solving the falsification problem. We show theoretically that the
GP-ACB algorithm has a lower regret bound thus a larger convergence rate than
some existing active learning algorithms, such as GP-UCB. We finally illustrate
and apply our requirement mining algorithm on two case studies, the Ackley's
function and a real world automatic transmission model. The case studies show
that our mining algorithm with GP-ACB outperforms others, such as those based
on Nelder-Mead, by an average of 30% to 40%. Our results demonstrate that there
is a principled and efficient way of extracting requirements for complex
cyber-physical systems.


title: How multiple supernovae overlap to form superbubbles

abstract:
  We explore the formation of superbubbles through energy deposition by
multiple supernovae (SNe) in a uniform medium. We use total energy conserving,
3-D hydrodynamic simulations to study how SNe correlated in space and time
create superbubbles. While isolated SNe fizzle out completely by $\sim 1$ Myr
due to radiative losses, for a realistic cluster size it is likely that
subsequent SNe go off within the hot/dilute bubble and sustain the shock till
the cluster lifetime. For realistic cluster sizes, we find that the bubble
remains overpressured only if, for a given $n_{g0}$, $N_{\rm OB}$ is
sufficiently large. While most of the input energy is still lost radiatively,
superbubbles can retain up to $\sim 5-10\%$ of the input energy in form of
kinetic+thermal energy till 10 Myr for ISM density $n_{g0} \approx 1$
cm$^{-3}$. We find that the mechanical efficiency decreases for higher
densities ($\eta_{\rm mech} \propto n_{g0}^{-2/3}$). We compare the radii and
velocities of simulated supershells with observations and the classical
adiabatic model. Our simulations show that the superbubbles retain only
$\lesssim 10\%$ of the injected energy, thereby explaining the observed smaller
size and slower expansion of supershells. We also confirm that a sufficiently
large ($\gtrsim 10^4$) number of SNe is required to go off in order to create a
steady wind with a stable termination shock within the superbubble. We show
that the mechanical efficiency increases with increasing resolution, and that
explicit diffusion is required to obtain converged results.


title:
A Nonlinear Weighted Total Variation Image Reconstruction Algorithm for
  Electrical Capacitance Tomography

abstract:
  A new iterative image reconstruction algorithm for electrical capacitance
tomography (ECT) is proposed that is based on iterative soft thresholding of a
total variation penalty and adaptive reweighted compressive sensing. This
algorithm encourages sharp changes in the ECT image and overcomes the
disadvantage of the $l_1$ minimization by equipping the total variation with an
adaptive weighting depending on the reconstructed image. Moreover, the
non-linear effect is also partially reduced due to the adoption of an updated
sensitivity matrix. Simulation results show that the proposed algorithm
recovers ECT images more precisely than existing state-of-the-art algorithms
and therefore is suitable for the imaging of multiphase systems in industrial
or medical applications.


title: Cardiac Aging Detection Using Complexity Measures

abstract:
  As we age, our hearts undergo changes which result in reduction in complexity
of physiological interactions between different control mechanisms. This
results in a potential risk of cardiovascular diseases which are the number one
cause of death globally. Since cardiac signals are nonstationary and nonlinear
in nature, complexity measures are better suited to handle such data. In this
study, non-invasive methods for detection of cardiac aging using complexity
measures are explored. Lempel-Ziv (LZ) complexity, Approximate Entropy (ApEn)
and Effort-to-Compress (ETC) measures are used to differentiate between healthy
young and old subjects using heartbeat interval data. We show that both LZ and
ETC complexity measures are able to differentiate between young and old
subjects with only 10 data samples while ApEn requires at least 15 data
samples.


title: On the oldest asteroid families in the main belt

abstract:
  Asteroid families are groups of minor bodies produced by high-velocity
collisions. After the initial dispersions of the parent bodies fragments, their
orbits evolve because of several gravitational and non-gravitational
effects,such as diffusion in mean-motion resonances, Yarkovsky and YORP
effects, close encounters of collisions, etc. The subsequent dynamical
evolution of asteroid family members may cause some of the original fragments
to travel beyond the conventional limits of the asteroid family. Eventually,
the whole family will dynamically disperse and no longer be recognizable.
  A natural question that may arise concerns the timescales for dispersion of
large families. In particular, what is the oldest still recognizable family in
the main belt? Are there any families that may date from the late stages of the
Late Heavy Bombardment and that could provide clues on our understanding of the
primitive Solar System? In this work, we investigate the dynamical stability of
seven of the allegedly oldest families in the asteroid main belt. Our results
show that none of the seven studied families has a nominally mean estimated age
older than 2.7 Gyr, assuming standard values for the parameters describing the
strength of the Yarkovsky force. Most "paleo-families" that formed between 2.7
and 3.8 Gyr would be characterized by a very shallow size-frequency
distribution, and could be recognizable only if located in a dynamically less
active region (such as that of the Koronis family). V-type asteroids in the
central main belt could be compatible with a formation from a paleo-Eunomia
family.


title: Tilted excitation implies odd periodic resonances

abstract:
  Our aim is to unveil how resonances of parametric systems are affected when
symmetry is broken. We showed numerically and experimentally that odd
resonances indeed come about when the pendulum is excited along a tilted
direction. Applying the Melnikov subharmonic function, we not only determined
analytically the loci of saddle-node bifurcations delimiting resonance regions
in parameter space, but also explained these observations by demonstrating
that, under the Melnikov method point of view, odd resonances arise due to an
extra torque that appears in the asymmetric case.


title:
Fundamental stellar parameters for selected T-Tauri stars in the
  Chamaeleon and Rho Ophiuchus star-forming regions

abstract:
  We present the results of an optical photometry and high-resolution
spectroscopy campaign for a modest sample of X-ray selected stars in the
Chamaeleon and Rho Ophiuchus star forming regions. With R~50000 optical
spectra, we establish kinematic membership of the parent association and
confirm stellar youth for each star in our sample. With the acquisition of new
standardized BVIc photometry, in concert with near-infrared data from the
literature, we derive age and mass from stellar positions in model-dependent
Hertzsprung-Russell diagrams. We compare isochronal ages derived using
colour-dependent extinction values finding that, within error bars, ages are
the same irrespective of whether E(B-V), E(V-Ic), E(J-H) or E(H-K) is used to
establish extinction, although model ages tend to be marginally younger for
redder Ecolour values. For Cham I and Eta Cham members we derive ages of ~< 5-6
Myr, whereas our three Eta Cha candidates are more consistent with a ~> 25 Myr
post-T Tauri star population. In Rho Ophiuchus, most stars in our sample have
isochronal ages <10 Myr. Five objects show evidence of strong infrared excess
(Av>5) in the 2MASS colour colour diagram, however in terms of Halpha emission,
all stars except RXJ1625.6-2613 are consistent with being weak-lined T-Tauri
stars. Spectral energy distributions (SEDs) over the range ~ 4000A < wavelength
< 1000 microns, show that only one Chamaeleon star (RXJ1112.7-7637) and three
Rho Ophiuchus stars (ROXR1 13, RXJ1625.6-2613 & RXJ1627.1-2419) reveal
substantial departures from a bare photosphere.


title: Mean radius and shape of Pluto and Charon from New Horizons images

abstract:
  Approach images taken by the LORRI imaging system during the New Horizons
spacecraft encounter have been used to determine the mean radii and shapes of
Pluto and Charon. The primary observations are limb locations derived using
three independent approaches. The resulting mean radii of Pluto and Charon are
1188.3 +/- 1.6 km and 606.0 +/- 1.0 km, respectively (2-sigma). The
corresponding densities are 1854 +/- 11 kg m-3 and 1701 +/- 33 kg m-3
(2-sigma). The Charon radius value is consistent with previous Earth-based
occultation estimates. The Pluto radius estimate is consistent with solar
occultation measurements performed by the ALICE and Fine Sun Sensor instruments
on New Horizons. Neither Pluto nor Charon show any evidence for
tidal/rotational distortions; upper bounds on the oblateness are <0.6% and
<0.5%, respectively.


title: Hilbertian Toposes Epsilon Toposes

abstract:
  We study Hilbert's epsilon calculus and Hilbert's partial epsilon calculus in
toposes.


title:
Constraining the supermassive black holes evolution through the
  continuity equation

abstract:
  The population of supermassive black holes (SMBHs) is composed by quiescent
SMBHs, such as those seen in local galaxies including the Milky Way's, and
active ones, resulting in quasars and active galactic nuclei (AGN). Outside our
neighbourhood, all the information we have on SMBHs is derived from quasars and
AGN, giving us a partial view. We study the evolution of the SMBH population,
total and active, by the continuity equation, backwards in time from z=0 to
z=4. Type-1 and type-2 AGN are differentiated in the model on the basis of the
Eddington ratio distribution, chosen on the basis of observational estimates.
The duty cycle is obtained by matching the luminosity function of quasars, and
the average radiative efficiency is the only free parameter in the model. For
higher radiative efficiencies (>~0.07) a large fraction of the SMBH population,
most of them quiescent, must already be in place by z=4. For lower radiative
efficiencies (~0.05), the duty cycle increases with the redshift and the SMBH
population evolves dramatically since z=4. The mass function of active SMBHs
does not depend on the choice of the radiative efficiency or of the local SMBH
mass function, but it is mainly determined by the quasar luminosity function,
once the Eddington ratio distribution is fixed. Only a direct measurement of
the total BHMF at redshifts z>~2 could break these degeneracies giving
important constraints on the average radiative efficiency. Focusing on type-1
AGN, for which observational estimates of the mass function and Eddington ratio
distribution exist at various redshift, models with lower radiative
efficiencies reproduce better the high-mass end of the mass function at high-z,
but they tend to over-predict it at low-z, and vice-versa for models with
higher radiative efficiencies.


title:
Low frequency radio observations of SN 2011dh and the evolution of its
  post-shock plasma properties

abstract:
  We present late time, low frequency observations of SN 2011dh made using the
Giant Metrewave Radio Telescope (GMRT). Our observations at $325\ \rm MHz$,
$610\ \rm MHz$ and $1280\ \rm MHz$ conducted between $93-421\ \rm days$ after
the explosion supplement the millimeter and centimeter wave observations
conducted between $4-15 \ \rm days$ after explosion using the Combined Array
for Research in Millimeter-wave Astronomy (CARMA) and extensive radio
observations ($ 1.0-36.5\ \rm GHz$) conducted between $16-93\ \rm days$ after
explosion using Jansky Very Large Array (JVLA). We fit a synchrotron self
absorption model (SSA) to the $610\ \rm MHz$ and $1280\ \rm MHz$ radio light
curves. We use it to determine the radius ($R_{\rm p}$) and magnetic field
($B_{\rm p}$) at $173$ \& $323$ days after the explosion. A comparison of the
peak radio luminosity $L_{\rm op}$, with the product of the peak frequency
$\nu_{\rm p}$ and time to peak $t_{\rm p}$ shows that the supernova evolves
between the epochs of CARMA, JVLA and GMRT observations. It shows a general
slowing down of the expansion speed of the radio emitting region on a timescale
of several hundred days during which the shock is propagating through a
circumstellar medium set up by a wind with a constant mass loss parameter,
$\dot M/v_{\rm w}$. We derive the mass loss parameter ($A_{\star}$) based on
$610\ \rm MHz$ and $1280\ \rm MHz$ radio light curves, which are found to be
consistent with each other within error limits.


title: Comment on "On the uncomputability of the spectral gap"

abstract:
  The aim of this short note is to clarify some of the claims made in the
comparison made in [S. Lloyd, On the uncomputability of the spectral gap,
arXiv:1602.05924] between our recent result [T.S. Cubitt, D. Perez-Garcia, M.M.
Wolf, Undecidability of the spectral gap, Nature 528, 207-211 (2015),
arXiv:1502.04573] and his 1994 paper [S. Lloyd, Necessary and sufficient
conditions for quantum computation, J. Mod. Opt. 41(12), 2503-2520 (1994)].


title: Radiation from an emitter in the ghost free scalar theory

abstract:
  We study radiation emitted by a time-dependent source of a scalar massless
field in the framework of the ghost-free modifications of the theory. We
consider a simple model of the emitter: namely,we assume that it is point-like
and monochromatic. We focused on the most common versions of the ghost-free
theory, where the propagator $\Box^{-1}$ is modified as follows
$\exp(-(\Box/\mu^2)^N) \Box^{-1}$, where $\mu$ is the characteristic mass-scale
of such $GF_N$-theory. We demonstrated that far from the source, in the
wave-zone, the radiation asymptotically converges to its "classical" value for
any $N\ge 1$. However, in the near-zone the behavior of the field is quite
different from the "classical" case. The difference of field amplitude for the
ghost-free field and for the classical one has an oscillatory behavior in this
domain. A number of oscillations increases with $N$. The amplitude of these
oscillations remain finite for even $N$, while it infinitely grows with
frequency for odd $N$. This behavior indicates that even in the classical
domain $GF_N$ theories might have pathological behavior.


title:
Direct determinations of the nucleon and pion $\sigma$ terms at nearly
  physical quark masses

abstract:
  We present a high statistics study of the pion and nucleon light and strange
quark sigma terms using $N_f=2$ dynamical non-perturbatively improved clover
fermions with a range of pion masses down to $m_\pi\sim 150$ MeV and several
volumes, $Lm_\pi=3.4$ up to $6.7$, and lattice spacings, $a=0.06-0.08$ fm,
enabling a study of finite volume and discretisation effects for $m_\pi\gtrsim
260$ MeV. Systematics are found to be reasonably under control. For the nucleon
we obtain $\sigma_{\pi N}=35(6)$ MeV and $\sigma_s=35(12)$ MeV, or equivalently
in terms of the quark fractions, $f_{T_u}=0.021(4)$, $f_{T_d}=0.016(4)$ and
$f_{T_s}=0.037(13)$, where the errors include estimates of both the systematic
and statistical uncertainties. These values, together with perturbative
matching in the heavy quark limit, lead to $f_{T_c}=0.075(4)$,
$f_{T_b}=0.072(2)$ and $f_{T_t}=0.070(1)$. In addition, through the use of the
(inverse) Feynman-Hellmann theorem our results for $\sigma_{\pi N}$ are shown
to be consistent with the nucleon masses determined in the analysis. For the
pion we implement a method which greatly reduces excited state contamination to
the scalar matrix elements from states travelling across the temporal boundary.
This enables us to demonstrate the Gell-Mann-Oakes-Renner expectation
$\sigma_\pi=m_\pi/2$ over our range of pion masses.


title:
Non-equilibrium fluctuations and metastability arising from non-additive
  interactions in dissipative multi-component Rydberg gases

abstract:
  We study the out-of-equilibrium dynamics of dissipative gases of atoms
excited to two or more high-lying Rydberg states. This situation bears
interesting similarities to classical binary (in general $p$-ary) mixtures of
particles. The effective forces between the components are determined by the
inter-level and intra-level interactions of Rydberg atoms. These systems permit
to explore new parameter regimes which are physically inaccessible in a
classical setting, for example one in which the mixtures exhibit non-additive
interactions. In this situation the out-of-equilibrium evolution is
characterized by the formation of metastable domains that reach partial
equilibration long before the attainment of stationarity. In experimental
settings with mesoscopic sizes, this collective behavior may in fact take the
appearance of dynamic symmetry breaking.


title: Reduced Description of Stellar Dynamics by Moments of Gravitation Field

abstract:
  Because of absence of time derivatives from scalar potential as a generalized
coordinate of gravitation field (GF) in action of nonrelativistic gravitating
system, application of the Hamilton method for description of GF mechanics was
impossible. In the paper a transformation of the generalized coordinate of GF,
that is based on continuity equation and minimal action principle, is proposed.
A potential vector is introduced that is similar to fixing of Hamilton gauge of
the electromagnetic field. This transformation gives possibility of the
calculation a Hamilton function, removes mathematical troubles of the Jeans
theory (Jeans swindle) and allows to construct kinetic theory of GF using
statistical mechanics methods.


title: Loewner evolution of hedgehogs and 2-conformal measures of circle maps

abstract:
  Let $f$ be a germ of holomorphic diffeomorphism with an irrationally
indifferent fixed point at the origin in $\mathbb{C}$ (i.e. $f(0) = 0, f'(0) =
e^{2\pi i \alpha}, \alpha \in \mathbb{R} - \mathbb{Q}$). Perez-Marco showed the
existence of a unique continuous monotone one-parameter family of nontrivial
invariant full continua containing the fixed point called Siegel compacta, and
gave a correspondence between germs and families $(g_t)$ of circle maps
obtained by conformally mapping the complement of these compacts to the
complement of the unit disk. The family of circle maps $(g_t)$ is the orbit of
a locally-defined semigroup $(\Phi_t)$ on the space of analytic circle maps
which we show has a well-defined infinitesimal generator $X$. The explicit form
of $X$ is obtained by using the Loewner equation associated to the family of
hulls $(K_t)$. We show that the Loewner measures $(\mu_t)$ driving the equation
are 2-conformal measures on the circle for the circle maps $(z \mapsto
\overline{g_t(\overline{z})})$.


title: MOT16: A Benchmark for Multi-Object Tracking

abstract:
  Standardized benchmarks are crucial for the majority of computer vision
applications. Although leaderboards and ranking tables should not be
over-claimed, benchmarks often provide the most objective measure of
performance and are therefore important guides for reseach.
  Recently, a new benchmark for Multiple Object Tracking, MOTChallenge, was
launched with the goal of collecting existing and new data and creating a
framework for the standardized evaluation of multiple object tracking methods.
The first release of the benchmark focuses on multiple people tracking, since
pedestrians are by far the most studied object in the tracking community. This
paper accompanies a new release of the MOTChallenge benchmark. Unlike the
initial release, all videos of MOT16 have been carefully annotated following a
consistent protocol. Moreover, it not only offers a significant increase in the
number of labeled boxes, but also provides multiple object classes beside
pedestrians and the level of visibility for every single object of interest.


title:
Robust Defense Strategy for Gas-Electric Systems Against Malicious
  Attacks

abstract:
  This paper proposes a methodology to identify and protect vulnerable
components of connected gas and electric infrastructures from malicious
attacks, and to guarantee a resilient operation by deploying valid corrective
actions (while accounting for the interdependency of gas pipeline network and
power transmission network). The proposed mathematical formulation reduces to a
tri-level optimization problem, where the lower level is a multiperiod economic
dispatch of the gas-electric system, the middle level distinguishes the most
threatening attack on the coupled physical infrastructures, and the upper level
provides optimal preventive decisions to reinforce the vulnerable components
and increase the system resilience. By reformulating the lower level problem as
a mixed integer linear programming (MILP), a nested column-and-constraint
generation (C\&CG) algorithm is developed to solve the min-max-min model. Case
studies on two test systems demonstrate the effectiveness and efficiency of the
proposed methodology.


title:
Thermo-magnetic properties of the strong coupling in the local
  Nambu--Jona-Lasinio model

abstract:
  We study the thermo-magnetic properties of the strong coupling constant G and
quark mass M entering the Nambu-Jona-Lasinio model. For this purpose, we
compute the quark condensate and compare it to lattice QCD (LQCD) results to
extract the behavior of G and M as functions of the magnetic field strength and
temperature. We find that at zero temperature, where the LQCD condensate is
found to monotonically increase with the field strength, M also increases
whereas G remains approximately constant. However, for temperatures above the
chiral/deconfinement phase transitions, where the LQCD condensate is found to
monotonically decrease with increasing field, M and G also decrease
monotonically. For finite temperatures, below the transition temperature, we
find that both G and M initially grow and then decrease with increasing field
strength. To study possible consequences of the extracted temperature and
magnetic field dependence of G and M, we compute the pressure and compare to
LQCD results, finding an excellent qualitative agreement. In particular, we
show that the transverse pressure, as a function of the field strength, is
always negative for temperatures below the transition temperature whereas it
starts off being positive and then becomes negative for temperatures above the
transition temperature, also in agreement with LQCD results. We also show that
for the longitudinal pressure to agree with LQCD calculations, the system
should be described as a diamagnet. We argue that the turnover of M and G as
functions of temperature and field strength is a key element that drives the
behavior of the quark condensate going across the transition temperature and
provides clues for a better understanding of the inverse magnetic catalysis
phenomenon.


title:
Spin Manipulation in Graphene by Chemically-Induced Sublattice
  Pseudospin Polarization

abstract:
  Spin manipulation is one of the most critical challenges to realize
spin-based logic devices and spintronic circuits. Graphene has been heralded as
an ideal material to achieve spin manipulation but so far new paradigms and
demonstrators are limited. Here we show that certain impurities such as
fluorine ad-atoms, which locally break sublattice symmetry without the
formation of strong magnetic moment, could result in a remarkable variability
of spin transport characteristics. The impurity resonance level is found to be
associated with a long range sublattice pseudospin polarization, which by
locally decoupling spin and pseudospin dynamics, provokes a huge spin lifetime
electron-hole asymmetry. In the dilute impurity limit, spin lifetimes could be
tuned electrostatically from hundred picoseconds to several nanoseconds,
providing a protocol to chemically engineer an unprecedented spin device
functionality.


title: Twist-bend coupling and the torsional response of double-stranded DNA

abstract:
  Recent magnetic tweezers experiments have reported systematic deviations of
the twist response of double-stranded DNA from the predictions of the twistable
worm-like chain model. Here we show, by means of analytical results and
computer simulations, that these discrepancies can be resolved if a coupling
between twist and bend is introduced. We obtain an estimate of 40 $\pm$ 10 nm
for the twist-bend coupling constant. Our simulations are in good agreement
with high-resolution, magnetic-tweezers torque data. Although the existence of
twist-bend coupling was predicted long ago (Marko and Siggia, Macromolecules
27, 981 (1994)), its effects on the mechanical properties of DNA have been so
far largely unexplored. We expect that this coupling plays an important role in
several aspects of DNA statics and dynamics.


title: GONG ClassicMerge: Pipeline and Product

abstract:
  A recent processing effort has been undertaken in order to extend the
range-of-coverage of the GONG merged dopplergrams. The GONG-Classic-era
observations have now been merged to provide, albeit at lower resolution, mrvzi
data as far back as May of 1995. The contents of this document provide an
overview of what these data look like, the processing steps used to generate
them from the original site observations, and the outcomes of a few initial
quality-assurance tests designed to validate the final merged images. Based on
these tests, the GONG project is releasing this data product to the user
community (http://nisp.nso.edu/data).


title: Effect of the vibration profile on shallow granular systems

abstract:
  We describe the collective behavior of a system of many inelastic spherical
particles inside a box which is being periodically vibrated. The box is
shallow, with large horizontal dimensions, while the height is less than two
particle diameters. The vibrations are not symmetric: the time the box is
moving up is, in general, different to the time it is moving down. The limit
cycles of isolated grains are largely affected by the asymmetry of the
vibration mode, increasing the size in phase space of the chaotic regions. When
many grains are placed in the box, the phase separation between dense,
solid-like regions, coexisting with fluid-like regions takes place at smaller
global densities for asymmetric vibration profiles. Besides, the order
parameter of the transition takes larger values when asymmetric forcing is
used.


title: Some Remarks on Conway and Iteration Theories

abstract:
  We present an axiomatization of Conway theories which yields,as a corollary,
a very concise axiomatization of iteration theories satisfying the functorial
implication for base morphisms.