title:
Long-term Optical Studies of the Be/X-ray Binary RX J0440.9+4431/LS V+44
  17

abstract:
  We present the spectroscopic and photometric observations on the Be/X-ray
binary RX~J0440.9+4431 from 2001 to 2014. The short-term and long-term
variability of the H$\alpha$ line profile indicates that one-armed global
oscillations existed in the circumstellar disk. Several positive and negative
correlations between the $V$-band brightness and the H$\alpha$ intensity
\textbf{were} found from the long-term photometric and spectroscopic
observations. We suggest that the monotonic increase of the $V$-band brightness
and the H$\alpha$ brightness between our 2005-2007 observations might be the
result of a continuous mass ejection from the central Be star, while the
negative correlation in 2007-2010 should be caused by the cessation of mass
loss from the Be star just before the decline in $V$-band brightness began
(around our 2007 observations). With the extension of the ejection material,
the largest circumstellar disk during the last two decades has been observed in
our 2010 observations with an equivalent width of $\sim$$-12.88$ \AA, which
corresponds to a circumstellar disk with a size of 12.9 times the radius of the
central Be star. Three consecutive X-ray outbursts peaking around MJD 55293,
55444, and 55591 might be connected with the largest circumstellar disk around
the Be star. We also use the orbital motion of the neutron star as a probe to
constrain the structure of the circumstellar disk and estimate the eccentricity
of the binary system to be $\ge$ 0.4. After three years of the H$\alpha$
intensity decline after the X-ray outbursts, a new circumstellar disk was being
formed around the Be star after our 2013 observations.


title: The Ricci curvature on directed graphs

abstract:
  In this paper, we consider the Ricci curvature of a directed graph, based on
Lin-Lu-Yau's definition. We give some properties of the Ricci curvature,
including conditions for a directed regular graph to be Ricci-flat. Moreover,
we calculate the Ricci curvature of the cartesian product of directed graphs.


title: Dimensional reduction for the general Markov model on phylogenetic trees

abstract:
  We present a method of dimensional reduction for the general Markov model of
sequence evolution on a phylogenetic tree. We show that taking certain linear
combinations of the associated random variables (site pattern counts) reduces
the dimensionality of the model from exponential in the number of extant taxa,
to quadratic in the number of taxa, while retaining the ability to
statistically identify phylogenetic divergence events. A key feature is the
identification of an invariant subspace which depends only bilinearly on the
model parameters, in contrast to the usual multi-linear dependence in the full
space. We discuss potential applications including the computation of split
(edge) weights on phylogenetic trees from observed sequence data.


title:
A Markov chain model for the search time for max degree nodes in a graph
  using a biased random walk

abstract:
  We consider the problem of estimating the expected time to find a maximum
degree node on a graph using a (parameterized) biased random walk. For
assortative graphs the positive degree correlation serves as a local gradient
for which a bias towards selecting higher degree neighbors will on average
reduce the search time. Unfortunately, although the expected absorption time on
the graph can be written down using the theory of absorbing Markov chains,
computing this time is infeasible for large graphs. With this motivation, we
construct an absorbing Markov chain with a state for each degree of the graph,
and observe computing the expected absorption time is now computationally
feasible. Our paper finds preliminary results along the following lines: i)
there are graphs for which the proposed Markov model does and graphs for which
the model does not capture the absorbtion time, ii) there are graphs where
random sampling outperforms biased random walks, and graphs where biased random
walks are superior, and iii) the optimal bias parameter for the random walk is
graph dependent, and we study the dependence on the graph assortativity.


title:
Spatial interferences in the electron transport of heavy fermion
  materials

abstract:
  The scanning tunneling microscopy/spectroscopy and the point contact
spectroscopy represent one of the major progresses in recent heavy fermion
research. Both have revealed important information on the composite nature of
the emergent heavy electron quasiparticles. However, a detailed and thorough
microscopic understanding of the similarities and differences in the underlying
physical processes of these techniques is still lacking. Here we study the
electron transport in the normal state of the periodic Anderson lattice by
using the Keldysh nonequilibrium Green's function technique. In addition to the
well-known Fano interference between the conduction and f-electron channels,
our results further reveal the effect of spatial interference between different
spatial paths at the interface on the differential conductance and their
interesting interplay with the band features such as the hybridization gap and
the Van Hove singularity. We find that the spatial interference leads to a
weighted average in the momentum space for the electron transport and could
cause suppression of the electronic band features under certain circumstances.
In particular, it reduces the capability of probing the f-electron spectral
weight near the edges of the hybridization gap for large interface depending on
the Fermi surface of the lead. Our results indicates an intrinsic inefficiency
of the point contact spectroscopy in probing the f-electrons.


title: Top-N Recommendation with Novel Rank Approximation

abstract:
  The importance of accurate recommender systems has been widely recognized by
academia and industry. However, the recommendation quality is still rather low.
Recently, a linear sparse and low-rank representation of the user-item matrix
has been applied to produce Top-N recommendations. This approach uses the
nuclear norm as a convex relaxation for the rank function and has achieved
better recommendation accuracy than the state-of-the-art methods. In the past
several years, solving rank minimization problems by leveraging nonconvex
relaxations has received increasing attention. Some empirical results
demonstrate that it can provide a better approximation to original problems
than convex relaxation. In this paper, we propose a novel rank approximation to
enhance the performance of Top-N recommendation systems, where the
approximation error is controllable. Experimental results on real data show
that the proposed rank approximation improves the Top-$N$ recommendation
accuracy substantially.


title:
MPInterfaces: A Materials Project based Python Tool for High-Throughput
  Computational Screening of Interfacial Systems

abstract:
  A Materials Project based open-source Python tool, MPInterfaces, has been
developed to automate the high-throughput computational screening and study of
interfacial systems. The framework encompasses creation and manipulation of
interface structures for solid/solid hetero-structures, solid/implicit solvents
systems, nanoparticle/ligands systems; and the creation of simple
system-agnostic workflows for in depth computational analysis using
density-functional theory or empirical energy models. The package leverages
existing open-source high-throughput tools and extends their capabilities
towards the understanding of interfacial systems. We describe the various
algorithms and methods implemented in the package. Using several test cases, we
demonstrate how the package enables high-throughput computational screening of
advanced materials, directly contributing to the Materials Genome Initiative
(MGI), which aims to accelerate the discovery, development, and deployment of
new materials.


title:
The bandmerged Planck Early Release Compact Source Catalogue: Probing
  sub-structure in the molecular gas at high Galactic latitude

abstract:
  The Planck Early Release Compact Source Catalogue (ERCSC) includes nine lists
of highly reliable sources, individually extracted at each of the nine Planck
frequency channels. To facilitate the study of the Planck sources, especially
their spectral behaviour across the radio/infrared frequencies, we provide a
"bandmerged" catalogue of the ERCSC sources. This catalogue consists of 15191
entries, with 79 sources detected in all nine frequency channels of Planck and
6818 sources detected in only one channel. We describe the bandmerging
algorithm, including the various steps used to disentangle sources in confused
regions. The multi-frequency matching allows us to develop spectral energy
distributions of sources between 30 and 857 GHz, in particular across the 100
GHz band, where the energetically important CO J=1->0 line enters the Planck
bandpass. We find ~3-5sigma evidence for contribution to the 100 GHz intensity
from foreground CO along the line of sight to 147 sources with |b|>30 deg. The
median excess contribution is 4.5+/-0.9 percent of their measured 100 GHz flux
density which cannot be explained by calibration or beam uncertainties. This
translates to 0.5+/-0.1 K km s^{-1} of CO which must be clumped on the scale of
the Planck 100 GHz beam, i.e., ~10 arcmin. If this is due to a population of
low mass (~15 Msun) molecular gas clumps, the total mass in these clumps may be
more than 2000 Msun. Further, high-spatial-resolution, ground-based
observations of the high-latitude sky will help shed light on the origin of
this diffuse, clumpy CO emission.


title: An electro-optic waveform interconnect based on quantum interference

abstract:
  The ability to modulate an optical field via an electric field is regarded as
a key function of electro-optic interconnects, which are used in optical
communications and information processing systems. One of the main required
devices for such interconnects is the electro-optic modulator (EOM). Current
EOM based on the electro-optic effect and the electro-absorption effect often
is bulky and power inefficient due to the weak electro-optic properties of its
constituent materials. Here we propose a new mechanism to produce an
arbitrary-waveform EOM based on the quantum interference, in which both the
real and imaginary parts of the susceptibility are engineered coherently with
the superhigh efficiency. Based on this EOM, a waveform interconnect from the
voltage to the modulated optical absorption is realised. We expect that such a
new type of electro-optic interconnect will have a broad range of applications
including the optical communications and network.


title: Identifying and characterizing Sybils in the Tor network

abstract:
  Being a volunteer-run, distributed anonymity network, Tor is vulnerable to
Sybil attacks. Little is known about real-world Sybils in the Tor network, and
we lack practical tools and methods to expose Sybil attacks. In this work, we
develop sybilhunter, the first system for detecting Sybil relays based on their
appearance, such as configuration; and behavior, such as uptime sequences. We
used sybilhunter's diverse analysis techniques to analyze nine years of
archived Tor network data, providing us with new insights into the operation of
real-world attackers. Our findings include diverse Sybils, ranging from
botnets, to academic research, and relays that hijack Bitcoin transactions. Our
work shows that existing Sybil defenses do not apply to Tor, it delivers
insights into real-world attacks, and provides practical tools to uncover and
characterize Sybils, making the network safer for its users.


title:
Picometer-resolution dual-comb spectroscopy with a free-running fibre
  laser

abstract:
  Dual-comb spectroscopy utilizes two sets of comb lines with slightly
different comb-tooth-spacings, and optical spectral information is acquired by
measuring the radio-frequency beat notes between the sets of comb lines. It
holds the promise as a real-time, high-resolution analytical spectroscopy tool
for a range of applications. However, the stringent requirement on the
coherence between comb lines from two separate lasers and the sophisticated
control system to achieve that have confined the technology to the top
metrology laboratories. By replacing control electronics with an all-optical
dual-comb lasing scheme, a simplified dual-comb spectroscopy scheme is
demonstrated using just one dual-wavelength, passively mode-locked fiber laser.
Dual-comb pulses with a repetition-frequency difference determined by the
intracavity dispersion are shown to be sufficiently stable against common-mode
cavity drifts and noises. As sufficiently low relative linewidth is maintained
between two sets of comb lines, capability to resolve RF beat notes between
comb teeth and picometer-wide optical spectral features is demonstrated using a
simple data acquisition and processing system in an all-fiber setup.
Possibility to use energy-efficient, free-running fiber lasers with a small
comb-tooth-spacing could enable the realization of low-cost dual-comb
spectroscopy systems affordable to more applications.


title:
Time-resolved Measurement of Quadrupole Wakefields in Corrugated
  Structures

abstract:
  Corrugated structures have recently been widely used for manipulating
electron beam longitudinal phase space and for producing THz radiation. Here we
report on time-resolved measurements of the quadrupole wakefields in planar
corrugated structures. It is shown that while the time- dependent quadrupole
wakefield produced by a planar corrugated structure causes significant growth
in beam transverse emittance, it can be effectively canceled with a second
corrugated structure with orthogonal orientation. The strengths of the
time-dependent quadrupole wakefields for various corrugated structure gaps are
also measured and found to be in good agreement with theories. Our work should
forward the applications of corrugated structures in many accelerator based
scientific facilities.


title: Generalized Polynomial modules over the Virasoro algebra

abstract:
  Let $\mathcal{B}_r$ be the $(r+1)$-dimensional quotient Lie algebra of the
positive part of the Virasoro algebra $\mathcal{V}$. Irreducible
$\mathcal{B}_r$-modules were used to construct irreducible Whittaker modules in
[MZ2] and irreducible weight modules with infinite dimensional weight spaces
over $\mathcal{V}$ in [LLZ].In the present paper, we construct non-weight
Virasoro modules
  $F(M, \Omega(\lambda,\beta))$ from irreducible $\mathcal{B}_r$-modules $M$
and $(\mathcal{A},\mathcal{V})$-modules $\Omega(\lambda,\beta)$.
  We give necessary and sufficient conditions for the Virasoro module $F(M,
\Omega(\lambda,\beta))$ to be irreducible. Using the weighting functor
introduced by J. Nilsson, we also we also give the isomorphism criterion for
two $F(M, \Omega(\lambda,\beta))$.


title:
Stimulated Raman Adiabatic Passage for Improved Performance of a Cold
  Atom Electron and Ion Source

abstract:
  We implement high-efficiency coherent excitation to a Rydberg state using
stimulated Raman adiabatic passage in a cold atom electron and ion source. We
achieve an efficiency of 60% averaged over the laser excitation volume with a
peak efficiency of 82%, a 1.6 times improvement relative to incoherent
pulsed-laser excitation. Using pulsed electric field ionization of the Rydberg
atoms we create electron bunches with durations of 250 ps. High-efficiency
excitation will increase source brightness, crucial for ultrafast electron
diffraction experiments, and coherent excitation to high-lying Rydberg states
could allow for the reduction of internal bunch heating and the creation of a
high-speed single ion source.


title: Chain Reconnections observed in Sympathetic Eruptions

abstract:
  The nature of various plausible causal links between sympathetic events is
still a controversial issue. In this work, we present multi-wavelength
observations of sympathetic eruptions, associated flares and coronal mass
ejections (CMEs) occurring on 2013 November 17 in two close-by active regions.
Two filaments i.e., F1 and F2 are observed in between the active regions.
Successive magnetic reconnections, caused by different reasons (flux
cancellation, shear and expansion) have been identified during the whole event.
The first reconnection occurred during the first eruption via flux cancellation
between the sheared arcades overlying filament F2, creating a flux rope and
leading to the first double ribbon solar flare. During this phase we observed
the eruption of overlaying arcades and coronal loops, which leads to the first
CME. The second reconnection is believed to occur between the expanding flux
rope of F2 and the overlying arcades of the filament F1. We suggest that this
reconnection destabilized the equilibrium of filament F1, which further
facilitated its eruption. The third stage of reconnection occurred in the wake
of the erupting filament F1 between the legs of overlying arcades. This may
create a flux rope and the second double ribbon flare and a second CME. The
fourth reconnection was between the expanding arcades of the erupting filament
F1 and the nearby ambient field, which produced the bi-directional plasma flows
towards both upward and downward. Observations and a nonlinear force-free field
extrapolation confirm the possibility of reconnection and the causal link
between the magnetic systems.


title: The Total Green's Function of a Non-Interacting System

abstract:
  Despite its centrality in the mathematical structure of perturbative
many-body theory, the total Green's function for the many-body time-dependent
Schrodinger equation has been ignored for decades, superseded by
single-particle Green's functions, for which a vast portion of the literature
has been devoted. In this paper, we give the first computation the total
Green's function for the time-dependent Schrodinger equation for a
non-interacting system of identical particles, setting the stage for a fresh
interpretation of perturbative many-body physics.


title:
Some non-existence and asymptotic existence results for weighing
  matrices

abstract:
  Orthogonal designs and weighing matrices have many applications in areas such
as coding theory, cryptography, wireless networking and communication. In this
paper, we first show that if positive integer $k$ cannot be written as the sum
of three integer squares, then there does not exist any skew-symmetric weighing
matrix of order $4n$ and weight $k$, where $n$ is an odd positive integer. Then
we show that for any square $k$, there is an integer $N(k)$ such that for each
$n\ge N(k)$, there is a symmetric weighing matrix of order $n$ and weight $k$.
Moreover, we improve some of the asymptotic existence results for weighing
matrices obtained by Eades, Geramita and Seberry.


title:
Expectation Consistent Approximate Inference: Generalizations and
  Convergence

abstract:
  Approximations of loopy belief propagation, including expectation propagation
and approximate message passing, have attracted considerable attention for
probabilistic inference problems. This paper proposes and analyzes a
generalization of Opper and Winther's expectation consistent (EC) approximate
inference method. The proposed method, called Generalized Expectation
Consistency (GEC), can be applied to both maximum a posteriori (MAP) and
minimum mean squared error (MMSE) estimation. Here we characterize its fixed
points, convergence, and performance relative to the replica prediction of
optimality.


title: Probe Machine

abstract:
  A novel computing model, called \emph{Probe Machine}, is proposed in this
paper. Different from Turing Machine, Probe Machine is a fully-parallel
computing model in the sense that it can simultaneously process multiple pairs
of data, rather than sequentially process every pair of linearly-adjacent data.
In this paper, we establish the mathematical model of Probe Machine as a
9-tuple consisting of data library, probe library, data controller, probe
controller, probe operation, computing platform, detector, true solution
storage, and residue collector. We analyze the computation capability of the
Probe Machine model, and in particular we show that Turing Machine is a special
case of Probe Machine. We revisit two NP-complete problems---i.e., the Graph
Coloring and Hamilton Cycle problems, and devise two algorithms on basis of the
established Probe Machine model, which can enumerate all solutions to each of
these problems by only one probe operation. Furthermore, we show that Probe
Machine can be implemented by leveraging the nano-DNA probe technologies. The
computational power of an electronic computer based on Turing Machine is known
far more than that of the human brain. A question naturally arises: will a
future computer based on Probe Machine outperform the human brain in more ways
beyond the computational power?


title: $\Lambda_c-N$ interaction from lattice QCD

abstract:
  We investigate the s-wave $\Lambda_c-N$ interaction for spin singlet
systems($^1S_0$) using the HAL QCD method. In our lattice QCD simulations, we
employ gauge configurations generated by the PACS-CS Collaboration at $a =
0.0907(13)$ fm on a $32^3 \times 64$ lattice ($La = 2.902(42)$ fm). We employ
two ensembles, one at $m_\pi = 700(1)$ MeV and the other at $m_\pi = 570(1)$
MeV to study the quark mass dependence of the $\Lambda_c-N$ interactions. We
calculate a $^1S_0$ central potential not only for the $\Lambda_c-N$ system but
also for $\Lambda-N$ system to understand the role of heavy charm quarks in
$\Lambda_c-N$ system. We find repulsion at short distance and attraction at
mid-range for both the $\Lambda_c-N$ and the $\Lambda-N$ potentials. The short
range repulsion of the $\Lambda_c-N$ potential is smaller than that of the
$\Lambda-N$ potential, and the attraction of the $\Lambda_c-N$ potential is
small compared with the $\Lambda-N$ potential. The phase shift and scattering
length calculated with these potentials show that there exist no bound state
for both the $\Lambda_c-N$ and $\Lambda-N$ systems for $m_{\pi} > 570$ MeV.


title:
Structural studies of eight bright rimmed clouds in the southern
  hemisphere

abstract:
  We carried out deep and wide-field near- and mid-infrared observations for a
sample of 8 bright-rimmed clouds (BRCs). Supplemented with the $Spitzer$
archival data, we have identified and classified 44 to 433 young stellar
objects (YSOs) associated with these BRCs. The Class I sources are generally
located towards the places with higher extinction and are relatively closer to
each other than the Class II sources, confirming that the young protostars are
usually found in regions having denser molecular material. On the other hand
the comparatively older population, Class II objects, are more randomly found
throughout the regions, which can be due to their dynamical evolution. Using
the minimal sampling tree analyses, we have extracted 13 stellar cores of 8 or
more members, which contains 60\% of the total YSOs. The typical core is
$\sim$0.6 pc in radii and somewhat elongated (aspect ratio of 1.45), of
relatively low stellar density (surface density 60 pc$^{-2}$), consisting of a
small (35) number of YSOs of relatively young sources (66\% Class I ), and
partially embedded (median $A_K$ =1.1 mag). But the cores show a wide range in
their mass distribution ($\sim$20 to 2400 M$_\odot$) with a median value of
around 130 M$_\odot$. We have found the star formation efficiencies in the
cores to be between 3\% and 30\% with an average of $\sim$14\%, which agree
with the efficiencies needed to link the core mass function to the initial mass
function. We also found a linear relation between the density of the clouds and
the number of YSOs. The peaked nearest neighbor spacing distributions of the
YSOs and the ratio of Jeans lengths to the YSOs separations indicates a
significant degree of non-thermally driven fragmentation in these BRCs.


title: A Study on the usage of Data Structures in Information Retrieval

abstract:
  This paper tries to throw light in the usage of data structures in the field
of information retrieval. Information retrieval is an area of study which is
gaining momentum as the need and urge for sharing and exploring information is
growing day by day. Data structures have been the area of research for a long
period in the arena of computer science. The need to have efficient data
structures has become even more important as the data grows in an exponential
nature.


title: Towards Unifying Hamiltonian Monte Carlo and Slice Sampling

abstract:
  We unify slice sampling and Hamiltonian Monte Carlo (HMC) sampling,
demonstrating their connection via the Hamiltonian-Jacobi equation from
Hamiltonian mechanics. This insight enables extension of HMC and slice sampling
to a broader family of samplers, called Monomial Gamma Samplers (MGS). We
provide a theoretical analysis of the mixing performance of such samplers,
proving that in the limit of a single parameter, the MGS draws decorrelated
samples from the desired target distribution. We further show that as this
parameter tends toward this limit, performance gains are achieved at a cost of
increasing numerical difficulty and some practical convergence issues. Our
theoretical results are validated with synthetic data and real-world
applications.


title:
Investigating multi-channel quantum tunneling in heavy-ion fusion
  reactions with Bayesian spectral deconvolution

abstract:
  Excitations of colliding nuclei during a nuclear reaction considerably affect
fusion cross sections at energies around the Coulomb barrier. It has been
demonstrated that such channel coupling effects can be represented in terms of
a distribution of multiple fusion barriers. We here apply a Bayesian approach
to analyze the so called fusion barrier distributions. This method determines
simultaneously the barrier parameters and the number of barriers. We
particularly investigate the $^{16}$O+$^{144}$Sm and $^{16}$O+$^{154}$Sm
systems in order to demonstrate the effectiveness of the method. The present
analysis indicates that the fusion barrier distribution for the former system
is most consistent with three fusion barriers, even though the experimental
data show only two distinct peaks.


title:
Beating the SDP bound for the floor layout problem: A simple
  combinatorial idea

abstract:
  For many mixed-integer programming (MIP) problems, high-quality dual bounds
can be obtained either through advanced formulation techniques coupled with a
state-of-the-art MIP solver, or through semidefinite programming (SDP)
relaxation hierarchies. In this paper, we introduce an alternative bounding
approach that exploits the "combinatorial implosion" effect by solving portions
of the original problem and aggregating this information to obtain a global
dual bound. We apply this technique to the one-dimensional and two-dimensional
floor layout problems and compare it with the bounds generated by both
state-of-the-art MIP solvers and by SDP relaxations. Specifically, we prove
that the bounds obtained through the proposed technique are at least as good as
those obtained through SDP relaxations, and present computational results that
these bounds can be significantly stronger and easier to compute than these
alternative strategies, particularly for very difficult problem instances.


title:
Automated Word Prediction in Bangla Language Using Stochastic Language
  Models

abstract:
  Word completion and word prediction are two important phenomena in typing
that benefit users who type using keyboard or other similar devices. They can
have profound impact on the typing of disable people. Our work is based on word
prediction on Bangla sentence by using stochastic, i.e. N-gram language model
such as unigram, bigram, trigram, deleted Interpolation and backoff models for
auto completing a sentence by predicting a correct word in a sentence which
saves time and keystrokes of typing and also reduces misspelling. We use large
data corpus of Bangla language of different word types to predict correct word
with the accuracy as much as possible. We have found promising results. We hope
that our work will impact on the baseline for automated Bangla typing.


title:
Silicide Induced Surface Defects in FePt nanoParticle fcc-to-fct
  Thermally Activated Phase Transition

abstract:
  Magnetic nanoparticles (MnPs) are relevant to a wide range of applications
including high density information storage and magnetic resonance imaging to
name but a few. Among the materials available to prepare MnPs, FePt is
attracting growing attention. However, to harvest the strongest magnetic
properties of FePt MnPs, a thermal annealing is often required to convert
face-centered cubic as synthesized nPs into its tetragonal phase. Rarely
addressed are the potential side effects of such treatments on the magnetic
properties. In this study, we focus on the impact of silica shells often used
in strategies aiming at overcoming MnP coalescence during the thermal
annealing. While we show that this shell does prevent sintering, and that
fcc-to-fct conversion does occur, we also reveal the formation of silicide,
which can prevent the stronger magnetic properties of fct-FePt MnPs from being
fully realised. This report therefore sheds lights on poorly investigated and
understood interfacial phenomena occurring during the thermal annealing of MnPs
and, by doing so, also highlights the benefits of developing new strategies to
avoid silicide formation.


title:
X-ray Observations of Bow Shocks around Runaway O Stars. The case of
  $\zeta$ Oph and BD+43$^{\circ}$3654

abstract:
  Non-thermal radiation has been predicted within bow shocks around runaway
stars by recent theoretical works. We present X-ray observations towards the
runaway stars $\zeta$ Oph (Chandra and Suzaku) and BD+43$^{\circ}$3654
(XMM-Newton) to search for the presence of non-thermal X-ray emission. We found
no evidence of non-thermal emission spatially coincident with the bow shocks,
nonetheless, diffuse emission is detected in the vicinity of $\zeta$ Oph. After
a careful analysis of its spectral characteristics we conclude that this
emission has a thermal nature with a plasma temperature of $T \approx 2
\times10^{6}$ K. The cometary shape of this emission seems to be in line with
recent predictions of radiation-hydrodynamic models of runaway stars. The case
of BD+43$^{\circ}$3654 is puzzling as non-thermal emission has been reported in
a previous work for this source.


title:
Lipschitz regularity for integro-differential equations with coercive
  hamiltonians and application to large time behavior

abstract:
  In this paper, we provide suitable adaptations of the "weak version of
Bernstein method" introduced by the first author in 1991, in order to obtain
Lipschitz regularity results and Lipschitz estimates for nonlinear
integro-differential elliptic and parabolic equations set in the whole space.
Our interest is to obtain such Lipschitz results to possibly degenerate
equations, or to equations which are indeed "uniformly el-liptic" (maybe in the
nonlocal sense) but which do not satisfy the usual "growth condition" on the
gradient term allowing to use (for example) the Ishii-Lions' method. We treat
the case of a model equation with a superlinear coercivity on the gradient term
which has a leading role in the equation. This regularity result together with
comparison principle provided for the problem allow to obtain the ergodic large
time behavior of the evolution problem in the periodic setting.


title:
Data Cleaning for XML Electronic Dictionaries via Statistical Anomaly
  Detection

abstract:
  Many important forms of data are stored digitally in XML format. Errors can
occur in the textual content of the data in the fields of the XML. Fixing these
errors manually is time-consuming and expensive, especially for large amounts
of data. There is increasing interest in the research, development, and use of
automated techniques for assisting with data cleaning. Electronic dictionaries
are an important form of data frequently stored in XML format that frequently
have errors introduced through a mixture of manual typographical entry errors
and optical character recognition errors. In this paper we describe methods for
flagging statistical anomalies as likely errors in electronic dictionaries
stored in XML format. We describe six systems based on different sources of
information. The systems detect errors using various signals in the data
including uncommon characters, text length, character-based language models,
word-based language models, tied-field length ratios, and tied-field
transliteration models. Four of the systems detect errors based on expectations
automatically inferred from content within elements of a single field type. We
call these single-field systems. Two of the systems detect errors based on
correspondence expectations automatically inferred from content within elements
of multiple related field types. We call these tied-field systems. For each
system, we provide an intuitive analysis of the type of error that it is
successful at detecting. Finally, we describe two larger-scale evaluations
using crowdsourcing with Amazon's Mechanical Turk platform and using the
annotations of a domain expert. The evaluations consistently show that the
systems are useful for improving the efficiency with which errors in XML
electronic dictionaries can be detected.


title:
"Resource Pooling" for Wireless Networks: Solutions for the Developing
  World

abstract:
  We live in a world in which there is a great disparity between the lives of
the rich and the poor. Technology offers great promise in bridging this gap. In
particular, wireless technology unfetters developing communities from the
constraints of infrastructure providing a great opportunity to leapfrog years
of neglect and technological waywardness. In this paper, we highlight the role
of resource pooling for wireless networks in the developing world. Resource
pooling involves: (i) abstracting a collection of networked resources to behave
like a single unified resource pool and (ii) developing mechanisms for shifting
load between the various parts of the unified resource pool. The popularity of
resource pooling stems from its ability to provide resilience, high
utilization, and flexibility at an acceptable cost. We show that "resource
pooling", which is very popular in its various manifestations, is the key
unifying principle underlying a diverse number of successful wireless
technologies (such as white space networking, community networks, etc.). We
discuss various applications of resource pooled wireless technologies and
provide a discussion on open issues.


title: Entropy of Isometries Semi-groups of Hyperbolic space

abstract:
  We give a generalization to convex co-compact semigroups of a beautiful
theorem of Patterson-Sullivan, telling that the critical exponent (that is the
exponential growth rate) equals the Hausdorff dimension of the limit set (that
is the smallest closed non-empty invariant subset), for a isometries discrete
group of a proper hyperbolic space with compact boundary. To do that, we
introduce a notion of entropy, which generalize the notion of critical exponent
of discrete groups, and we show that it is equal to the upper bound of critical
exponents of Schottky sub-semigroups (which are semigroups having the simplest
dynamic). We obtains several others corollaries, such that the lower
semi-continuity of the entropy, the fact that the critical exponent of a
separate semigroup, that is defined as an upper limit, is in fact a true limit,
and we obtain the existence of "big" Schottky sub-semigroups in discrete groups
of isometries.


title: Big Data For Development: Applications and Techniques

abstract:
  With the explosion of social media sites and proliferation of digital
computing devices and Internet access, massive amounts of public data is being
generated on a daily basis. Efficient techniques/ algorithms to analyze this
massive amount of data can provide near real-time information about emerging
trends and provide early warning in case of an imminent emergency (such as the
outbreak of a viral disease). In addition, careful mining of these data can
reveal many useful indicators of socioeconomic and political events, which can
help in establishing effective public policies. The focus of this study is to
review the application of big data analytics for the purpose of human
development. The emerging ability to use big data techniques for development
(BD4D) promises to revolutionalize healthcare, education, and agriculture;
facilitate the alleviation of poverty; and help to deal with humanitarian
crises and violent conflicts. Besides all the benefits, the large-scale
deployment of BD4D is beset with several challenges due to the massive size,
fast-changing and diverse nature of big data. The most pressing concerns relate
to efficient data acquisition and sharing, establishing of context (e.g.,
geolocation and time) and veracity of a dataset, and ensuring appropriate
privacy. In this study, we provide a review of existing BD4D work to study the
impact of big data on the development of society. In addition to reviewing the
important works, we also highlight important challenges and open issues.


title:
Narrative Smoothing: Dynamic Conversational Network for the Analysis of
  TV Series Plots

abstract:
  Modern popular TV series often develop complex storylines spanning several
seasons, but are usually watched in quite a discontinuous way. As a result, the
viewer generally needs a comprehensive summary of the previous season plot
before the new one starts. The generation of such summaries requires first to
identify and characterize the dynamics of the series subplots. One way of doing
so is to study the underlying social network of interactions between the
characters involved in the narrative. The standard tools used in the Social
Networks Analysis field to extract such a network rely on an integration of
time, either over the whole considered period, or as a sequence of several
time-slices. However, they turn out to be inappropriate in the case of TV
series, due to the fact the scenes showed onscreen alternatively focus on
parallel storylines, and do not necessarily respect a traditional chronology.
This makes existing extraction methods inefficient to describe the dynamics of
relationships between characters, or to get a relevant instantaneous view of
the current social state in the plot. This is especially true for characters
shown as interacting with each other at some previous point in the plot but
temporarily neglected by the narrative. In this article, we introduce narrative
smoothing, a novel, still exploratory, network extraction method. It smooths
the relationship dynamics based on the plot properties, aiming at solving some
of the limitations present in the standard approaches. In order to assess our
method, we apply it to a new corpus of 3 popular TV series, and compare it to
both standard approaches. Our results are promising, showing narrative
smoothing leads to more relevant observations when it comes to the
characterization of the protagonists and their relationships. It could be used
as a basis for further modeling the intertwined storylines constituting TV
series plots.


title:
Symmetry-breaking bifurcation for the one-dimensional Liouville type
  equation

abstract:
  The two-point boundary value problem for the one-dimensional Liouville type
equation is considered. In this paper, a symmetry-breaking result is obtained
by using the Morse index.


title: Crisis Analytics: Big Data Driven Crisis Response

abstract:
  Disasters have long been a scourge for humanity. With the advances in
technology (in terms of computing, communications, and the ability to process
and analyze big data), our ability to respond to disasters is at an inflection
point. There is great optimism that big data tools can be leveraged to process
the large amounts of crisis-related data (in the form of user generated data in
addition to the traditional humanitarian data) to provide an insight into the
fast-changing situation and help drive an effective disaster response. This
article introduces the history and the future of big crisis data analytics,
along with a discussion on its promise, challenges, and pitfalls.


title: Numerical study of the critical phases of the frustrated Z(5) model

abstract:
  The phase diagram of the $\mathbb{Z}(5)$ spin model is studied numerically on
the square lattice by means of the {\sl Density Matrix Renormalization Group}.
In the regime where the two nearest-neighbor couplings have opposite signs, a
critical phase, not observed in earlier Monte Carlo simulations, is identified.
The new phase diagram is in agreement with predictions made by M. den Nijs
[{\sl Phys. Rev. B} {\bf 31}, 266 (1985)] but for the $\mathbb{Z}(7)$ model
rather than the $\mathbb{Z}(5)$ one. All critical phases are shown to be
compatible with a central charge $c=1$. The magnetization scaling dimension
displays however a different behavior in the different critical phases.


title:
Dependence of stellar magnetic activity cycles on rotational period in
  nonlinear solar-type dynamo

abstract:
  We study turbulent generation of large-scale magnetic fields using nonlinear
dynamo models for solar-type stars in the range of rotational periods from 14
to 30 days. Our models take into account non-linear effects of dynamical
quenching of magnetic helicity, and escape of magnetic field from the dynamo
region due to magnetic buoyancy. The results show that the observed correlation
between the period of rotation and the duration of activity cycles can be
explained in the framework of a distributed dynamo model with a dynamical
magnetic feedback acting on the turbulent generation either from magnetic
buoyancy or magnetic helicity. We discuss implications of our findings for the
understanding of dynamo processes operating in solar-like stars.


title: Relating Graph Thickness to Planar Layers and Bend Complexity

abstract:
  The thickness of a graph $G=(V,E)$ with $n$ vertices is the minimum number of
planar subgraphs of $G$ whose union is $G$. A polyline drawing of $G$ in
$\mathbb{R}^2$ is a drawing $\Gamma$ of $G$, where each vertex is mapped to a
point and each edge is mapped to a polygonal chain. Bend and layer complexities
are two important aesthetics of such a drawing. The bend complexity of $\Gamma$
is the maximum number of bends per edge in $\Gamma$, and the layer complexity
of $\Gamma$ is the minimum integer $r$ such that the set of polygonal chains in
$\Gamma$ can be partitioned into $r$ disjoint sets, where each set corresponds
to a planar polyline drawing. Let $G$ be a graph of thickness $t$. By
F\'{a}ry's theorem, if $t=1$, then $G$ can be drawn on a single layer with bend
complexity $0$. A few extensions to higher thickness are known, e.g., if $t=2$
(resp., $t>2$), then $G$ can be drawn on $t$ layers with bend complexity 2
(resp., $3n+O(1)$). However, allowing a higher number of layers may reduce the
bend complexity, e.g., complete graphs require $\Theta(n)$ layers to be drawn
using 0 bends per edge.
  In this paper we present an elegant extension of F\'{a}ry's theorem to draw
graphs of thickness $t>2$. We first prove that thickness-$t$ graphs can be
drawn on $t$ layers with $2.25n+O(1)$ bends per edge. We then develop another
technique to draw thickness-$t$ graphs on $t$ layers with bend complexity,
i.e., $O(\sqrt{2}^{t} \cdot n^{1-(1/\beta)})$, where $\beta = 2^{\lceil (t-2)/2
\rceil }$. Previously, the bend complexity was not known to be sublinear for
$t>2$. Finally, we show that graphs with linear arboricity $k$ can be drawn on
$k$ layers with bend complexity $\frac{3(k-1)n}{(4k-2)}$.


title: Electronic Spin Transport in Dual-Gated Bilayer Graphene

abstract:
  The elimination of extrinsic sources of spin relaxation is key in realizing
the exceptional intrinsic spin transport performance of graphene. Towards this,
we study charge and spin transport in bilayer graphene-based spin valve devices
fabricated in a new device architecture which allows us to make a comparative
study by separately investigating the roles of substrate and polymer residues
on spin relaxation. First, the comparison between spin valves fabricated on
SiO2 and BN substrates suggests that substrate-related charged impurities,
phonons and roughness do not limit the spin transport in current devices. Next,
the observation of a 5-fold enhancement in spin relaxation time in the
encapsulated device highlights the significance of polymer residues on spin
relaxation. We observe a spin relaxation length of ~ 10 um in the encapsulated
bilayer with a charge mobility of 24000 cm2/Vs. The carrier density dependence
of spin relaxation time has two distinct regimes; n<4 x 1012 cm-2, where spin
relaxation time decreases monotonically as carrier concentration increases, and
n>4 x 1012 cm-2, where spin relaxation time exhibits a sudden increase. The
sudden increase in the spin relaxation time with no corresponding signature in
the charge transport suggests the presence of a magnetic resonance close to the
charge neutrality point. We also demonstrate, for the first time, spin
transport across bipolar p-n junctions in our dual-gated device architecture
that fully integrates a sequence of encapsulated regions in its design. At low
temperatures, strong suppression of the spin signal was observed while a
transport gap was induced, which is interpreted as a novel manifestation of
impedance mismatch within the spin channel.


title: Coupling the Inflationary Sector to Matter

abstract:
  We describe the coupling of matter fields to an inflationary sector of
supergravity, the inflaton $\Phi$ and a stabilizer $S$, in models where the
Kahler potential has a flat inflaton direction. Such models include, in
particular, advanced versions of the hyperbolic $\alpha$-attractor models with
a flat inflaton direction Kahler potential, providing a good fit to the
observational data. If the superpotential is at least quadratic in the matter
fields $U^{i}$, with restricted couplings to the inflaton sector, we prove that
under certain conditions: i) The presence of the matter fields does not affect
a successful inflationary evolution. ii) There are no tachyons in the matter
sector during and after inflation. iii) The matter masses squared are higher
than $3H^2$ during inflation. The simplest class of theories satisfying all
required conditions is provided by models with a flat direction Kahler
potential, and with the inflaton $\Phi$ and a stabilizer $S$ belonging to a
hidden sector, so that matter fields have no direct coupling to the
inflationary sector in the Kahler potential and in the superpotential.


title:
SOCP Reformulation for the Generalized Trust Region Subproblem via a
  Canonical Form of Two Symmetric Matrices

abstract:
  We investigate in this paper the generalized trust region subproblem (GTRS)
of minimizing a general quadratic objective function subject to a general
quadratic inequality constraint. By applying a simultaneous block
diagonalization approach, we obtain a congruent canonical form for the
symmetric matrices in both the objective and constraint functions. By
exploiting the block separability of the canonical form, we show that all GTRSs
with an optimal value bounded from below are second order cone programming
(SOCP) representable. Our result generalizes the recent work of Ben-Tal and
Hertog (Math. Program. 143(1-2):1-29, 2014), which establishes the SOCP
representability of the GTRS under the assumption of the simultaneous
diagonalizability of the two matrices in the objective and constraint
functions. Compared with the state-of-the-art approach to reformulate the GTRS
as a semi-definite programming problem, our SOCP reformulation delivers a much
faster solution algorithm. We further extend our method to two variants of the
GTRS in which the inequality constraint is replaced by either an equality
constraint or an interval constraint. Our methods also enable us to obtain
simplified versions of the classical S-lemma, the S-lemma with equality, and
the S-lemma with interval bounds.


title: Coherent Pion Production in Neutrino Nucleus Scattering

abstract:
  In this article, we study the coherent pion production in neutrino-nucleus
interaction in the resonance region using the formalism based on partially
conserved axial current (PCAC) theorem which relates the neutrino-nucleus cross
section to the pion-nucleus elastic cross section. The pion nucleus elastic
cross section is calculated using the Glauber model in terms of pion-nucleon
cross sections obtained by parameterizing the experimental data. We calculate
the differential and integrated cross sections for charged current coherent
pion production in neutrino carbon scattering. The results of integrated cross
section calculations are compared with the measured data. Predictions for the
differential and integrated cross sections for coherent pion productions in
neutrino iron scattering using above formalism are also made.


title:
Radially excited axial mesons and the enigmatic $Z_c$ and $Z_b$ in a
  coupled-channel model

abstract:
  The enigmatic charged states $Z_c(3900)$, $Z_c(4020)$, $Z_c(4050)$,
$Z_b(10610)$, and $Z_b(10650)$ are studied within a coupled-channel
Schr\"odinger model, where radially excited quark-antiquark pairs, with the
same angular momenta and isospin as the $a_1(1260)$ and $b_1(1235)$, are
strongly coupled to their Okubo-Zweig-Iizuka - allowed decay channels
$D\bar{D}^*+\bar{D}D^*$ and $D^*\bar{D}^*$, or $B\bar{B}^*+\bar{B}B^*$ and
$B^*\bar{B}^*$, in $S$ and $D$-wave. Poles, matching the experimental mass and
width of all the above states, are found by varying only two free parameters.
From the wave-function analysis of each resonance, the probability of each of
the components contributing to the coupled system is estimated, and predictions
can be made for the relative decay fractions among the coupled open-charm or
open-bottom decay channels.


title:
Large-scale shell-model analysis of the neutrinoless $\beta\beta$ decay
  of $^{48}$Ca

abstract:
  We present the nuclear matrix element for the neutrinoless double-beta decay
of $^{48}$Ca based on large-scale shell-model calculations including two
harmonic oscillator shells ($sd$ and $pf$ shells). The excitation spectra of
$^{48}$Ca and $^{48}$Ti, and the two-neutrino double-beta decay of $^{48}$Ca
are reproduced in good agreement to experiment. We find that the neutrinoless
double-beta decay nuclear matrix element is enhanced by about 30\% compared to
$pf$-shell calculations. This reduces the decay lifetime by almost a factor of
two. The matrix-element increase is mostly due to pairing correlations
associated with cross-shell $sd$-$pf$ excitations. We also investigate possible
implications for heavier neutrinoless double-beta decay candidates.


title: Generation of nonlinear vortex precursors

abstract:
  We numerically study the propagation of a few-cycle pulse carrying orbital
angular momentum (OAM) through a dense atomic system. Nonlinear precursors
consisting of high-order vortex har- monics are generated in the transmitted
field due to ultrafast Bloch oscillation. The nonlinear precursors survive to
propagation effects and are well separated with the main pulse, which provide a
straightforward way of measuring precursors. By the virtue of carrying
high-order OAM, the obtained vortex precursors as information carriers have
potential applications in optical informa- tion and communication fields where
controllable loss, large information-carrying capacity and high speed
communication are required.


title:
Eigenvalues under the backward Ricci flow on locally homogeneous closed
  3-manifolds

abstract:
  In this paper, we study the evolving behaviors of the first eigenvalue of
Laplace-Beltrami operator under the normalized backward Ricci flow, construct
various quantities which are monotonic under the backward Ricci flow and get
upper and lower bounds. We prove that in cases where the backward Ricci flow
converges to a sub-Riemannian geometry after a proper rescaling, the eigenvalue
evolves toward zero.


title:
Mean-Field Stochastic Linear Quadratic Optimal Control Problems:
  Closed-Loop Solvability

abstract:
  An optimal control problem is studied for a linear mean-field stochastic
differential equation with a quadratic cost functional. The coefficients and
the weighting matrices in the cost functional are all assumed to be
deterministic. Closed-loop strategies are introduced, which require to be
independent of initial states; and such a nature makes it very useful and
convenient in applications. In this paper, the existence of an optimal
closed-loop strategy for the system (also called the closed-loop solvability of
the problem) is characterized by the existence of a regular solution to the
coupled two (generalized) Riccati equations, together with some constraints on
the adapted solution to a linear backward stochastic differential equation and
a linear terminal value problem of an ordinary differential equation.


title: Atomistic modeling of the anomalous helium behaviors in vanadium

abstract:
  Ab initio calculations have been performed to clarify the primary behaviors
of He atoms in vanadium and to generate the database for the development of the
interatomic potential for V-He system within the framework of
the"s-band"model.The calculated formation energies of the
tetrahedral,octahedral and substitutional He defects,as well as those for
He2,He3 and He2V clusters are reasonable when compared with relevant
experimental results and ab initio calculations under the same conditions.The
applicability of the present V-He potential for atomistic simulations to
investigate the moving,clustering,and trapping of interstitial He atoms in
vanadium are demonstrated.Similar to the results in iron and tungsten,the
interstitial He atoms can migrate quickly in vanadium. However,He atoms
aggregate into clusters with low binding energies,and the trapping of He atoms
depend much on the pre-existing traps in vanadium.


title: Minimum Cost Homomorphisms with Constrained Costs

abstract:
  Minimum cost homomorphism problems can be viewed as a generalization of list
homomorphism problems. They also extend two well-known graph colouring
problems: the minimum colour sum problem and the optimum cost chromatic
partition problem. In both of these problems, the cost function meets an
additional constraint: the cost of using a specific colour is the same for
every vertex of the input graph. We study minimum cost homomorphism problems
with cost functions constrained to have this property. Clearly, when the
standard minimum cost homomorphism problem is polynomial, then the problem with
constrained costs is also polynomial. We expect that the same may hold for the
cases when the standard minimum cost homomorphism problem is NP-complete. We
prove that this is the case for trees $H$: we obtain a dichotomy of minimum
constrained cost homomorphism problems which coincides with the dichotomy of
standard minimum cost homomorphism problems. For general graphs $H$, we prove a
partial dichotomy: the problem is polynomial if $H$ is a proper interval graph
and NP-complete when $H$ is not chordal bipartite.


title: State pseudo equality algebras

abstract:
  Pseudo equality algebras were initially introduced by Jenei and $\rm
K\acute{o}r\acute{o}di$ as a possible algebraic semantic for fuzzy type theory,
and they have been revised by Dvure\v censkij and Zahiri under the name of
JK-algebras. The aim of this paper is to investigate the internal states and
the state-morphisms on pseudo equality algebras. We define and study new
classes of pseudo equality algebras, such as commutative, symmetric, pointed
and compatible pseudo equality algebras. We prove that any internal state
(state-morphism) on a pseudo equality algebra is also an internal state
(state-morphism) on its corresponding pseudo BCK(pC)-meet-semilattice, and we
prove the converse for the case of linearly ordered symmetric pseudo equality
algebras. We also show that any internal state (state-morphism) on a pseudo
BCK(pC)-meet-semilattice is also an internal state (state-morphism) on its
corresponding pseudo equality algebra. The notion of a Bosbach state on a
pointed pseudo equality algebra is introduced and proved that any Bosbach state
on a pointed pseudo equality algebra is also a Bosbach state on its
corresponding pointed pseudo BCK(pC)-meet-semilattice. For the case of an
invariant pointed pseudo equality algebra, we show that the Bosbach states on
the two structures coincide.


title:
The number of composition factors of order $p$ in completely reducible
  groups of characteristic $p$

abstract:
  Let $q$ be a power of a prime $p$ and let $G$ be a completely reducible
subgroup of $\mathrm{GL}(d,q)$. We prove that the number of composition factors
of $G$ that have prime order $p$ is at most $(\varepsilon_q d-1)/(p-1)$, where
$\varepsilon_q$ is a function of $q$ satisfying
$1\leqslant\varepsilon_q\leqslant 3/2$. For every $q$, we give examples showing
this bound is sharp infinitely often.


title:
Weighted vector-valued estimates for a non-standard Calder\'on-Zygmund
  operator

abstract:
  In this paper, the author considers the weighted vector-valued estimate for
the operator defined by $$T_Af(x)={\rm
p.\,v.}\int_{\mathbb{R}^n}\frac{\Omega(x-y)}{|x-y|^{n+1}}\big(A(x)-A(y)-\nabla
A(y)\big)f(y){\rm d}y,$$ and the corresponding maximal operator $T_A^*$, where
$\Omega$ is homogeneous of degree zero, has vanishing moment of order one, $A$
is a function in $\mathbb{R}^n$ such that $\nabla A\in {\rm
BMO}(\mathbb{R}^n)$. By a pointwise estimate for $\|\{T_Af_k(x)\}\|_{l^q}$ and
the weighted $L^p$ estimates for the sparse operator
$$\mathcal{A}_{\mathcal{S},\,L(\log
L)^\beta}f(x)=\sum_{Q\in\mathcal{S}}\|f\|_{L(\log L)^{\beta},\,Q}\chi_{Q}(x)
,$$ the author establishes some weak and endpoint quantitative weighted
vector-valued estimates for $T_A$ and $T_A^*$.


title:
Phase diagram and collective excitation in excitonic insulator: from the
  orbital physics viewpoint

abstract:
  Excitonic insulating system is studied from the viewpoints of the orbital
physics in strongly correlated electron systems. An effective model Hamiltonian
for low-energy electronic states is derived from the two-orbital Hubbard model
with a finite energy difference corresponding to the crystalline field
splitting. The effective model is represented by the spin operators and the
pseudo-spin operators for the spin-state degrees of freedom. The ground state
phase diagram is analyzed by the mean-field approximation. In addition to the
low-spin state and high-spin state phases, two kinds of the excitonic
insulating phases emerge as a consequence of the competition between the
crystalline field effect and the Hund coupling. The excitonic transition is
classified to be an Ising-like transition reflecting a spontaneous breaking of
the $Z_2$ symmetry. Magnetic structures in the two excitonic insulating phases
are different from each other; an antiferromagnetic order and a spin nematic
order. Collective excitations in each phase are examined by using the
generalized spin-wave method. The Goldstone modes in the excitonic insulating
phases appear in the dynamical correlation functions for the spins and
pseudo-spin operators. Both the transverse and longitudinal spin excitation
modes are active in the two excitonic insulating phases in contrast to the
low-spin state and high-spin state phases. Connections of the present results
to the perovskite cobalt oxides are discussed.


title:
Manipulation of light in a generalized coupled Nonlinear Schrodinger
  equation

abstract:
  We investigate a generalized coupled nonlinear Schrodinger (GCNLS) equation
containing Self-Phase Modulation (SPM), Cross-Phase Modulation (XPM) and Four
Wave Mixing (FWM) describing the propagation of electromagnetic radiation
through an optical fibre and generate the associated Lax-pair. We then
construct bright solitons employing gauge transformation approach. The
collisional dynamics of bright solitons indicates that it is not only possible
to manipulate intensity (energy) between the two modes (optical beams), but
also within a given mode unlike the Manakov model which does not have the same
freedom. The freedom to manipulate intensity (energy) in a given mode or
between two modes arises due to a suitable combination of SPM, XPM and
FWM.While SPM and XPM are controlled by an arbitrary real parameter each, FWM
is governed by two arbitrary complex parameters. The above model may have wider
ramifications in nonlinear optics and Bose-Einstein Condensates (BECs).


title: A fault-tolerant addressable spin qubit in a natural silicon quantum dot

abstract:
  Fault-tolerant quantum operation is a key requirement for the development of
quantum computing. This has been realized in various solid-state systems
including isotopically purified silicon which provides a nuclear spin free
environment for the qubits, but not in industry standard natural (unpurified)
silicon. Here we demonstrate an addressable fault-tolerant qubit using a
natural silicon double quantum dot with a micromagnet optimally designed for
fast spin control. This optimized design allows us to achieve the optimum Rabi
oscillation quality factor Q = 140 at a Rabi frequency of 10 MHz in the
frequency range two orders of magnitude higher than that achieved in previous
studies. This leads to a qubit fidelity of 99.6 %, which is the highest
reported for natural silicon qubits and comparable to that obtained in
isotopically purified silicon quantum-dot-based qubits. This result can inspire
contributions from the industrial and quantum computing communities.


title: Fluctuation capture in non-polar gases and liquids

abstract:
  We present a new model to identify natural fluctuations in fluids, allowing
us to describe localization phenomena in the transport of electrons, positrons
and positronium through non-polar fluids. The theory contains no free
parameters and allows for the calculation of capture cross sections
$\sigma_{cap}(\epsilon)$ of light-particles in any non-polar fluid, required
for non-equilibrium transport simulations. We postulate that localization
occurs through large shallow traps before stable bound states are formed. Our
results allow us to explain most of the experimental observations of changes in
mobility and annihilation rates in the noble gases and liquids as well as make
predictions for future experiments. Quantities which are currently inaccessible
to experiment, such as positron mobilities, can be obtained from our theory.
Unlike other theoretical approaches to localization, the outputs of our theory
can be applied in non-equilibrium transport simulations and an extension to the
determination of waiting time distributions for localized states is straight
forward.


title: Constraints on the Photon Mass with Fast Radio Bursts

abstract:
  Fast radio bursts (FRBs) are radio bursts characterized by millisecond
durations, high Galactic latitude positions, and high dispersion measures. Very
recently, the cosmological origin of FRB 150418 has been confirmed by
\cite{kea16}, and FRBs are now strong competitors as cosmological probes. The
simple sharp feature of the FRB signal is ideal for them to probe some of the
fundamental laws of physics. Here we show that by analyzing the delay time
between different frequencies, the FRB data can place stringent upper limits on
the rest mass of the photon. For FRB 150418 at $z=0.492$, one can potentially
reach $m_{\gamma} \leq 5.2 \times 10^{-47}$ g, which is $10^{20}$ times smaller
than the rest mass of electron, and is about $10^3$ times smaller than that
obtained using other astrophysical sources with the same method.


title: A Bayesian baseline for belief in uncommon events

abstract:
  The plausibility of uncommon events and miracles based on testimony of such
an event has been much discussed. When analyzing the probabilities involved, it
has mostly been assumed that the common events can be taken as data in the
calculations. However, we usually have only testimonies for the common events.
While this difference does not have a significant effect on the inductive part
of the inference, it has a large influence on how one should view the
reliability of testimonies. In this work, a full Bayesian solution is given for
the more realistic case, where one has a large number of testimonies for a
common event and one testimony for an uncommon event. It is seen that, in order
for there to be a large amount of testimonies for a common event, the
testimonies will probably be quite reliable. For this reason, because the
testimonies are quite reliable based on the testimonies for the common events,
the probability for the uncommon event, given a testimony for it, is also
higher. Hence, one should be more open-minded when considering the plausibility
of uncommon events.


title: (p,q)-deformed Virasoro-Witt n-algebra

abstract:
  n-ary algebras have played important roles in mathematics and mathematical
physics. The purpose of this paper is to construct a deformation of
Virasoro-Witt n-algebra based on an oscillator realization with two independent
parameters (p, q) and investigate its n-Lie subalgebra.


title: Visualizing Class Information

abstract:
  A class is used in object oriented programming to describe each object in the
system. It is as a template contains the methods and attributes for each
object. The volume of information within the class has a role in the time
required for its implementation, testing and understanding the class.
Developers are dealing with large projects that contain a large number of Lines
Of Code (LOC). So that, extracting information about the classes requires time
and big effort from the developers. To solve this problem, we present a
visualization approach to display class information for developers. Our method
assumed each class is a cone chart and each cone represents one of the class
metrics that include number of methods, attributes and the number of Lines Of
Code (LOC). The height of each cone indicates the total number of methods,
attributes and number of Lines Of Code (LOC) which found in a class. Also, each
cone has a different color from the other to facilitate the distinction among
them


title: Tight bounds on discrete quantitative Helly numbers

abstract:
  Given a subset S of R^n, let c(S,k) be the smallest number t such that
whenever finitely many convex sets have exactly k common points in S, there
exist at most t of these sets that already have exactly k common points in S.
For S = Z^n, this number was introduced by Aliev et al. [2014] who gave an
explicit bound showing that c(Z^n,k) = O(k) holds for every fixed n. Recently,
Chestnut et al. [2015] improved this to c(Z^n,k) = O(k (log log k)(log
k)^{-1/3} ) and provided the lower bound c(Z^n,k) = Omega(k^{(n-1)/(n+1)}).
  We provide a combinatorial description of c(S,k) in terms of polytopes with
vertices in S and use it to improve the previously known bounds as follows: We
strengthen the bound of Aliev et al. [2014] by a constant factor and extend it
to general discrete sets S. We close the gap for Z^n by showing that c(Z^n,k) =
Theta(k^{(n-1)/(n+1)}) holds for every fixed n. Finally, we determine the exact
values of c(Z^n,k) for all k <= 4.


title:
Transition from non-sequential to sequential double ionisation in
  many-electron systems

abstract:
  Obtaining a detailed understanding of strong-field double ionisation of
many-electron systems (heavy atoms and molecules) remains a challenging task.
By comparing experimental and theoretical results in the mid-IR regime, we have
unambiguously identified the transition from non-sequential (e,2e) to
sequential double ionisation in Xe and shown that it occurs at an intensity
below $10^{14}$ Wcm$^{-2}$. In addition, our data demonstrate that ionisation
from the Xe 5s orbital is decisive at low intensities. Moreover, using the
acetylene molecule, we propose how sequential double ionisation in the mid-IR
can be used to study molecular dynamics and fragmentation on unprecedented
few-femtosecond timescales.


title: The Distance Measurement of NGC 1313 With Cepheids

abstract:
  We present the detection of Cepheids in the barred spiral galaxy NGC 1313,
using the Wide Field and Planetary Camera 2 on the Hubble Space Telescpoe.
Twenty B (F450W) and V (F555W) epochs of observations spanning over three weeks
were obtained, on which the profile-fitting photometry of all stars in the
monitored field was performed using the package HSTphot. A sample of 26
variable stars have been identified to be Cepheids, with periods between 3 and
14 days. Based on the derived period-luminosity relations in B and V bands, we
obtain an extinction-corrected distance modulus of mu = 28.32 +- 0.08 (random)
+- 0.06 (systematic), employing the Large Magellanic Cloud as the distance zero
point calibrator. The above moduli correspond to a distance of 4.61 +- 0.17
(random) +- 0.13 (systematic) Mpc, consistent with previous measurements
reported in the literature with uncertainties. In addition, the reddening to
NGC 1313 is found to be small.


title: Colossal dielectric constant in high entropy oxides

abstract:
  Entropic contributions to the stability of solids are very well understood
and the mixing entropy has been used for forming various solids, for instance
such as inverse spinels. A particular development was related to high entropy
alloys in which the configurational disorder is responsible for forming simple
solid solutions and which are thoroughly studied for various applications
especially due to their mechanical properties but also electrical properties,
hydrogen storage, magnetic properties. Many unexplored compositions and
properties still remain for this class of materials due to their large phase
space. In a recent report it has been shown that the configurational disorder
can be used for stabilizing simple solid solutions of oxides, which should
normally not form solid solutions, these new materials were called
"entropy-stabilized oxides". In this pioneering report, it was shown that
mixing five equimolar binary oxides yielded, after heating at high temperature
and quenching, an unexpected rock salt structure compound with statistical
distribution of the cations in a face centered cubic lattice. Following this
seminal study, we show here that these high entropy oxides (named HEOx
hereafter) can be substituted by aliovalent elements with a charge compensation
mechanism. This possibility largely increases the potential development of new
materials by widening their (already complex) phase space. As a first example,
we report here that at least one HEOx composition exhibits colossal dielectric
constants, which could make it very promising for applications as large-k
dielectric materials.


title:
Dearth of short-period Neptunian exoplanets - a desert in period-mass
  and period-radius planes

abstract:
  A few studies have reported a significant dearth of exoplanets with Neptune
mass and radius with orbital periods below $2$--$4$ d. This cannot be explained
by observational biases because many Neptunian planets with longer orbital
periods have been detected. The existence of this desert is similar to the
appearance of the so-called brown-dwarf desert that suggests different
formation mechanisms of planets and stellar companions with short orbital
periods. Similarly, the Neptunian desert might indicate different mechanisms of
formation and evolution for hot Jupiters and short-period super-Earths. We here
follow a previous study and examine the location and shape of the desert in
both the period-mass and period-radius planes, using the currently available
large samples of planets. The desert in the period-mass plane has a relatively
sharp upper edge, with a planetary mass that is inversely proportional to the
planetary orbital period, while the lower, somewhat blurred, boundary is
located along masses that are apparently linearly proportional to the period.
The desert in the period-radius plane of the transiting planets is less clear.
It seems as if the radius along the upper boundary is inversely proportional to
the period to the power of one-third, while the lower boundary shows a radius
that is proportional to the period to the power of two-thirds. The combination
of the two upper bounds of the desert, in the period-mass and period-radius
planes, yields a planetary mass-radius relation of $R_{\rm p}/R_{\rm Jup}\simeq
(1.2\pm0.3)(M_{\rm p}/M_{\rm Jup})^{0.27\pm0.11}\,$ for $ 0.1\lesssim M_{\rm
p}/M_{\rm Jup}\lesssim 1$. The derived shape of the desert, which might extend
up to periods of $5$--$10$ d, could shed some light on the formation and
evolution of close-in planets.


title: Fast Nonsmooth Regularized Risk Minimization with Continuation

abstract:
  In regularized risk minimization, the associated optimization problem becomes
particularly difficult when both the loss and regularizer are nonsmooth.
Existing approaches either have slow or unclear convergence properties, are
restricted to limited problem subclasses, or require careful setting of a
smoothing parameter. In this paper, we propose a continuation algorithm that is
applicable to a large class of nonsmooth regularized risk minimization
problems, can be flexibly used with a number of existing solvers for the
underlying smoothed subproblem, and with convergence results on the whole
algorithm rather than just one of its subproblems. In particular, when
accelerated solvers are used, the proposed algorithm achieves the fastest known
rates of $O(1/T^2)$ on strongly convex problems, and $O(1/T)$ on general convex
problems. Experiments on nonsmooth classification and regression tasks
demonstrate that the proposed algorithm outperforms the state-of-the-art.


title:
Continuous Functions as Quantum Operations: a probabilistic
  approximation

abstract:
  In this note we propose a version of the classical Stone-Weierstrass theorem
in the context of quantum operations, by introducing a particular class of
quantum operations, dubbed polynomial quantum operations. This result permits
to interpret from a probabilistic point of view, and up to a certain
approximation, any continuous function from the real cube [0; 1]^n to the real
interval [0; 1] as a quantum operation.


title:
A CP-violating phase in a two Higgs triplet scenario : some
  phenomenological implications

abstract:
  We consider a scenario where, along with the usual Higgs doublet, two scalar
triplets are present. The extension of the triplet sector is required for the
Type~II mechanism for the generation of neutrino masses, if this mechanism has
to generate a neutrino mass matrix with two-zero texture. One CP-violating
phase has been retained in the scalar potential of the model, and all
parameters have been chosen consistently with the observed neutrino mass and
mixing patterns. We find that a large phase ($\gtrsim 60^{\circ}$) splits the
two doubly-charged scalar mass eigenstates wider apart, so that the decay
$H_1^{++} \rightarrow H_2^{++} h$ is dominant (with h being the $125$ GeV
scalar). We identify a set of benchmark points where this decay dominates. This
is complementary to the situation, reported in our earlier work, where the
heavier doubly-charged scalar decays as $H_1^{++} \rightarrow H_2^+ W^+$. We
point out the rather spectacular signal, ensuing from $H_1^{++} \rightarrow
H_2^{++} h$, in the form of Higgs plus same-sign dilepton peak, which can be
observed at the Large Hadron Collider.


title: Generalized Casimir Operators

abstract:
  Let G be symmetrizable Kac-Moody Lie algebra. In this paper we describe a new
class of central operators generalising the Casimir operator. We also prove
some properties of these operators and show that these operators move highest
weight vectors to new highest weight vectors.


title:
Transiting Planet Candidates Beyond the Snow Line Detected by Visual
  Inspection of 7557 Kepler Objects of Interest

abstract:
  We visually inspected the light curves of 7557 Kepler Objects of Interest
(KOIs) to search for single transit events (STEs) possibly due to long-period
giant planets. We identified 28 STEs in 24 KOIs, among which 14 events are
newly reported in this paper. We estimate the radius and orbital period of the
objects causing STEs by fitting the STE light curves simultaneously with the
transits of the other planets in the system or with the prior information on
the host star density. As a result, we found that STEs in seven of those
systems are consistent with Neptune- to Jupiter-sized objects of orbital
periods ranging from a few to $\sim$ $20\,\mathrm{yr}$. We also estimate that
$\gtrsim20\%$ of the compact multi-transiting systems host cool giant planets
with periods $\gtrsim 3\,\mathrm{yr}$ on the basis of their occurrence in the
KOIs with multiple candidates, assuming the small mutual inclination between
inner and outer planetary orbits.


title: Modelling nova populations in galaxies

abstract:
  Theoretical modelling of the evolution of classical and recurrent novae plays
an important role in studies of binary evolution, nucleosynthesis and accretion
physics. However, from a theoretical perspective the observed statistical
properties of novae remain poorly understood. In this paper, we have produced
model populations of novae using a hybrid binary population synthesis approach
for differing star formation histories (SFHs): a starburst case
(elliptical-like galaxies), a constant star formation rate case (spiral-like
galaxies) and a composite case (in line with the inferred SFH for M31). We
found that the nova rate at 10\;Gyr in an elliptical-like galaxy is $\sim
10-20$ times smaller than a spiral-like galaxy with the same mass. The majority
of novae in elliptical-like galaxies at the present epoch are characterized by
low mass white dwarfs (WDs), long decay times, relatively faint absolute
magnitudes and long recurrence periods. In contrast, the majority of novae in
spiral-like galaxies at 10\;Gyr have massive WDs, short decay times, are
relatively bright and have short recurrence periods. The mass loss time
distribution for novae in our M31-like galaxy is in agreement with
observational data for Andromeda. However, it is possible that we underestimate
the number of bright novae in our model. This may arise in part due to the
present uncertainties in the appropriate bolometric correction for novae.


title: Elementary observations on Rogers-Szeg\"o polynomials

abstract:
  The Rogers-Szeg\"o polynomials are natural q-analogues of Newton binomials.
In general they have no closed expression. We consider some exceptional cases
which are products of a factor with a closed formula and another one with nice
values for q=1 and q=-1. These are related to normalized Rogers-Szeg\"o
polynomials which have nice expansions and Hankel determinants. The Exposition
of the paper is elementary and almost self-contained.


title:
Influence of morphological parameters in 3D composite materials on their
  effective thermal properties and comparison with effective mechanical
  properties

abstract:
  In this paper we study the effective thermal behaviour of 3D representative
volume elements (RVEs) of two-phased composite materials constituted by a
matrix with cylindrical and spherical inclusions distributed randomly, with
periodic boundaries. Variations around the shape of inclusions have been taken
into account, by corrugating shapes, excavating and/or by removing pieces of
inclusions. The effective behaviour is computed with the help of homogenization
process based on an accelerated FFT-scheme giving the thermal conductivity
tensor. Several morphological parameters are also taken into account for
instance the number and the volume fraction of each type of inclusions,... in
order to analyse the behaviour of the composite for a large number of
geometries. We compare the results obtained for RVEs with and without
variations, and then with the mechanical results of such composite studied in
our previous paper.


title: Entanglement of quantum circular states of light

abstract:
  We present a general approach to calculating the entanglement of formation
for superpositions of two-mode coherent states, placed equidistantly on a
circle in the phase space. We show that in the particular case of
rotationally-invariant circular states the Schmidt decomposition of two modes,
and therefore the value of their entanglement, are given by analytical
expressions. We analyse the dependence of the entanglement on the radius of the
circle and number of components in the superposition. We also show that the set
of rotationally-invariant circular states creates an orthonormal basis in the
state space of the harmonic oscillator, and this basis is advantageous for
representation of other circular states of light.


title:
Sublinear operators with rough kernel generated by fractional integrals
  and commutators on generalized vanishing local Morrey spaces

abstract:
  In this paper, we consider the norm inequalities for sublinear operators with
rough kernel generated by fractional integrals and commutators on generalized
local Morrey spaces and on generalized vanishing local Morrey spaces including
their weak versions under generic size conditions which are satisfied by most
of the operators in harmonic analysis, respectively. As an example to the
conditions of these theorems are satisfied, we can consider the Marcinkiewicz
operator.


title: Hyperplane Sections of Cylinders

abstract:
  We provide a formula to compute the volume of the intersection of a
generalized cylinder with a hyperplane. Then we prove an integral inequality
involving Bessel functions similar to Keith Ball's well-known inequality. Using
this inequality we obtain upper bounds for the section volume. For large radius
of the cylinder we determine the maximal section.


title: Ribbon-clasp surface-links and normal forms of singular surface-links

abstract:
  We introduce the notion of a ribbon-clasp surface-link, which is a
generalization of a ribbon surface-link. We generalize the notion of a normal
form on embedded surface-links to the case of immersed surface-links and prove
that any (immersed) surface-link can be described in a normal form. It is known
that an embedded surface-link is a ribbon surface-link if and only if it can be
described in a symmetric normal form. We prove that an (immersed) surface-link
is a ribbon-clasp surface-link if and only if it can be described in a
symmetric normal form. We also introduce the notion of a ribbon-clasp normal
form, which is a simpler version of a symmetric normal form.


title: Dynamics of self-propelled Janus particles in viscoelastic fluids

abstract:
  We experimentally investigate active motion of spherical Janus colloidal
particles in a viscoelastic fluid. Self-propulsion is achieved by a local
concentration gradient of a critical polymer mixture which is imposed by laser
illumination. Even in the regime where the fluid's viscosity is independent
from the deformation rate induced by the particle, we find a remarkable
increase of up to two orders of magnitude of the rotational diffusion with
increasing particle velocity, which can be phenomenologically described by an
effective rotational diffusion coefficient dependent on the Weissenberg number.
We show that this effect gives rise to a highly anisotropic response of
microswimmers in viscoelastic media to external forces depending on its
orientation.


title:
Modeling cumulative biological phenomena with Suppes-Bayes Causal
  Networks

abstract:
  Several diseases related to cell proliferation are characterized by the
accumulation of somatic DNA changes, with respect to wildtype conditions.
Cancer and HIV are two common examples of such diseases, where the mutational
load in the cancerous/viral population increases over time. In these cases,
selective pressures are often observed along with competition, cooperation and
parasitism among distinct cellular clones. Recently, we presented a
mathematical framework to model these phenomena, based on a combination of
Bayesian inference and Suppes' theory of probabilistic causation, depicted in
graphical structures dubbed Suppes-Bayes Causal Networks (SBCNs). SBCNs are
generative probabilistic graphical models that recapitulate the potential
ordering of accumulation of such DNA changes during the progression of the
disease. Such models can be inferred from data by exploiting likelihood-based
model-selection strategies with regularization. In this paper we discuss the
theoretical foundations of our approach and we investigate in depth the
influence on the model-selection task of: (i) the poset based on Suppes' theory
and (ii) different regularization strategies. Furthermore, we provide an
example of application of our framework to HIV genetic data highlighting the
valuable insights provided by the inferred.


title:
The equivariant local $\epsilon$-constant conjecture for unramified
  twists of $\mathbb{Z}_p(1)$

abstract:
  We study the equivariant local epsilon constant conjecture, denoted by
$C_{EP}^{na}(N/K,V)$, as formulated in various forms by Kato, Benois and
Berger, Fukaya and Kato and others, for certain 1-dimensional twists
$T=\mathbb{Z}_p(\chi^{nr})(1)$ of $\mathbb{Z}_p(1)$. Following ideas of recent
work of Izychev and Venjakob we prove that for $T=\mathbb{Z}_p(1)$ a conjecture
of Breuning is equivalent to $C_{EP}^{na}(N/K,V)$. As our main result we show
the validity of $C_{EP}^{na}(N/K,V)$ for certain wildly and weakly ramified
abelian extensions $N/K$. A crucial step in the proof is the construction of an
explicit representative of $R\Gamma(N,T)$.


title:
Distributed Long-Term Base Station Clustering in Cellular Networks using
  Coalition Formation

abstract:
  Interference alignment (IA) is a promising technique for interference
mitigation in multicell networks due to its ability to completely cancel the
intercell interference through linear precoding and receive filtering. In small
networks, the amount of required channel state information (CSI) is modest and
IA is therefore typically applied jointly over all base stations. In large
networks, where the channel coherence time is short in comparison to the time
needed to obtain the required CSI, base station clustering must be applied
however. We model such clustered multicell networks as a set of coalitions,
where CSI acquisition and IA precoding is performed independently within each
coalition. We develop a long-term throughput model which includes both CSI
acquisition overhead and the level of interference mitigation ability as a
function of the coalition structure. Given the throughput model, we formulate a
coalitional game where the involved base stations are the rational players.
Allowing for individual deviations by the players, we formulate a distributed
coalition formation algorithm with low complexity and low communication
overhead that leads to an individually stable coalition structure. The dynamic
clustering is performed using only long-term CSI, but we also provide a robust
short-term precoding algorithm which accounts for the intercoalition
interference when spectrum sharing is applied between coalitions. Numerical
simulations show that the distributed coalition formation is generally able to
reach long-term sum throughputs within 10 % of the global optimum.


title:
Probably Approximately Correct Greedy Maximization with Efficient Bounds
  on Information Gain for Sensor Selection

abstract:
  Submodular function maximization finds application in a variety of real-world
decision-making problems. However, most existing methods, based on greedy
maximization, assume it is computationally feasible to evaluate F, the function
being maximized. Unfortunately, in many realistic settings F is too expensive
to evaluate exactly even once. We present probably approximately correct greedy
maximization, which requires access only to cheap anytime confidence bounds on
F and uses them to prune elements. We show that, with high probability, our
method returns an approximately optimal set. We propose novel, cheap confidence
bounds for conditional entropy, which appears in many common choices of F and
for which it is difficult to find unbiased or bounded estimates. Finally,
results on a real-world dataset from a multi-camera tracking system in a
shopping mall demonstrate that our approach performs comparably to existing
methods, but at a fraction of the computational cost.


title: Quasilocal energy exchange and the null cone

abstract:
  Energy is at best defined quasilocally in general relativity. Quasilocal
energy definitions depend on the conditions one imposes on the boundary
Hamiltonian, i.e., how a finite region of spacetime is "isolated". Here, we
propose a method to define and investigate systems in terms of their matter
plus gravitational energy content. We adopt a generic construction, that
involves embedding of an arbitrary dimensional world sheet into an arbitrary
dimensional spacetime, to a 2 + 2 picture. In our case, the closed
2-dimensional spacelike surface $\mathbb{S}$, that is orthogonal to the
2-dimensional timelike world sheet $\mathbb{T}$ at every point, encloses the
system in question. The integrability conditions of $\mathbb{T}$ and
$\mathbb{S}$ correspond to three null tetrad gauge conditions once we transform
our notation to the one of the null cone observables. We interpret the
Raychaudhuri equation of $\mathbb{T}$ as a work-energy relation for systems
that are not in equilibrium with their surroundings. We achieve this by
identifying the quasilocal charge densities corresponding to rotational and
nonrotational degrees of freedom, in addition to a relative work density
associated with tidal fields. We define the corresponding quasilocal charges
that appear in our work-energy relation and which can potentially be exchanged
with the surroundings. These charges and our tetrad conditions are invariant
under type-III Lorentz transformations, i.e., the boosting of the observers in
the directions orthogonal to $\mathbb{S}$. We apply our construction to a
radiating Vaidya spacetime, a $C$-metric and the interior of a Lanczos-van
Stockum dust metric. The delicate issues related to the axially symmetric
stationary spacetimes and possible extensions to the Kerr geometry are also
discussed.


title: Non-algebraic Examples of Manifolds with the Volume Density Property

abstract:
  Some Stein manifolds (with a volume form) have a large group of
(volume-preserving) automorphisms: this is formalized by the (volume) density
property, which has remarkable consequences. Until now all known manifolds with
the volume density property are algebraic, and the tools used to establish this
property are algebraic in nature. In this note we adapt a known criterion to
the holomorphic case, and give the first known examples of non-algebraic
manifolds with the volume density property: they arise as suspensions or
pseudo-affine modifications over Stein manifolds satisfying some technical
properties. As an application we show that there are such manifolds that are
potential counterexamples to the Zariski Cancellation Problem, a variant of the
Toth-Varolin conjecture, and the problem of linearization of C*-actions on C^3.


title:
Learning Gaussian Graphical Models With Fractional Marginal
  Pseudo-likelihood

abstract:
  We propose a Bayesian approximate inference method for learning the
dependence structure of a Gaussian graphical model. Using pseudo-likelihood, we
derive an analytical expression to approximate the marginal likelihood for an
arbitrary graph structure without invoking any assumptions about
decomposability. The majority of the existing methods for learning Gaussian
graphical models are either restricted to decomposable graphs or require
specification of a tuning parameter that may have a substantial impact on
learned structures. By combining a simple sparsity inducing prior for the graph
structures with a default reference prior for the model parameters, we obtain a
fast and easily applicable scoring function that works well for even
high-dimensional data. We demonstrate the favourable performance of our
approach by large-scale comparisons against the leading methods for learning
non-decomposable Gaussian graphical models. A theoretical justification for our
method is provided by showing that it yields a consistent estimator of the
graph structure.


title: Decay $B_s\to \phi \ell^+ \ell^-$ in covariant quark model

abstract:
  Our article is devoted to the study of the rare $B_s\to \phi \ell^+\ell^-$
decay where $\ell=\mu,\tau$. We compute the relevant form factors in the
framework of the covariant quark model with infrared confinement in the full
kinematical momentum transfer region. The calculated form factors are used to
evaluate branching fractions and polarization observables in the cascade decay
$B\to \phi(\to K^+K^-)\ell^+\ell^-$. We compare the obtained results with
available experimental data and the results from other theoretical approaches.


title: Projected Estimators for Robust Semi-supervised Classification

abstract:
  For semi-supervised techniques to be applied safely in practice we at least
want methods to outperform their supervised counterparts. We study this
question for classification using the well-known quadratic surrogate loss
function. Using a projection of the supervised estimate onto a set of
constraints imposed by the unlabeled data, we find we can safely improve over
the supervised solution in terms of this quadratic loss. Unlike other
approaches to semi-supervised learning, the procedure does not rely on
assumptions that are not intrinsic to the classifier at hand. It is
theoretically demonstrated that, measured on the labeled and unlabeled training
data, this semi-supervised procedure never gives a lower quadratic loss than
the supervised alternative. To our knowledge this is the first approach that
offers such strong, albeit conservative, guarantees for improvement over the
supervised solution. The characteristics of our approach are explicated using
benchmark datasets to further understand the similarities and differences
between the quadratic loss criterion used in the theoretical results and the
classification accuracy often considered in practice.


title:
Diphoton resonances in a U(1)_{B-L} extension of the minimal
  supesymmetric standard model

abstract:
  Inspired by the 750 GeV diphoton state recently reported by ATLAS and CMS, we
propose a U(1)_{B-L} extension of the MSSM which predicts the existence of four
spin zero resonance states that are degenerate in mass in the supersymmetric
limit. Vector-like fields, a gauge singlet field, as well as the MSSM Higgsinos
are prevented from acquiring arbitrary large masses by a U(1) R-symmetry.
Indeed, these masses can be considerably lighter than the Z' gauge boson mass.
Depending on kinematics the resonance states could decay into right handed
neutrinos and sneutrinos, and/or MSSM Higgs fields and Higgsinos with total
decay widths in the multi-GeV range.


title:
Generalized Pole Inflation: Hilltop, Natural, and Chaotic Inflationary
  Attractors

abstract:
  A reformulation of inflationary model analyses appeared recently, in which
inflationary observables are determined by the structure of a pole in the
inflaton kinetic term rather than the shape of the inflaton potential. We
comprehensively study this framework with an arbitrary order of the pole taking
into account possible additional poles in the kinetic term or in the potential.
Depending on the setup, the canonical potential becomes the form of hilltop or
plateau models, variants of natural inflation, power-law inflation, or
monomial/polynomial chaotic inflation. We demonstrate attractor behaviors of
these models and compute corrections from the additional poles to the
inflationary observables.


title:
Weight Normalization: A Simple Reparameterization to Accelerate Training
  of Deep Neural Networks

abstract:
  We present weight normalization: a reparameterization of the weight vectors
in a neural network that decouples the length of those weight vectors from
their direction. By reparameterizing the weights in this way we improve the
conditioning of the optimization problem and we speed up convergence of
stochastic gradient descent. Our reparameterization is inspired by batch
normalization but does not introduce any dependencies between the examples in a
minibatch. This means that our method can also be applied successfully to
recurrent models such as LSTMs and to noise-sensitive applications such as deep
reinforcement learning or generative models, for which batch normalization is
less well suited. Although our method is much simpler, it still provides much
of the speed-up of full batch normalization. In addition, the computational
overhead of our method is lower, permitting more optimization steps to be taken
in the same amount of time. We demonstrate the usefulness of our method on
applications in supervised image recognition, generative modelling, and deep
reinforcement learning.


title:
Thermal QRPA with Skyrme interactions and supernova neutral-current
  neutrino-nucleus reactions

abstract:
  The Thermal Quasiparticle Random-Phase Approximation is combined with the
Skyrme energy density functional method (Skyrme-TQRPA) to study the response of
a hot nucleus to an external perturbation. For the sample nuclei, $^{56}$Fe and
$^{82}$Ge, the Skyrme-TQRPA is applied to analyze thermal effects on the
strength function of charge-neutral Gamow-Teller transitions which dominate
neutrino-nucleus reactions at $E_\nu \lesssim 20$~MeV. For the relevant
supernova temperatures we calculate the cross sections for inelastic neutrino
scattering. We also apply the method to examine the rate of
neutrino-antineutrino pair emission by hot nuclei. The cross sections and rates
are compared with those obtained earlier from the TQRPA calculations based on
the phenomenological Quasiparticle-Phonon Model Hamiltonian. For inelastic
neutrino scattering on $^{56}$Fe we also compare the Skyrme-TQRPA results to
those obtained earlier from a hybrid approach that combines shell-model and RPA
calculations.