title: AIC and BIC for cosmological interacting scenarios

abstract:
  In this work we study linear and non-linear cosmological interactions, which
depend on dark matter and dark energy densities in the framework of General
Relativity. By using the Akaike information criterion (AIC) and the Bayesian
information criterion (BIC) with data from SnIa (Union 2.1 and binned JLA),
H(z), BAO and CMB we compare the interacting models among themselves and
analyze whether more complex interacting models are favored by these criteria.
In this context, we find some suitable interactions that alleviate the
coincidence problem.


title: FormTracer - A Mathematica Tracing Package Using FORM

abstract:
  We present FormTracer, a high-performance, general purpose, easy-to-use
Mathematica tracing package which uses FORM. It supports arbitrary space and
spinor dimensions as well as an arbitrary number of simple compact Lie groups.
While keeping the usability of the Mathematica interface, it relies on the
efficiency of FORM. An additional performance gain is achieved by a
decomposition algorithm that avoids redundant traces in the product tensors
spaces. FormTracer supports a wide range of syntaxes which endows it with a
high flexibility. Mathematica notebooks that automatically install the package
and guide the user through performing standard traces in space-time, spinor and
gauge-group spaces are provided.


title: Non-Secant Defectivity via Osculating Projections

abstract:
  We introduce a method to produce bounds for the non secant defectivity of an
arbitrary irreducible projective variety, once we know how its osculating
spaces behave in families and when the linear projections from them are
generically finite. Then we analyze the relative dimension of osculating
projections of Grassmannians, and as an application of our techniques we prove
that asymptotically the Grassmannian $\mathbb{G}(r,n)$, parametrizing
$r$-planes in $\mathbb{P}^n$, is not $h$-defective for $h\leq
(\frac{n+1}{r+1})^{\lfloor\log_2(r)\rfloor}$. This bound improves the previous
one $h\leq \frac{n-r}{3}+1$, due to H. Abo, G. Ottaviani and C. Peterson, for
any $r\geq 4$.


title: Word Embeddings for the Construction Domain

abstract:
  We introduce word vectors for the construction domain. Our vectors were
obtained by running word2vec on an 11M-word corpus that we created from scratch
by leveraging freely-accessible online sources of construction-related text. We
first explore the embedding space and show that our vectors capture meaningful
construction-specific concepts. We then evaluate the performance of our vectors
against that of ones trained on a 100B-word corpus (Google News) within the
framework of an injury report classification task. Without any parameter
tuning, our embeddings give competitive results, and outperform the Google News
vectors in many cases. Using a keyword-based compression of the reports also
leads to a significant speed-up with only a limited loss in performance. We
release our corpus and the data set we created for the classification task as
publicly available, in the hope that they will be used by future studies for
benchmarking and building on our work.


title: Real-time Online Action Detection Forests using Spatio-temporal Contexts

abstract:
  Online action detection (OAD) is challenging since 1) robust yet
computationally expensive features cannot be straightforwardly used due to the
real-time processing requirements and 2) the localization and classification of
actions have to be performed even before they are fully observed. We propose a
new random forest (RF)-based online action detection framework that addresses
these challenges. Our algorithm uses computationally efficient skeletal joint
features. High accuracy is achieved by using robust convolutional neural
network (CNN)-based features which are extracted from the raw RGBD images, plus
the temporal relationships between the current frame of interest, and the past
and future frames. While these high-quality features are not available in
real-time testing scenario, we demonstrate that they can be effectively
exploited in training RF classifiers: We use these spatio-temporal contexts to
craft RF's new split functions improving RFs' leaf node statistics. Experiments
with challenging MSRAction3D, G3D, and OAD datasets demonstrate that our
algorithm significantly improves the accuracy over the state-of-the-art online
action detection algorithms while achieving the real-time efficiency of
existing skeleton-based RF classifiers.


title:
Another baryon miracle? Testing solutions to the "missing dwarfs"
  problem

abstract:
  The dearth of dwarf galaxies in the local universe is hard to reconcile with
the large number of low mass haloes expected within the concordance
$\Lambda$CDM paradigm. In this paper we perform a systematic evaluation of the
uncertainties affecting the measurement of DM halo abundance using galaxy
kinematics. Using a large sample of dwarf galaxies with spatially resolved
kinematic data we derive a correction to obtain the observed abundance of
galaxies as a function of their halo maximum circular velocity from the
line-of-sight velocity function in the Local Volume. This estimate provides a
direct means of comparing the predictions of theoretical models and simulations
(including nonstandard cosmologies and novel galaxy formation physics) to the
observational constraints. The new "galactic $V_{max}$" function is steeper
than the line-of-sight velocity function but still shallower than the
theoretical CDM expectation, showing that some unaccounted physical process is
necessary to reduce the abundance of galaxies and/or drastically modify their
density profiles compared to CDM haloes. Using this new galactic $V_{max}$
function, we investigate the viability of baryonic solutions such as
feedback-powered outflows and photoevaporation of gas from an ionising
radiation background. At the 3-$\sigma$ confidence level neither energetic
feedback nor photoevaporation are effective enough to reconcile the
disagreement. In the case of maximum baryonic effects, the theoretical estimate
still deviates significantly from the observations for $V_{max} < 60$ km/s. CDM
predicts at least 1.8 times more galaxies with $V_{max} = 50$ km/s and 2.5
times more than observed at $30$ km/s. Recent hydrodynamic simulations seem to
resolve the discrepancy but disagree with the properties of observed galaxies
with resolved kinematics. (abridged)


title: Differential Embedding Problems over Complex Function Fields

abstract:
  We introduce the notion of differential torsors, which allows the adaptation
of constructions from algebraic geometry to differential Galois theory. Using
these differential torsors, we set up a general framework for applying patching
techniques in differential Galois theory over fields of characteristic zero. We
show that patching holds over function fields over the complex numbers. As the
main application, we prove the solvability of all differential embedding
problems over complex function fields, thereby providing new insight on the
structure of the absolute differential Galois group, i.e., the fundamental
group of the underlying Tannakian category.


title:
Interplay of orbital effects and nanoscale strain in topological
  crystalline insulators

abstract:
  Orbital degrees of freedom can have pronounced effects on the fundamental
properties of electrons in solids. In addition to influencing bandwidths, gaps,
correlation strength and dispersion, orbital effects have also been implicated
in generating novel electronic and structural phases, such as Jahn-Teller
effect and colossal magnetoresistance. In this work, we show for the first time
how the orbital nature of bands can result in non-trivial effects of strain on
the band structure. We use scanning tunneling microscopy and quasiparticle
interference imaging to study the effects of strain on the electronic structure
of a heteroepitaxial thin film of a topological crystalline insulator, SnTe. We
find a surprising effect where strain applied in one direction affects the band
structure in the perpendicular direction. Our theoretical calculations indicate
that this effect directly arises from the orbital nature of the conduction and
valance bands. Our results imply that a microscopic model capturing strain
effects on the band structure must include a consideration of the orbital
nature of the bands.


title:
Explicit solution for Stefan problem with latent heat depending on the
  position and a convective boundary condition at the fixed face using Kummer
  functions

abstract:
  An explicit solution of a similarity type is obtained for a one-phase Stefan
problem in a semi-infinite material using Kummer functions. Motivated by [D.A.
Tarzia, Relationship between Neumann solutions for two phase
Lam\'e-Clapeyron-Stefan problems with convective and temperature boundary
conditions, Thermal Sci.(2016) DOI 10.2298/TSCI 140607003T, In press], and [Y.
Zhou, L.J. Xia, Exact solution for Stefan problem with general power-type
latent heat using Kummer function, Int. J. Heat Mass Transfer, 84 (2015)
114-118], we consider a phase-change problem with a latent heat defined as a
power function of the position with a non-negative real exponent and a
convective boundary condition at the fixed face $x=0$. Existence and uniqueness
of the solution is proved. Relationship between this problem and the problems
already solved by Zhou and Xia with temperature and flux boundary condition is
analysed. Furthermore it is studied the limit behaviour of the solution when
the coefficient which characterizes the heat transfer at the fixed boundary
tends to infinity. Numerical computation of the solution is done over certain
examples, with a view to comparing this results with those obtained by general
algorithms that solve Stefan problems.


title: Radiative transfer on decretion discs of Be binaries

abstract:
  In this work we explore the effect of binarity in the decretion disc of Be
stars, in order to explain their variability. To this aim, we performed
smoothed particle hydrodynamics (SPH) simulations on Be binary systems,
following the matter ejected isotropically from the equator of the Be star
towards the base of an isothermal decretion disc. We let the system evolve for
time long enough to be considered at steady state, and focus on the effect of
viscosity for coplanar prograde binary orbits. The disc structure is found to
be locked to the orbital phase, exhibiting also a dependence on the azimuthal
angle.
  Additionally, we present the first results from detailed non-local
thermodynamic equilibrium (non-LTE) radiative transfer calculations of the disc
structure computed with the SPH code. This is achieved by the use of the
three-dimensional (3D) Monte Carlo code HDUST, which can produce predictions
with respect to a series of observables.


title: Cell division and death inhibit glassy behaviour of confluent tissues

abstract:
  We investigate the effects of cell division and apopotosis on collective
dynamics in two-dimensional epithelial tissues. Our model includes three key
ingredients observed across many epithelia, namely cell-cell adhesion, cell
death and a cell division process that depends on the surrounding environment.
We show a rich non-equilibrium phase diagram depending on the ratio of cell
death to cell division and on the adhesion strength. For large apopotosis
rates, cells die out and the tissue disintegrates. As the death rate decreases,
however, we show, consecutively, the existence of a gas-like phase, a gel-like
phase, and a dense confluent (tissue) phase. Most striking is the observation
that the tissue is self-melting through its own internal activity, ruling out
the existence of any glassy phase.


title:
Autonomous frequency stabilization of two extended cavity diode lasers
  at the potassium wavelength on a sounding rocket

abstract:
  We have developed, assembled, and flight-proven a stable, compact, and
autonomous extended cavity diode laser (ECDL) system designed for atomic
physics experiments in space. To that end, two micro-integrated ECDLs at 766.7
nm were frequency stabilized during a sounding rocket flight by means of
frequency modulation spectroscopy (FMS) of 39^K and offset locking techniques
based on the beat note of the two ECDLs. The frequency stabilization as well as
additional hard- and software to test hot redundancy mechanisms were
implemented as part of a state-machine, which controlled the experiment
completely autonomously throughout the entire flight mission.


title: Electronic transport and scattering times in tungsten-decorated graphene

abstract:
  The electronic transport properties of monolayer graphene have been studied
before and after the deposition of a dilute coating of tungsten adatoms on the
surface. For coverages up to 2.5\% of a monolayer, we find tungsten adatoms
simultaneously donate electrons to graphene and reduce the carrier mobility,
impacting the zero- and finite-field transport properties. Two independent
transport analyses suggest the adatoms lie nearly 1 nm above the surface. The
presence of adatoms is also seen to impact the low field magnetoresistance,
altering the signatures of weak localization.


title: Conditioning a Brownian loop-soup cluster on a portion of its boundary

abstract:
  We show that if one conditions a cluster in a Brownian loop-soup $L$ (of any
intensity) in a two-dimensional domain by a portion $l$ of its outer boundary,
then in the remaining domain, the union of all the loops of $L$ that touch $l$
satisfies the conformal restriction property while the other loops in $L$ form
an independent loop-soup. This result holds when one discovers $l$ in a natural
Markovian way, such as in the exploration procedures that have been defined in
order to actually construct the Conformal Loop Ensembles as outer boundaries of
loop-soup clusters. This result implies among other things that a phase
transition occurs at c = 14/15 for the connectedness of the loops that touch
$l$.
  Our results can be viewed as an extension of some of the results in our
earlier paper in the following two directions: There, a loop-soup cluster was
conditioned on its entire outer boundary while we discover here only part of
this boundary. And, while it was explained there that the strong decomposition
using a Poisson point process of excursions that we derived there should be
specific to the case of the critical loop-soup, we show here that in the
subcritical cases, a weaker property involving the conformal restriction
property nevertheless holds.


title: Design Overview of the DM Radio Pathfinder Experiment

abstract:
  We introduce the DM Radio, a dual search for axion and hidden photon dark
matter using a tunable superconducting lumped-element resonator. We discuss the
prototype DM Radio Pathfinder experiment, which will probe hidden photons in
the 500 peV (100 kHz)-50 neV (10 MHz) mass range. We detail the design of the
various components: the LC resonant detector, the resonant frequency tuning
procedure, the differential SQUID readout circuit, the shielding, and the
cryogenic mounting structure. We present the current status of the pathfinder
experiment and illustrate its potential science reach in the context of the
larger experimental program.


title:
Fault Detection in IEEE 14-Bus Power System with DG Penetration Using
  Wavelet Transform

abstract:
  Wavelet transform is proposed in this paper for detection of islanding and
fault disturbances distributed generation (DG) based power system. An IEEE
14-bus system with DG penetration is considered for the detection of
disturbances under different operating conditions. The power system is a hybrid
combination of photovoltaic, and wind energy system connected to different
buses with different level of penetration. The voltage signal is retrieved at
the point of common coupling (PCC) and processed through wavelet transform to
detect the disturbances. Further, energy and standard deviation (STD) as
performance indices are evaluated and compared with a suitable threshold in
order to analyze a disturbance condition. Again, a comparative analysis between
the existing and proposed detection is studied to prove the better performance
of wavelet transform.


title: Collisional Model of Energy Dissipation in 3D Granular Impact

abstract:
  We study the dynamic process occurring when a granular assembly is displaced
by a solid impactor. The momentum transfer from the impactor to the target is
shown to occur through sporadic, normal collisions of high force carrying
grains at the intruder surface. We therefore describe the stopping force of the
impact through a collisional based model. To verify the model in impact
experiments, we determine the forces acting on an intruder decelerating through
a dense granular medium using high-speed imaging of its trajectory. By varying
the intruder shape and granular target, intruder-grain interactions are
inferred from the consequent path. As a result, we connect the drag to the
effect of intruder shape and grain density based on a proposed collisional
model.


title:
Beyond Quantum Theory: A Realist Psychobiological Interpretation of
  Physical Reality

abstract:
  Stapp and others have proposed that reality involves a fundamental life
process, or creative process. It is shown how this process description may be
unified with the description that derives from quantum physics. The methods of
the quantum physicist and of the biological sciences are seen to be two
alternative approaches to the understanding of nature, involving two distinct
modes of description which can usefully supplement each other, and neither on
its own contains the full story. The unified view explains the major features
of quantum mechanics and suggests that biological systems may function more
effectively than would be expected on the basis of quantum mechanics alone.


title: Orbifolds and cosets of minimal $\mathcal{W}$-algebras

abstract:
  Let $\mathfrak{g}$ be a simple, finite-dimensional Lie (super)algebra
equipped with an embedding of $\mathfrak{s} \mathfrak{l}_2$ inducing the
minimal gradation on $\mathfrak{g}$. The corresponding minimal
$\mathcal{W}$-algebra $\mathcal{W}^k(\mathfrak{g}, e_{-\theta})$ introduced by
Kac and Wakimoto has strong generators in weights $1,2,3/2$, and all operator
product expansions are known explicitly. The weight one subspace generates an
affine vertex (super)algebra $V^{k'}(\mathfrak{g}^{\natural})$ where
$\mathfrak{g}^{\natural} \subset \mathfrak{g}$ denotes the centralizer of
$\mathfrak{s} \mathfrak{l}_2$. Therefore $\mathcal{W}^k(\mathfrak{g},
e_{-\theta})$ has an action of a connected Lie group $G^{\natural}_0$ with Lie
algebra $\mathfrak{g}^{\natural}_0$, where $\mathfrak{g}^{\natural}_0$ denotes
the even part of $\mathfrak{g}^{\natural}$. We show that for any reductive
subgroup $G \subset G^{\natural}_0$, and for any reductive Lie algebra
$\mathfrak{g}' \subset \mathfrak{g}^{\natural}$, the orbifold $\mathcal{O}^k =
\mathcal{W}^k(\mathfrak{g}, e_{-\theta})^{G}$ and the coset $\mathcal{C}^k =
\text{Com}(V(\mathfrak{g}'),\mathcal{W}^k(\mathfrak{g}, e_{-\theta}))$ are
strongly finitely generated for generic values of $k$. Here $V(\mathfrak{g}')$
denotes the affine vertex algebra associated to $\mathfrak{g}'$. We find
explicit minimal strong generating sets for $\mathcal{C}^k$ when $\mathfrak{g}'
= \mathfrak{g}^{\natural}$ and $\mathfrak{g}$ is either $\mathfrak{s}
\mathfrak{l}_n$, $\mathfrak{s}\mathfrak{p}_{2n}$,
$\mathfrak{s}\mathfrak{l}(2|n)$ for $n\neq 2$,
$\mathfrak{p}\mathfrak{s}\mathfrak{l}(2|2)$, or
$\mathfrak{o}\mathfrak{s}\mathfrak{p}(1|4)$. Finally, we conjecture some
surprising coincidences among families of cosets $\mathcal{C}_k$ which are the
simple quotients of $\mathcal{C}^k$, and we prove several cases of our
conjecture.


title:
A nanoCryotron comparator can connect single-flux quantum circuits to
  conventional electronics

abstract:
  Integration with conventional electronics offers a straightforward and
economical approach to upgrading existing superconducting technologies, such as
scaling up superconducting detectors into large arrays and combining single
flux quantum (SFQ) digital circuits with semiconductor logic and memories.
However, direct output signals from superconducting devices (e.g., Josephson
junctions) are usually not compatible with the input requirements of
conventional devices (e.g., transistors). Here, we demonstrate the use of a
single three-terminal superconducting-nanowire device, called the nanocryotron
(nTron), as a digital comparator to combine SFQ circuits with mature
semiconductor circuits such as complementary metal oxide semiconductor (CMOS)
circuits. Since SFQ circuits can digitize output signals from general
superconducting devices and CMOS circuits can interface existing
CMOS-compatible electronics, our results demonstrate the feasibility of a
general architecture that uses an nTron as an interface to realize a
super-hybrid system consisting of superconducting detectors, superconducting
quantum electronics, CMOS logic and memories, and other conventional
electronics.


title: The origin of exciton mass in a frustrated Mott insulator Na$_2$IrO$_3$

abstract:
  We use a three-pulse ultrafast optical spectroscopy to study the relaxation
processes in a frustrated Mott insulator Na$_2$IrO$_3$. By being able to
independently produce the out-of-equilibrium bound states (excitons) of
doublons and holons with the first pulse and suppress the underlying
antiferromagnetic order with the second one, we were able to elucidate the
relaxation mechanism of quasiparticles in this system. By observing the
difference in the exciton dynamics in the magnetically ordered and disordered
phases we found that the mass of this quasiparticle is mostly determined by its
interaction with the surrounding spins.


title:
Phonon-Mediated Quasiparticle Poisoning of Superconducting Microwave
  Resonators

abstract:
  Nonequilibrium quasiparticles represent a significant source of decoherence
in superconducting quantum circuits. Here we investigate the mechanism of
quasiparticle poisoning in devices subjected to local quasiparticle injection.
We find that quasiparticle poisoning is dominated by the propagation of
pair-breaking phonons across the chip. We characterize the energy dependence of
the timescale for quasiparticle poisoning. Finally, we observe that
incorporation of extensive normal metal quasiparticle traps leads to a more
than order of magnitude reduction in quasiparticle loss for a given injected
quasiparticle power.


title:
The role of viscosity contrast on plume structure in laboratory modeling
  of mantle convection

abstract:
  We have conducted laboratory experiments to model important aspects of plumes
in mantle convection. We focus on the role of the viscosity ratio U (between
the ambient fluid and the plume fluid) in determining the plume structure and
dynamics. In our experiments, we are able to capture geophysical convection
regimes relevant to mantle convection both for hot spots (when U > 1) and
plate-subduction (when U < 1) regimes. The planar laser induced fluorescence
(PLIF) technique is used for flow visualization and characterizing the plume
structures. The convection is driven by compositional buoyancy generated by the
perfusion of lighter fluid across a permeable mesh and the viscosity ratio U is
systematically varied over a range from 1/300 to 2500. The planform, near the
bottom boundary for U=1, exhibits a well-known dendritic line plume structure.
As the value of U is increased, a progressive morphological transition is
observed from the dendritic-plume structure to discrete spherical plumes,
accompanied with thickening of the plumes and an increase in the plume spacing.
In the vertical section, mushroom-shaped plume heads at U=1 change into
intermittent spherical-blob shaped plumes at high U, resembling mantle plume
hot spots in mantle convection. In contrast, for low values of U (~1/300), the
regime corresponds to subduction of plates in the mantle. In this regime, we
observe for the first time that plumes arise from a thick boundary with
cellular structure and develop into sheet-plumes. We use experimental data to
quantify these morphological changes and mixing dynamics of the plumes at
different regimes of U. We also compare our observations on plume spacing with
various models reported in the literature by varying the viscosity ratio and
the buoyancy flux.

categories: physics.flu-dyn nlin.AO nlin.PS physics.geo-ph


title: Eigenvalue spectra of large correlated random matrices

abstract:
  Using the diagrammatic method, we derive a set of self-consistent equations
that describe eigenvalue distributions of large correlated asymmetric random
matrices. The matrix elements can have different variances and be correlated
with each other. The analytical results are confirmed by numerical simulations.
The results have implications for the dynamics of neural and other biological
networks where plasticity induces correlations in the connection strengths
within the network. We find that the presence of correlations can have a major
impact on network stability.


title:
Measurement of the Cold Dark Matter-Neutrino Dipole in the TianNu
  Simulation

abstract:
  Measurements of neutrino mass in cosmological observations rely on two point
statistics that are hindered by significant degeneracies with the optical depth
and galaxy bias. The relative velocity effect between cold dark matter and
neutrinos induces a large scale dipole into the matter density field and may be
able to provide orthogonal constraints to standard techniques. We numerically
investigate this dipole in the TianNu Simulation, which contains cold dark
matter and 50 meV neutrinos. We first compute the dipole using a new linear
response technique where we treat the displacement caused by the relative
velocity as a phase in Fourier space and then integrate the matter power
spectrum over redshift. Then, we compute the dipole numerically in real space
using the simulation density and velocity fields. We find excellent agreement
between the linear response and N-body methods. Utilizing the dipole as an
observational tool will require two tracers of the matter distribution that are
differently biased with respect to the neutrino density.


title: Absence of bilinear condensate in three-dimensional QED

abstract:
  There are plausibility arguments that QED in three dimensions has a critical
number of flavors of massless two-component fermions, below which scale
invariance is broken by the presence of bilinear condensate. We present
numerical evidences from our lattice simulations using dynamical overlap as
well as Wilson-Dirac fermions for the absence of bilinear condensate for any
even number of flavors of two-component fermions. Instead, we find evidences
for the scale-invariant nature of three-dimensional QED.


title: A nonpolynomially convex isotropic two-torus with no attached discs

abstract:
  We show --- with the means of a real-analytic example in $\mathbb{C}^3$ ---
that Gromov's theorem on the presence of attached holomorphic discs for compact
Lagrangian manifolds is not true in the isotropic (subcritical) case, even in
the absence of an obvious obstruction, i.e, polynomial convexity.


title: Testing Lorentz and CPT Symmetries in Penning Traps

abstract:
  A modified Dirac equation with general Lorentz- and CPT-violating operators
in the electromagnetic field is studied. Constraints on and possible
sensitivities to Lorentz-violating coefficients in the nonminimal sector up to
mass-dimension six can be obtained by analyzing Penning-trap results involving
anomaly frequencies.


title:
Increased methane emissions from deep osmotic and buoyant convection
  beneath submarine seeps as climate warms

abstract:
  High speeds have been measured at seep and mud-volcano sites expelling
methane-rich fluids from the seabed. Thermal or solute-driven convection alone
cannot explain such high velocities in low-permeability sediments. Here, we
demonstrate that in addition to buoyancy, osmotic effects generated by the
adsorption of methane onto the sediments can create large overpressures,
capable of recirculating seawater from the seafloor to depth in the sediment
layer, then expelling it upwards at rates of up to a few hundreds of metres per
year. In the presence of global warming, such deep recirculation of seawater
can accelerate the melting of methane hydrates at depth from timescales of
millennia to just decades, and can drastically increase the rate of release of
methane into the hydrosphere and perhaps the atmosphere.


title:
South Korean degenerative spondylolisthesis patients had surgical
  treatment at earlier age than Japanese, American, and European patients: a
  published literature observation

abstract:
  Physical therapy is the first line of treatment for adults with symptoms from
degenerative spondylolisthesis. Surgical management is offered when
nonoperative options have not adequately relieved symptoms. We performed PubMed
literature search with the word 'spondylolisthesis', and updated till September
18, 2016. We selected original research data involving surgical treatment of
degenerative spondylolisthesis, and in total there were n articles, including
data reported from Japan (n=37 series), South Korea (n=11 series), mainland
China (n=5 series), and ROC (Taiwan, n=3 series), America (n=20 series), Europe
(n=23 series). The mean age of each study were extracted and used a single
entry. We tried our best to filter out double/multiple reported data. Our
results showed the median age of degenerative spondylolisthesis patients
underwent surgical treatment was 66 years in Japan, 60 years in South Korea, 59
years in mainland China, 59 years in ROC (Taiwan), 65 years in USA, and 66
years in Europe. This study indicates Japan and South Korea may have different
surgical practice pattern. It will be of interested to investigate whether more
proportion of degenerative spondylolisthesis patients have been treated
surgically in South Korea than in Japan. The cost-effectiveness of different
approaches may warrant further analysis by professional spine surgeons.


title: Insulating nanomagnets driven by spin torque

abstract:
  Magnetic insulators, such as yttrium iron garnet (Y$_3$Fe$_5$O$_{12}$), are
ideal materials for ultra-low power spintronics applications due to their low
energy dissipation and efficient spin current generation and transmission.
Recently, it has been realized that spin dynamics can be driven very
effectively in micrometer-sized Y$_3$Fe$_5$O$_{12}$/Pt heterostructures by
spin-Hall effects. We demonstrate here the excitation and detection of spin
dynamics in Y$_3$Fe$_5$O$_{12}$/Pt nanowires by spin-torque ferromagnetic
resonance. The nanowires defined via electron-beam lithography are fabricated
by conventional room temperature sputtering deposition on Gd$_3$Ga$_5$O$_{12 }$
substrates and lift-off. We observe field-like and anti-damping-like torques
acting on the magnetization precession, which are due to simultaneous
excitation by Oersted fields and spin-Hall torques. The Y$_3$Fe$_5$O$_{12}$/Pt
nanowires are thoroughly examined over a wide frequency and power range. We
observe a large change in the resonance field at high microwave powers, which
is attributed to a decreasing effective magnetization due to microwave
absorption. These heating effects are much more pronounced in the investigated
nanostructures than in comparable micron-sized samples. By comparing different
nanowire widths, the importance of geometrical confinements for magnetization
dynamics becomes evident: quantized spin-wave modes across the width of the
wires are observed in the spectra. Our results are the first stepping stones
toward the realization of integrated magnonic logic devices based on
insulators, where nanomagnets play an essential role.


title:
A matrix variation on Ramus's identity for lacunary sums of binomial
  coefficients

abstract:
  We study the well-known lacunary sums of binomial coefficients considered,
most notably, by Christian Ramus, and their connection to a special kind of
harmonic number associated with the first case of Fermat's Last Theorem. For
one case of Ramus's famous identity we obtain a variation in which some of the
parameters are replaced by square matrices of arbitrary dimension.


title: Inflection-point Higgs Inflation

abstract:
  Inflection-point inflation is an interesting possibility to realize a
successful slow-roll inflation when inflation is driven by a single scalar
field with its initial value below the Planck mass ($\phi_I \lesssim M_{Pl}$).
In order for a renormalization group (RG) improved effective $\lambda \phi^4$
potential to develop an inflection-point, the quartic coupling $\lambda(\phi)$
must exhibit a minimum with an almost vanishing value in its RG evolution,
namely $\lambda(\phi_I) \simeq 0$ and $\beta_{\lambda}(\phi_I) \simeq 0$, where
$\beta_{\lambda}$ is the beta-function of the quartic coupling. As an example,
we consider the minimal gauged $B-L$ extended Standard Model at the TeV scale,
where we identify the $B-L$ Higgs field as the inflaton field. For a successful
inflection-point inflation, which is consistent with the current cosmological
observations, the mass ratios among the $Z^{\prime}$ gauge boson, the
right-handed neutrinos and the $B-L$ Higgs boson are fixed. Our scenario can be
tested in the future collider experiments such as the High-Luminosity LHC and
the SHiP experiments. In addition, the inflection-point inflation provides a
unique prediction for the running of the spectral index $\alpha \simeq - 2.7
\times 10^{-3}\left(\frac{60}{N}\right)^2$ ($N$ is the $e$-folding number),
which can be tested in the near future.


title:
Estimating Derivatives of Function-Valued Parameters in a Class of
  Moment Condition Models

abstract:
  We develop a general approach to estimating the derivative of a
function-valued parameter $\theta_o(u)$ that is identified for every value of
$u$ as the solution to a moment condition. This setup in particular covers many
interesting models for conditional distributions, such as quantile regression
or distribution regression. Exploiting that $\theta_o(u)$ solves a moment
condition, we obtain an explicit expression for its derivative from the
Implicit Function Theorem, and estimate the components of this expression by
suitable sample analogues, which requires the use of (local linear) smoothing.
Our estimator can then be used for a variety of purposes, including the
estimation of conditional density functions, quantile partial effects, and
structural auction models in economics.


title: Jet structure modifications in heavy-ion collisions with JEWEL

abstract:
  Key features of jet-medium interactions in heavy-ion collisions are
modifications to the jet structure. Recent results from experiments at the LHC
and RHIC have motivated several theoretical calculations and monte carlo models
towards predicting these observables simultaneously. In this report, the recoil
picture in \textsc{Jewel} is summarized and two independent procedures through
which background subtraction can be performed in \textsc{Jewel} are introduced.
Information of the medium recoil in \textsc{Jewel} significantly improves its
description of several jet shape measurements.


title: Establishing the origin of CMB B-mode polarization

abstract:
  Primordial gravitational waves leave a characteristic imprint on the cosmic
microwave background (CMB) in the form of $B$-mode polarization. Photons are
also deflected by large scale gravitational waves which intervene between the
source screen and our telescopes, resulting in curl-type gravitational lensing.
Gravitational waves present at the epoch of reionization contribute to both
effects, thereby leading to a non-vanishing cross-correlation between $B$-mode
polarization and curl lensing of the CMB. Observing such a cross correlation
would be very strong evidence that an observation of $B$-mode polarization was
due to the presence of large scale gravitational waves, as opposed to
astrophysical foregrounds or experimental systematic effects. We study the
cross-correlation across a wide range of source redshifts and show that a
post-SKA experiment aimed to map out the 21-cm sky between $15 \leq z \leq 30$
could rule out non-zero cross-correlation at high significance for $r \geq
0.01$.


title: The Non-Existent Complex 6-Sphere

abstract:
  The possible existence of a complex structure on the 6-sphere has been a
famous unsolved problem for over 60 years. In that time many "solutions" have
been put forward, in both directions. Mistakes have always been found. In this
paper I present a short proof of the non-existence, based on ideas developed,
but not fully exploited, over 50 years ago. The only change in v2. is in
section 3, where the notation has been clarified.


title: Excited-State Wigner Crystals in One Dimension

abstract:
  Wigner crystals (WC) are electronic phases peculiar to low-density systems,
particularly in the uniform electron gas. Since its introduction in the early
twentieth century, this model has remained essential to many aspects of
electronic structure theory and condensed-matter physics. Although the
(lowest-energy) ground-state WC (GSWC) has been thoroughly studied, the
properties of excited-state WCs (ESWCs) are basically unknown. To bridge this
gap, we present a well-defined procedure to obtain an entire family of ESWCs in
a one-dimensional electron gas using a symmetry-broken mean-field approach.
While the GSWC is a commensurate crystal (i.e.~the number of density maxima
equals the number of electrons), these ESWCs are incommensurate crystals
exhibiting more or less maxima. Interestingly, they are lower in energy than
the (uniform) Fermi fluid state. For some of these ESWCs we have found
asymmetrical band gaps, which would lead to anisotropic conductivity. These
properties are associated to unusual characteristics in their electronic
structure.

categories: cond-mat.mes-hall cond-mat.other cond-mat.quant-gas cond-mat.str-el physics.chem-ph


title: Impact of finite density on spectroscopic parameters of decuplet baryons

abstract:
  The decuplet baryons, $\Delta$, $\Sigma^{*}$, $\Xi^{*}$ and $\Omega^{-}$, are
studied in nuclear matter by using the in-medium QCD sum rules. By fixing the
three momentum of the particles under consideration at the rest frame of the
medium, the negative energy contributions are removed. It is obtained that the
parameters of the $\Delta$ baryon are more affected by the medium against the
$\Omega^{-}$ state, containing three strange quarks, whose mass and residue do
not affected by the medium, considerably. We also find the vector and scalar
self energies of these baryons in nuclear matter. By the recent progresses at
$\bar{P}$ANDA experiment at FAIR and NICA facility it may be possible to study
the in-medium properties of such states even the multi-strange $\Xi^{*}$ and
$\Omega^{-}$ systems in near future.


title: Discriminative Gaifman Models

abstract:
  We present discriminative Gaifman models, a novel family of relational
machine learning models. Gaifman models learn feature representations bottom up
from representations of locally connected and bounded-size regions of knowledge
bases (KBs). Considering local and bounded-size neighborhoods of knowledge
bases renders logical inference and learning tractable, mitigates the problem
of overfitting, and facilitates weight sharing. Gaifman models sample
neighborhoods of knowledge bases so as to make the learned relational models
more robust to missing objects and relations which is a common situation in
open-world KBs. We present the core ideas of Gaifman models and apply them to
large-scale relational learning problems. We also discuss the ways in which
Gaifman models relate to some existing relational machine learning approaches.


title:
Uniform convergent scheme for strongly anisotropic diffusion equations
  with closed field lines

abstract:
  In magnetized plasma, the magnetic field confines particles around field
lines. The ratio between the intensity of the parallel and perpendicular
viscosity or heat conduction may reach the order of $10^{12}$. When the
magnetic fields have closed field lines and form a "magnetic island", the
convergence order of most known schemes depends on the anisotropy strength. In
this paper, by integration of the original differential equation along each
closed field line, we introduce a simple but very efficient asymptotic
preserving reformulation, which yields uniform convergence with respect to the
anisotropy strength. Only slight modification to the original code is required
and neither change of coordinates nor mesh adaptation is needed. Numerical
examples demonstrating the performance of the new scheme are presented.


title: The Mutando of Insanity

abstract:
  Puzzles based on coloured cubes and other coloured geometrical figures have a
long history in the recreational mathematical literature. One of the most
commercially famous of these puzzles is the Instant Insanity that consists of
four cubes. Their faces are coloured with four different colours in such a way
that each colour is present in each one of the four cubes. To solve the puzzle,
one needs to stack the cubes in a tower in such a way that each one of the
colours appears exactly once in the four long faces of the tower. The main
purpose of this paper is to study the combinatorial richness of a mathematical
model of this puzzle by analysing all possible ways of colouring the cubes to
form a puzzle analogous to the Instant Insanity. We have done this analysis for
$n$ cubes and $n$ colours for $n=4, 5, 6$. This combinatorial analysis allowed
us to design the Mutando of Insanity, a puzzle that we presented at Gathering
for Gardner 12 (G4G12).


title:
A Projective Simulation Scheme for Partially-Observable Multi-Agent
  Systems

abstract:
  We introduce a kind of partial observability to the projective simulation
(PS) learning method. It is done by adding a belief projection operator and an
observability parameter to the original framework of the efficiency of the PS
model. I provide theoretical formulations, network representations, and
situated scenarios derived from the invasion toy problem as a starting point
for some multi-agent PS models.


title:
Precision determination of the small-$x$ gluon from charm production at
  LHCb

abstract:
  The small-$x$ gluon in global fits of parton distributions is affected by
large uncertainties from the lack of direct experimental constraints. In this
work we provide a precision determination of the small-$x$ gluon from the
exploitation of forward charm production data provided by LHCb for three
different centre-of-mass (CoM) energies: 5~TeV, 7~TeV and 13~TeV. The LHCb
measurements are included in the PDF fit by means of normalized distributions
and cross-section ratios between data taken at different CoM values, $R_{13/7}$
and $R_{13/5}$. We demonstrate that forward charm production leads to a
reduction of the PDF uncertainties of the gluon down to $x\simeq 10^{-6}$ by up
to an order of magnitude, with implications for high-energy colliders, cosmic
ray physics and neutrino astronomy.


title:
Differences in the rotational properties of multiple stellar populations
  in M 13: a faster rotation for the "extreme" chemical subpopulation

abstract:
  We use radial velocities from spectra of giants obtained with the WIYN
telescope, coupled with existing chemical abundance measurements of Na and O
for the same stars, to probe the presence of kinematic differences among the
multiple populations of the globular cluster (GC) M13. To characterise the
kinematics of various chemical subsamples, we introduce a method using Bayesian
inference along with an MCMC algorithm to fit a six-parameter kinematic model
(including rotation) to these subsamples. We find that the so-called "extreme"
population (Na-enhanced and extremely O-depleted) exhibits faster rotation
around the centre of the cluster than the other cluster stars, in particular
when compared to the dominant "intermediate" population (moderately Na-enhanced
and O-depleted). The most likely difference between the rotational amplitude of
this extreme population and that of the intermediate population is found to be
$\sim$4 km s$^{-1}$, with a 98.4% probability that the rotational amplitude of
the extreme population is larger than that of the intermediate population. We
argue that the observed difference in rotational amplitudes, obtained when
splitting subsamples according to their chemistry, is not a product of the
long-term dynamical evolution of the cluster, but more likely a surviving
feature imprinted early in the formation history of this GC and its multiple
populations. We also find an agreement (within uncertainties) in the inferred
position angle of the rotation axis of the different subpopulations considered.
We discuss the constraints that these results may place on various formation
scenarios.


title: Planetary Torque in 3D Isentropic Disks

abstract:
  Planet migration is inherently a three-dimensional (3D) problem, because
Earth-size planetary cores are deeply embedded in protoplanetary disks.
Simulations of these 3D disks remain challenging due to the steep requirement
in resolution. Using two different hydrodynamics code, FARGO3D and PEnGUIn, we
simulate disk-planet interaction for a 1 to 5 Earth-mass planet embedded in an
isentropic disk. We measure the torque on the planet and ensure that the
measurements are converged both in resolution and between the two codes. We
find that the torque is independent of the smoothing length of the planet's
potential ($r_{\rm s}$), and that it has a weak dependence on the adiabatic
index of the gaseous disk ($\gamma$). The torque values correspond to an inward
migration rate qualitatively similar to previous linear calculations. We
perform additional simulations with explicit radiative transfer using FARGOCA,
and again find agreement between 3D simulations and existing torque formulae.
We also present the flow pattern around the planets, and show that active flow
is present within the planet's Hill sphere, and meridional vortices are shed
downstream. The vertical flow speed near the planet is faster for a smaller
$r_{\rm s}$ or $\gamma$, up to supersonic speeds for the smallest $r_{\rm s}$
and $\gamma$ in our study.


title: FRICAT: A FIRST catalog of FRI radio galaxies

abstract:
  We built a catalog of 219 FRI radio galaxies (FRIs), called FRICAT, selected
from a published sample and obtained by combining observations from the NVSS,
FIRST, and SDSS surveys. We included in the catalog the sources with an
edge-darkened radio morphology, redshift $\leq 0.15$, and extending (at the
sensitivity of the FIRST images) to a radius $r$ larger than 30 kpc from the
center of the host. We also selected an additional sample (sFRICAT) of 14
smaller (10 $<r<$ 30 kpc) FRIs, limiting to $z<0.05$. The hosts of the FRICAT
sources are all luminous ($-21 \gtrsim M_r \gtrsim -24$), red early-type
galaxies with black hole masses in the range $10^8 \lesssim M_{\rm BH} \lesssim
3\times10^9 M_\odot$; the spectroscopic classification based on the optical
emission line ratios indicates that they are all low excitation galaxies.
Sources in the FRICAT are then indistinguishable from the FRIs belonging to the
Third Cambridge Catalogue of Radio Sources (3C) on the basis of their optical
properties. Conversely, while the 3C-FRIs show a strong positive trend between
radio and [OIII] emission line luminosity, these two quantities are unrelated
in the FRICAT sources; at a given line luminosity, they show radio luminosities
spanning about two orders of magnitude and extending to much lower ratios
between radio and line power than 3C-FRIs. Our main conclusion is that the
3C-FRIs just represent the tip of the iceberg of a much larger and diverse
population of FRIs.


title:
The Next Generation Virgo Cluster Survey (NGVS). XXIV. The Red Sequence
  to $\sim$10$^6$ L$_{\odot}$ and Comparisons with Galaxy Formation Models

abstract:
  We use deep optical photometry from the Next Generation Virgo Cluster Survey
[NGVS] to investigate the color-magnitude diagram for the galaxies inhabiting
the core of this cluster. The sensitivity of the NGVS imaging allows us to
continuously probe galaxy colors over a factor of $\sim 2 \times 10^5$ in
luminosity, from brightest cluster galaxies to scales overlapping classical
satellites of the Milky Way [$M_{g^{\prime}}$ $\sim$ $-$9; $M_{*}$ $\sim 10^6$
M$_{\odot}$], within a single environment. Remarkably, we find the first
evidence that the RS flattens in all colors at the faint-magnitude end
[starting between $-$14 $\le$ $M_{g^{\prime}}$ $\le$ $-$13, around $M_{*}$
$\sim 4 \times 10^7$ M$_{\odot}$], with the slope decreasing to $\sim$60% or
less of its value at brighter magnitudes. This could indicate that the stellar
populations of faint dwarfs in Virgo's core share similar characteristics [e.g.
constant mean age] over $\sim$3 mags in luminosity, suggesting that these
galaxies were quenched coevally, likely via pre-processing in smaller hosts. We
also compare our results to galaxy formation models, finding that the RS in
model clusters have slopes at intermediate magnitudes that are too shallow, and
in the case of semi-analytic models, do not reproduce the flattening seen at
both extremes [bright/faint] of the Virgo RS. Deficiencies in the chemical
evolution of model galaxies likely contribute to the model-data discrepancies
at all masses, while overly efficient quenching may also be a factor at dwarf
scales. Deep UV and near-IR photometry are required to unambiguously diagnose
the cause of the faint-end flattening.


title: Einstein gravity 3-point functions from conformal field theory

abstract:
  We study stress tensor correlation functions in four-dimensional conformal
field theories with large $N$ and a sparse spectrum. Theories in this class are
expected to have local holographic duals, so effective field theory in anti-de
Sitter suggests that the stress tensor sector should exhibit universal,
gravity-like behavior. At the linearized level, the hallmark of locality in the
emergent geometry is that stress tensor three-point functions $\langle
TTT\rangle$, normally specified by three constants, should approach a universal
structure controlled by a single parameter as the gap to higher spin operators
is increased. We demonstrate this phenomenon by a direct CFT calculation.
Stress tensor exchange, by itself, violates causality and unitarity unless the
three-point functions are carefully tuned, and the unique consistent choice
exactly matches the prediction of Einstein gravity. Under some assumptions
about the other potential contributions, we conclude that this structure is
universal, and in particular, that the anomaly coefficients satisfy $a\approx
c$ as conjectured by Camanho et al. The argument is based on causality of a
four-point function, with kinematics designed to probe bulk locality, and
invokes the chaos bound of Maldacena, Shenker, and Stanford.


title:
Galaxy gas as obscurer: I. GRBs x-ray galaxies and find a N_H ~ M*
  relation

abstract:
  An important constraint for galaxy evolution models is how much gas resides
in galaxies, in particular at the peak of star formation z=1-3. We attempt a
novel approach by letting long-duration Gamma Ray Bursts (LGRBs) x-ray their
host galaxies and deliver column densities to us. This requires a good
understanding of the obscurer and biases introduced by incomplete follow-up
observations. We analyse the X-ray afterglow of all 844 Swift LGRBs to date for
their column density $N_H$. To derive the population properties we propagate
all uncertainties in a consistent Bayesian methodology. The $N_H$ distribution
covers the $10^{20-23}\mathrm{cm}^{-2}$ range and shows no evolutionary effect.
Higher obscurations, e.g. Compton-thick columns, could have been detected but
are not observed. The $N_H$ distribution is consistent with sources randomly
populating a ellipsoidal gas cloud of major axis
$N_H^\text{major}=10^{23}\mathrm{cm}^{-2}$ with 0.22 dex intrinsic scatter
between objects. The unbiased SHOALS survey of afterglows and hosts allows us
to constrain the relation between Spitzer-derived stellar masses and X-ray
derived column densities $N_H$. We find a well-constrained powerlaw relation of
$N_H=10^{21.7}\mathrm{cm}^{-2}\times\left(M_{\star}/10^{9.5}M_{\odot}\right)^{1/3}$,
with 0.5 dex intrinsic scatter between objects. The Milky Way and the
Magellanic clouds also follow this relation. From the geometry of the obscurer,
its stellar mass dependence and comparison with local galaxies we conclude that
LGRBs are primarily obscured by galaxy-scale gas. Ray tracing of simulated
Illustris galaxies reveals a relation of the same normalisation, but a steeper
stellar-mass dependence and mild redshift evolution. Our new approach provides
valuable insight into the gas residing in high-redshift galaxies.


title:
Galaxy gas as obscurer: II. Separating the galaxy-scale and nuclear
  obscurers of Active Galactic Nuclei

abstract:
  The "torus" obscurer of Active Galactic Nuclei (AGN) is poorly understood in
terms of its density, substructure and physical mechanisms. Large X-ray surveys
provide model boundary constraints, for both Compton-thin and Compton-thick
levels of obscuration, as obscured fractions are mean covering factors
$f_{\text{cov}}$. However, a major remaining uncertainty is host galaxy
obscuration. In Paper I we discovered a relation of $N_H \propto
M_{\star}^{1/3}$ for the obscuration of galaxy-scale gas. Here we apply this
observational relation to the AGN population, and find that galaxy-scale gas is
responsible for a luminosity-independent fraction of Compton-thin AGN, but does
not produce Compton-thick columns. With the host galaxy obscuration understood,
we present a model of the remaining, nuclear obscurer which is consistent with
a range of observations. Our radiation-lifted torus model consists of a
Compton-thick component ($f_{\text{cov}}\sim35\%$) and a Compton-thin component
($f_{\text{cov}}\sim40\%$), which depends on both black hole mass and
luminosity. This provides a useful summary of observational constraints for
torus modellers who attempt to reproduce this behaviour. It can also be
employed as a sub-grid recipe in cosmological simulations which do not resolve
the torus. We also investigate host-galaxy X-ray obscuration inside
cosmological, hydro-dynamic simulations (EAGLE, Illustris). The obscuration
from ray-traced galaxy gas can agree with observations, but is highly sensitive
to the chosen feedback assumptions.


title: Kilonovae

abstract:
  The mergers of double neutron star (NS-NS) and black hole (BH)-NS binaries
are promising gravitational wave (GW) sources for Advanced LIGO and future GW
detectors. The neutron-rich ejecta from such merger events undergoes rapid
neutron capture (r-process) nucleosynthesis, enriching our Galaxy with rare
heavy elements like gold and platinum. The radioactive decay of these unstable
nuclei also powers a rapidly evolving, supernova-like transient known as a
"kilonova". Kilonovae provide an approximately isotropic electromagnetic
counterpart to the GW signal, which also provides a unique and direct probe of
an important, if not dominant, r-process site. This handbook reviews the
history and physics of kilonovae, leading to the current paradigm of week-long
emission with a spectral peak at near-infrared wavelengths. Using a simple
light curve model to illustrate the basic physics, I introduce potentially
important variations on this canonical picture, including: ~day-long optical
("blue") emission from lanthanide-free components of the ejecta; ~hours-long
precursor UV/blue emission, powered by the decay of free neutrons in the
outermost ejecta layers; and enhanced emission due to energy input from a
long-lived central engine, such as an accreting BH or millisecond magnetar. I
assess the prospects of detecting kilonovae following future GW detections of
NS-NS/BH-NS mergers in light of the recent follow-up campaign of the LIGO
binary BH-BH mergers.


title:
A Second Decoupling Between Merging Binary Black Holes and the Inner
  Disc--Impact on the Electromagnetic Counterpart

abstract:
  The coalescence of two supermassive black holes (SMBHs) produces powerful
gravitational-wave (GW) radiation and, if gas is present in the vicinity, also
an electromagnetic (EM) counterpart. In the standard picture, an EM outburst
will be produced when the binary "decouples" from the circum-binary disc and
starts "squeezing" the disc inside the secondary orbit, resulting in its quick
accretion on to the primary black hole. Here we use analytical arguments and
numerical simulations to show that the disc within about $20~R_S$ of a SMBH
survives the merger without being depleted. The reason is a "second
decoupling": the inner disc thickens due to tidal heating and inefficient
cooling, effectively decoupling from the interaction of the binary. We show
that this second decoupling quenches the heating sources in the disc ${\cal
O}(10^2)$ days before coalescence. This will render the peak UV/X-ray
luminosity significantly weaker than previously thought. After the merger, the
residual disc cools down and expands, merging with the outer disc rather than
being completely accreted. This results in continuous EM emission, hindering
the detection of the cut-off and re-brightening proposed in earlier studies.


title:
Weak lensing measurement of the mass-richness relation using the SDSS
  database

abstract:
  We study the mass-richness relation using galaxy catalogues and images from
the Sloan Digital Sky Survey. We use two independent methods, in the first one,
we calibrate the scaling relation with weak-lensing mass estimates. In the
second procedure we apply a background subtraction technique to derive the
probability distribution, $P(M \mid N)$, that groups with $N$-members have a
virialized halo mass $M$. Lensing masses are derived in different richness bins
for two galaxy systems sets: the maxBCG catalogue and a catalogue based on a
group finder algorithm developed by Yang et al. MaxBCG results are used to test
the lensing methodology. The lensing mass-richness relation for the Yang et al.
group sample shows a good agreement with $P(M \mid N)$ obtained independently
with a straightforward procedure.


title:
Equitable retirement income tontines: Mixing cohorts without
  discriminating

abstract:
  There is growing interest in the design of pension annuities that insure
against idiosyncratic longevity risk while pooling and sharing systematic risk.
This is partially motivated by the desire to reduce capital and reserve
requirements while retaining the value of mortality credits; see for example
Piggott, Valdez and Detzel (2005) or Donnelly, Guillen and Nielsen (2014). In
this paper we generalize the natural retirement income tontine introduced by
Milevsky and Salisbury (2015) by combining heterogeneous cohorts into one pool.
We engineer this scheme by allocating tontine shares at either a premium or a
discount to par based on both the age of the investor and the amount they
invest. For example, a 55 year-old allocating $\$10,000$ to the tontine might
be told to pay $\$$200 per share and receive 50 shares, while a 75 year-old
allocating $\$8,000$ might pay $\$$40 per share and receive 200 shares. They
would all be mixed together into the same tontine pool and each tontine share
would have equal income rights. The current paper addresses existence and
uniqueness issues and discusses the conditions under which this scheme can be
constructed equitably -- which is distinct from fairly -- even though it isn't
optimal for any cohort. As such, this also gives us the opportunity to compare
and contrast various pooling schemes that have been proposed in the literature
and to differentiate between arrangements that are socially equitable, vs.
actuarially fair vs. economically optimal.


title:
Improved Dynamical Constraints on the Mass of the central Black Hole in
  NGC 404

abstract:
  We explore the nucleus of the nearby 10$^9M_{\odot}$~early-type galaxy
(ETGs), NGC~404, using Hubble Space Telescope (HST)/STIS spectroscopy and WFC3
imaging. We first present evidence for nuclear variability in UV, optical, and
infrared filters over a time period of 15~years. This variability adds to the
already substantial evidence for an accreting black hole at the center of
NGC~404. We then redetermine the dynamical black hole mass in NGC~404 including
modeling of the nuclear stellar populations. We combine HST/STIS spectroscopy
with WFC3 images to create a local color-$M/L$~relation derived from stellar
population modeling of the STIS data. We then use this to create a mass model
for the nuclear region. We use Jeans modeling to fit this mass model to
adaptive optics (AO) stellar kinematic observations from Gemini/NIFS. From our
stellar dynamical modeling, we find a 3$\sigma$ upper limit on the black hole
mass of $1.5\times10^5M_{\odot}$. Given the accretion evidence for a black
hole, this upper limit makes NGC~404 the lowest mass central black hole with
dynamical mass constraints. We find that the kinematics of H$_2$ emission line
gas show evidence for non-gravitational motions preventing the use of gas
dynamical modeling to constrain the black hole mass. Our stellar population
modeling also reveals that the central, counter-rotating region of the nuclear
cluster is dominated by $\sim$1~Gyr old populations.


title: Detecting Breast Cancer using a Compressive Sensing Unmixing Algorithm

abstract:
  Traditional breast cancer imaging methods using microwave Nearfield Radar
Imaging (NRI) seek to recover the complex permittivity of the tissues at each
voxel in the imaging region. This approach is suboptimal, in that it does not
directly consider the permittivity values that healthy and cancerous breast
tissues typically have. In this paper, we describe a novel unmixing algorithm
for detecting breast cancer. In this approach, the breast tissue is separated
into three components, low water content (LWC), high water content (HWC), and
cancerous tissues, and the goal of the optimization procedure is to recover the
mixture proportions for each component. By utilizing this approach in a hybrid
DBT / NRI system, the unmixing reconstruction process can be posed as a sparse
recovery problem, such that compressive sensing (CS) techniques can be
employed. A numerical analysis is performed, which demonstrates that cancerous
lesions can be detected from their mixture proportion under the appropriate
conditions.


title:
Extremal behaviour of hitting a cone by correlated Brownian motion with
  drift

abstract:
  This paper derives an exact asymptotic expression for \[
\mathbb{P}_{\mathbf{x}_u}\{\exists_{t\ge0} \mathbf{X}(t)- \boldsymbol{\mu}t\in
\mathcal{U} \}, \ \ {\rm as}\ \ u\to\infty, \] where
$\mathbf{X}(t)=(X_1(t),\ldots,X_d(t))^\top,t\ge0$ is a correlated
$d$-dimensional Brownian motion starting at the point
$\mathbf{x}_u=-\boldsymbol{\alpha}u$ with $\boldsymbol{\alpha}\in
\mathbb{R}^d$, $\boldsymbol{\mu} \in \mathbb{R}^d$ and
$\mathcal{U}=\prod_{i=1}^d [0,\infty)$. The derived asymptotics depends on the
solution of an underlying multidimensional quadratic optimization problem with
constraints, which leads in some cases to dimension-reduction of the considered
problem. Complementary, we study asymptotic distribution of the conditional
first passage time to $\mathcal{U}$, which depends on the dimension-reduction
phenomena.


title:
A studentized permutation test for three-arm trials in the 'gold
  standard' design

abstract:
  The 'gold standard' design for three-arm trials refers to trials with an
active control and a placebo control in addition to the experimental treatment
group. This trial design is recommended when being ethically justifiable and it
allows the simultaneous comparison of experimental treatment, active control,
and placebo. Parametric testing methods have been studied plentifully over the
past years. However, these methods often tend to be liberal or conservative
when distributional assumptions are not met particularly with small sample
sizes. In this article, we introduce a studentized permutation test for testing
non-inferiority and superiority of the experimental treatment compared to the
active control in three-arm trials in the `gold standard' design. The
performance of the studentized permutation test for finite sample sizes is
assessed in a Monte-Carlo simulation study under various parameter
constellations. Emphasis is put on whether the studentized permutation test
meets the target significance level. For comparison purposes, commonly used
Wald-type tests are included in the simulation study. The simulation study
shows that the presented studentized permutation test for assessing
non-inferiority in three-arm trials in the 'gold standard' design outperforms
its competitors for count data. The methods discussed in this paper are
implemented in the R package ThreeArmedTrials which is available on the
comprehensive R archive network (CRAN).


title:
Physics of Galactic Metals: Evolutionary Effects due to Production,
  Distribution, Feedback & Interaction with Black Holes

abstract:
  We ask how the inclusion of various physical heating processes due to the
metal content of gas affect the evolution of massive galaxies and compute a
suite of cosmological hydrodynamical simulations that follow these systems and
their supermassive black holes. We use a smoothed particle hydrodynamics code
with a pressure-entropy formulation and a more accurate treatment of the metal
production, turbulent diffusion and cooling rate based on individual element
abundances. The feedback models include (1) AGN feedback via high velocity BAL
winds and Compton/photoionization heating, (2) explicit stellar feedback from
multiple processes including powerful winds from supernova events, stellar
winds from young massive stars and AGB stars as well as radiative heating
within Stromgren spheres around massive stars, and (3) additional heating
effects due to the presence of metals including grain photoelectric heating,
metallicity dependent X-ray heating by nearby accreting black holes and from
the cosmic X-ray background, which are the major improvement in our feedback
model. With a suite of zoom-in simulations of 30 halos with $M_{vir} \sim
10^{12-13.4}$, we show that energy and momentum budget from all feedback
effects generate realistic galaxy properties. We explore the detailed role of
each feedback model with three additional sets of simulations with varying
input physics. We show that the metal induced heating mechanisms reduce the
fraction of accreted stellar material by mainly suppressing the growth of
diffuse small stellar systems at high redshift but overall have a relatively
minor effect on the final stellar and gas properties of massive galaxies. The
inclusion of AGN feedback significantly improves the ability of our
cosmological simulations to yield realistic gas and stellar properties of
massive galaxies with reasonable fraction of the final stellar mass accreted
from other galaxies.


title:
How formation time-scales affect the period dependence of the transition
  between rocky super-Earths and gaseous sub-Neptunes and implications for
  $\eta_\oplus$

abstract:
  One of the most significant advances by NASA's ${\mathit Kepler}$ Mission was
the discovery of an abundant new population of highly irradiated planets with
sizes between the Earth and Neptune. Subsequent analysis showed that at ~1.5
Earth radii there is a transition from a population of predominantly rocky
super-Earths to non-rocky sub-Neptunes, which must have substantial volatile
envelopes. Determining the origin of these highly irradiated rocky planets will
be critical to our understanding of low-mass planet formation and the frequency
of potentially habitable Earth-like planets. These short-period rocky
super-Earths could simply be the stripped cores of sub-Neptunes, which have
lost their envelopes due to atmospheric photo-evaporation or other processes,
or they might instead be a separate population of inherently rocky planets,
which never had significant envelopes. Using models of atmospheric
photo-evaporation, we show that if most bare rocky planets are the evaporated
cores of sub-Neptunes then the transition radius should decrease as surveys
push to longer orbital periods, since on wider orbits only planets with smaller
less massive cores can be stripped. On the other hand, if most rocky planets
formed after their disks dissipate then these planets will have formed without
initial gaseous envelopes. In this case, we use N-body simulations of planet
formation to show that the transition radius should increase with orbital
period, due to the increasing solid mass available in their disks. Moreover, we
show that distinguishing between these two scenarios should be possible in
coming years with radial velocity follow-up of planets found by TESS. Finally,
we discuss the broader implications of this work for current efforts to measure
$\eta_{\mathrm{\oplus}}$, which may yield significant overestimates if most
rocky planets form as evaporated cores.


title:
Searches for continuous gravitational waves from Scorpius X-1 and XTE
  J1751-305 in LIGO's sixth science run

abstract:
  Scorpius X-1 (Sco X-1) and X-ray transient (XTE) J1751-305 are Low-Mass X-ray
Binaries (LMXBs) that may emit continuous gravitational waves detectable in the
band of ground-based interferometric observatories. Neutron stars in LMXBs
could reach a torque-balance steady-state equilibrium in which angular momentum
addition from infalling matter from the binary companion is balanced by angular
momentum loss, conceivably due to gravitational-wave emission. Torque-balance
predicts a scale for detectable gravitational-wave strain based on observed
X-ray flux. This paper describes a search for Sco X-1 and XTE J1751-305 in LIGO
Science Run 6 data using the TwoSpect algorithm, based on searching for orbital
modulations in the frequency domain. While no detections are claimed, upper
limits on continuous gravitational-wave emission from Sco X-1 are obtained,
spanning gravitational-wave frequencies from 40 to 2040 Hz and projected
semi-major axes from 0.90 to 1.98 light-seconds. These upper limits are
injection validated, equal any previous set in initial LIGO data, and extend
over a broader parameter range. At optimal strain sensitivity, achieved at 165
Hz, the 95% confidence level random-polarization upper limit on dimensionless
strain $h_0$ is approximately $1.8 \times 10^{-24}$. Closest approach to the
torque-balance limit, within a factor of 27, is also at 165 Hz. These are the
first upper limits known to date on $r$-mode emission from this XTE source.
Upper limits are set in particular narrow frequency bands of interest for
J1751-305. The TwoSpect method will be used in upcoming searches of Advanced
LIGO and Virgo data.


title: The unexplored landscape of two-body resonances

abstract:
  We propose a strategy for searching for theoretically-unanticipated new
physics which avoids a large trials factor by focusing on experimental
strengths. Searches for resonances decaying into pairs of visible particles are
experimentally very powerful due to the localized mass peaks and have a rich
history of discovery. Yet, due to a focus on subsets of theoretically-motivated
models, the landscape of such resonances is far from thoroughly explored. We
survey the existing set of searches, identify untapped experimental
opportunities and discuss the theoretical constraints on models which would
generate such resonances.


title: Averaging over Heegner points in the hyperbolic circle problem

abstract:
  For $\Gamma={\hbox{PSL}_2( {\mathbb Z})}$ the hyperbolic circle problem aims
to estimate the number of elements of the orbit $\Gamma z$ inside the
hyperbolic disc centered at $z$ with radius $\cosh^{-1}(X/2)$. We show that, by
averaging over Heegner points $z$ of discriminant $D$, Selberg's error term
estimate can be improved, if $D$ is large enough. The proof uses bounds on
spectral exponential sums, and results towards the sup-norm conjecture of
eigenfunctions, and the Lindel\"of conjecture for twists of the $L$-functions
attached to Maa{\ss} cusp forms.


title:
Neural-like computing with populations of superparamagnetic basis
  functions

abstract:
  In neuroscience, population coding theory demonstrates that neural assemblies
can achieve fault-tolerant information processing. Mapped to nanoelectronics,
this strategy could allow for reliable computing with scaled-down, noisy,
imperfect devices. Doing so requires that the population components form a set
of basis functions in terms of their response functions to inputs, offering a
physical substrate for calculating. For this purpose, the responses of the
nanodevices should be non-linear, and each tuned to different values of the
input. These strong requirements have prevented a demonstration of population
coding with nanodevices. Here, we show that nanoscale magnetic tunnel junctions
can be assembled to meet these requirements. We demonstrate experimentally that
a population of nine junctions can implement a basis set of functions,
providing the data to achieve, for example, the generation of cursive letters.
We design hybrid magnetic-CMOS systems based on interlinked populations of
junctions and show that they can learn to realize non-linear
variability-resilient transformations with a low imprint area and low power.


title:
High Dynamic Range X-ray Detector Pixel Architectures Utilizing Charge
  Removal

abstract:
  Several charge integrating CMOS pixel front-ends utilizing charge removal
techniques have been fabricated to extend dynamic range for x-ray diffraction
applications at synchrotron sources and x-ray free electron lasers (XFELs). The
pixels described herein build on the Mixed Mode Pixel Array Detector (MM-PAD)
framework, developed previously by our group to perform high dynamic range
imaging. These new pixels boast several orders of magnitude improvement in
maximum flux over the MM-PAD, which is capable of measuring a sustained flux in
excess of 10$^{8}$ x-rays/pixel/second while maintaining sensitivity to smaller
signals, down to single x-rays. To extend dynamic range, charge is removed from
the integration node of the front-end amplifier without interrupting
integration. The number of times this process occurs is recorded by a digital
counter in the pixel. The parameter limiting full well is thereby shifted from
the size of an integration capacitor to the depth of a digital counter. The
result is similar to that achieved by counting pixel array detectors, but the
integrators presented here are designed to tolerate a sustained flux >10$^{11}$
x-rays/pixel/second. Pixel front-end linearity was evaluated by direct current
injection and results are presented. A small-scale readout ASIC utilizing these
pixel architectures has been fabricated and the use of these architectures to
increase single x-ray pulse dynamic range at XFELs is discussed briefly.


title:
The problem of coexistence of several non-Hermitian observables in
  PT-symmetric quantum mechanics

abstract:
  During the recent developments of quantum theory it has been clarified that
the observable quantities (like energy or position) may be represented by
operators (with real spectra) which are manifestly non-Hermitian. The
mathematical consistency of the resulting models of stable quantum systems
requires a reconstruction of an alternative, amended, physical inner product of
states. We point out the less known fact that for more than one observable the
task is not always feasible. The difficulty is re-analyzed and its elementary
linear-algebraic interpretation and treatment are outlined.


title: The Momentum Distribution of Liquid $^3$He

abstract:
  We present high-resolution neutron Compton scattering measurements of liquid
$^3$He below its renormalized Fermi temperature. Theoretical predictions are in
excellent agreement with the experimental data when instrumental resolution and
final state effects are accounted for. Our results resolve the long-standing
inconsistency between theoretical and experimental estimates of the average
atomic kinetic energy.


title: Neutralino pair production via photon-photon collisions at the ILC

abstract:
  We provide complete one-loop predictions for the direct production of the
neutralino pairs via photon-photon collisions which appears for the first time
at one-loop level in the minimal supersymmetric standard model at the
International Linear Collider. We present a comprehensive investigation of the
dependence of total cross section on the center-of-mass energy and the
tan$\beta$ for three different scenarios based on gaugino/Higgsino fractions of
the neutralinos. Furthermore, by investigating the behavior with the most
relevant parameters $\mu$ and $M_2$, we exhibit regions of the parameter space
where the enhancement of the cross section is large enough to be detectable at
linear colliders. Our analysis shows that the corresponding production cross
section reaches its highest values when the lightest neutralino
$\widetilde{\chi}_{1}^0$ has a dominant Higgsino component and/or the
next-to-lightest neutralino $\widetilde{\chi}_{2}^0$ has a dominant gaugino
component.


title:
Longitudinal optical and spin-Hall conductivities of Rashba conducting
  strips coupled to ferro- and antiferromagnetic layers

abstract:
  A system composed of a conducting planar strip with Rashba spin-orbit
coupling (RSOC), magnetically coupled to a layer of localized magnetic moments,
at equilibrium, is studied within a microscopic Hamiltonian with numerical
techniques at zero temperature in the clean limit. In particular, transport
properties for the cases of ferromagnetic (FM) and antiferromagnetic (AFM)
coupled layers are computed in linear response on strips of varying width. Some
behaviors observed for these properties are consistent with the ones observed
for the corresponding Rashba helical currents. The case of uncoupled Rashba
strips is also studied for comparison. In the case of Rashba strips coupled to
an AFM localized order, results for the longitudinal dc conductivity, for small
strip widths, suggest the proximity to a metal-insulator transition. More
interesting, in the proximity of this transition, and in general at
intermediate values of the RSOC, it is observed a large spin-Hall conductivity
that is two orders of magnitude larger than the one for the FM order for the
same values of the RSOC and strip widths. There are clearly two different
regimes for small and for large RSOC, which is also present in the behavior of
Rashba helical currents. Different contributions to the optical and the
spin-Hall conductivities, according to a new classification of inter- or
intra-band origin proposed for planar strips in the clean limit, or coming from
the hopping or spin-orbit terms of the Hamiltonian, are examined. Finally, the
effects of different orientation of the coupled magnetic moments will be also
studied.


title:
Moment Matching Based Conjugacy Approximation for Bayesian Ranking and
  Selection

abstract:
  We study the conjugacy approximation method in the context of Bayesian
ranking and selection with unknown correlations. Under the assumption of
normal-inverse-Wishart prior distribution, the posterior distribution remains a
normal-inverse-Wishart distribution thanks to the conjugacy property when all
alternatives are sampled at each step. However, this conjugacy property no
longer holds if only one alternative is sampled at a time, an appropriate
setting when there is a limited budget on the number of samples. We propose two
new conjugacy approximation methods based on the idea of moment matching. Both
of them yield closed-form Bayesian prior updating formulas. This updating
formula can then be combined with the knowledge gradient algorithm under the
"value of information" framework. We conduct computational experiments to show
the superiority of the proposed conjugacy approximation methods, including
applications in wind farm placement and computer model calibration.


title: On definable multifunctions and {\L}ojasiewicz inequalities

abstract:
  We investigate several possibilities of obtaining a {\L}ojasiewicz inequality
for definable multifunctions and give some examples of applications thereof. In
particular, we prove that the Hausdorff distance and its extension to closed
sets is definable when composed with definable multifunctions. This allows us
to obtain {\L}ojasiewicz-type inequalities for definable multifunctions
obtained from Clarke's subgradient or the tangent cone. The paper ends with a
{\L}ojasiewicz-type subgradient inequality in the spirit of
Bolte-Daniilidis-Lewis-Shiota or Ph\d{a}m.


title:
Inchworm Monte Carlo for exact non-adiabatic dynamics II. Benchmarks and
  comparison with established methods

abstract:
  In this second paper of a two part series, we present extensive benchmark
results for two different inchworm Monte Carlo expansions for the spin-boson
model. Our results are compared to previously developed numerically exact
approaches for this problem. A detailed discussion of convergence and error
propagation is presented. Our results and analysis allow for an understanding
of the benefits and drawbacks of inchworm Monte Carlo compared to other
approaches for exact real-time non-adiabatic quantum dynamics.


title:
Understanding the Non-Convergence of Agricultural Futures via Stochastic
  Storage Costs and Timing Options

abstract:
  This paper studies the market phenomenon of non-convergence between futures
and spot prices in the grains market. We postulate that the positive basis
observed at maturity stems from the futures holder's timing options to exercise
the shipping certificate delivery item and subsequently liquidate the physical
grain. In our proposed approach, we incorporate stochastic spot price and
storage cost, and solve an optimal double stopping problem to give the optimal
strategies to exercise and liquidate the grain. Our new models for stochastic
storage rates lead to explicit no-arbitrage prices for the shipping certificate
and associated futures contract. We calibrate our models to empirical futures
data during the periods of observed non-convergence, and illustrate the premium
generated by the shipping certificate.


title: Understanding the Tracking Errors of Commodity Leveraged ETFs

abstract:
  Commodity exchange-traded funds (ETFs) are a significant part of the rapidly
growing ETF market. They have become popular in recent years as they provide
investors access to a great variety of commodities, ranging from precious
metals to building materials, and from oil and gas to agricultural products. In
this article, we analyze the tracking performance of commodity leveraged ETFs
and discuss the associated trading strategies. It is known that leveraged ETF
returns typically deviate from their tracking target over longer holding
horizons due to the so-called volatility decay. This motivates us to construct
a benchmark process that accounts for the volatility decay, and use it to
examine the tracking performance of commodity leveraged ETFs. From empirical
data, we find that many commodity leveraged ETFs underperform significantly
against the benchmark, and we quantify such a discrepancy via the novel idea of
\emph{realized effective fee}. Finally, we consider a number of trading
strategies and examine their performance by backtesting with historical price
data.


title: Programming Heterogeneous Systems from an Image Processing DSL

abstract:
  Specialized image processing accelerators are necessary to deliver the
performance and energy efficiency required by important applications in
computer vision, computational photography, and augmented reality. But
creating, "programming,"and integrating this hardware into a hardware/software
system is difficult. We address this problem by extending the image processing
language, Halide, so users can specify which portions of their applications
should become hardware accelerators, and then we provide a compiler that uses
this code to automatically create the accelerator along with the "glue" code
needed for the user's application to access this hardware. Starting with Halide
not only provides a very high-level functional description of the hardware, but
also allows our compiler to generate the complete software program including
the sequential part of the workload, which accesses the hardware for
acceleration. Our system also provides high-level semantics to explore
different mappings of applications to a heterogeneous system, with the added
flexibility of being able to map at various throughput rates.
  We demonstrate our approach by mapping applications to a Xilinx Zynq system.
Using its FPGA with two low-power ARM cores, our design achieves up to 6x
higher performance and 8x lower energy compared to the quad-core ARM CPU on an
NVIDIA Tegra K1, and 3.5x higher performance with 12x lower energy compared to
the K1's 192-core GPU.


title:
Biophysical comparison of ATP-driven proton pumping mechanisms suggests
  a kinetic advantage for the rotary process depending on coupling ratio

abstract:
  ATP-driven proton pumps, which are critical to the operation of a cell,
maintain cytosolic and organellar pH levels within a narrow functional range.
These pumps employ two very different mechanisms: an elaborate rotary mechanism
used by V-ATPase H+ pumps, and a simpler alternating access mechanism used by
P-ATPase H+ pumps. Why are two different mechanisms used to perform the same
function? Systematic analysis, without parameter fitting, of kinetic models of
the rotary, alternating access and other possible mechanisms suggest that, when
the ratio of protons transported per ATP hydrolyzed exceeds one, the
one-at-a-time proton transport by the rotary mechanism is faster than other
possible mechanisms across a wide range of driving conditions. When the ratio
is one, there is no intrinsic difference in the free energy landscape between
mechanisms, and therefore all mechanisms can exhibit the same kinetic
performance. To our knowledge all known rotary pumps have an H+:ATP ratio
greater than one, and all known alternating access ATP-driven proton pumps have
a ratio of one. Our analysis suggests a possible explanation for this apparent
relationship between coupling ratio and mechanism. When the conditions under
which the pump must operate permit a coupling ratio greater than one, the
rotary mechanism may have been selected for its kinetic advantage. On the other
hand, when conditions require a coupling ratio of one or less, the alternating
access mechanism may have been selected for other possible advantages resulting
from its structural and functional simplicity.


title:
On Achievability for Downlink Cloud Radio Access Networks with Base
  Station Cooperation

abstract:
  This work investigates the downlink of a cloud radio access network (C-RAN)
in which a central processor communicates with two mobile users through two
base stations (BSs). The BSs act as relay nodes and cooperate with each other
through error-free rate-limited links. We develop and analyze two coding
schemes for this scenario. The first coding scheme is based on Liu-Kang scheme
for C-RANs without BS cooperation; and extends it to scenarios allowing
conferencing between the BSs. Among few other features, our new coding scheme
enables arbitrary correlation among the auxiliary codewords that are recovered
by the BSs. It also introduces common codewords to be described to both BSs.
For the analysis of this coding scheme, we extend the multivariate covering
lemma to non-Cartesian product sets, thereby correcting an erroneous
application of this lemma in Liu-Kang's related work. We highlight key aspects
of this scheme by studying three important instances of it. The second coding
scheme extends the so-called compression scheme that was originally developed
for memoryless Gaussian C-RANs without BS cooperation to general discrete
memoryless C-RANs with BS cooperation. We show that this scheme subsumes the
original compression scheme when applied to memoryless Gaussian C-RAN models.
In the analysis of this scheme, we also highlight important connections with
the so-called distributed decode--forward scheme, and refine the approximate
capacity of a general $N$-BS $L$-user C-RAN model in the memoryless Gaussian
case.


title: Weighted Hurwitz numbers and topological recursion: an overview

abstract:
  Multiparametric families of hypergeometric $\tau$-functions of KP or Toda
type serve as generating functions for weighted Hurwitz numbers, providing
weighted enumerations of branched covers of the Riemann sphere. A graphical
interpretation of the weighting is given in terms of constellations mapped onto
the covering surface. The theory is placed within the framework of topological
recursion, with the Baker function at ${\bf t} ={\bf 0}$ shown to satisfy the
quantum spectral curve equation, whose classical limit is rational. A basis for
the space of formal power series in the spectral variable is generated that is
adapted to the Grassmannian element associated to the $\tau$-function.
Multicurrent correlators are defined in terms of the $\tau$-function and shown
to provide an alternative generating function for weighted Hurwitz numbers.
Fermionic VEV representations are provided for the adapted bases, pair
correlators and multicurrent correlators. Choosing the weight generating
function as a polynomial, and restricting the number of nonzero "second" KP
flow parameters in the Toda $\tau$-function to be finite implies a finite rank
covariant derivative equation with rational coefficients satisfied by a finite
"window" of adapted basis elements. The pair correlator is shown to provide a
Christoffel-Darboux type finite rank integrable kernel, and the WKB series
coefficients of the associated adjoint system are computed recursively, leading
to topological recursion relations for the generators of the weighted Hurwitz
numbers.

categories: math-ph hep-th math.AG math.CO math.MP nlin.SI


title:
Probabilistic Model Checking for Complex Cognitive Tasks -- A case study
  in human-robot interaction

abstract:
  This paper proposes to use probabilistic model checking to synthesize optimal
robot policies in multi-tasking autonomous systems that are subject to
human-robot interaction. Given the convincing empirical evidence that human
behavior can be related to reinforcement models, we take as input a
well-studied Q-table model of the human behavior for flexible scenarios. We
first describe an automated procedure to distill a Markov decision process
(MDP) for the human in an arbitrary but fixed scenario. The distinctive issue
is that -- in contrast to existing models -- under-specification of the human
behavior is included. Probabilistic model checking is used to predict the
human's behavior. Finally, the MDP model is extended with a robot model.
Optimal robot policies are synthesized by analyzing the resulting two-player
stochastic game. Experimental results with a prototypical implementation using
PRISM show promising results.


title:
Testing gravity on large scales by combining weak lensing with galaxy
  clustering using CFHTLenS and BOSS CMASS

abstract:
  We measure a combination of gravitational lensing, galaxy clustering, and
redshift-space distortions called $E_G$. The quantity $E_G$ probes both parts
of metric potential and is insensitive to galaxy bias and $\sigma_8$. These
properties make it an attractive statistic to test $\Lambda$CDM, General
Relativity and its alternate theories. We have combined CMASS DR11 with
CFHTLenS and recent measurements of $\beta$ from RSD analysis, and find $E_G(z
= 0.57) = 0.42 \pm 0.056$, an 13\% measurement in agreement with the prediction
of general relativity $E_G(z = 0.57) = 0.396 \pm 0.011$ using the Planck 2015
cosmological parameters. We have corrected our measurement for various
observational and theoretical systematics. Our measurement is consistent with
the first measurement of $E_G$ using CMB lensing in place of galaxy lensing
(Pullen et. al. 2015a) at small scales, but shows 2.8$\sigma$ tension when
compared with their final results including large scales. This analysis with
future surveys will provide improved statistical error and better control over
systematics to test General Relativity and its alternate theories.


title: ESCAPE: Efficiently Counting All 5-Vertex Subgraphs

abstract:
  Counting the frequency of small subgraphs is a fundamental technique in
network analysis across various domains, most notably in bioinformatics and
social networks. The special case of triangle counting has received much
attention. Getting results for 4-vertex or 5-vertex patterns is highly
challenging, and there are few practical results known that can scale to
massive sizes.
  We introduce an algorithmic framework that can be adopted to count any small
pattern in a graph and apply this framework to compute exact counts for
\emph{all} 5-vertex subgraphs. Our framework is built on cutting a pattern into
smaller ones, and using counts of smaller patterns to get larger counts.
Furthermore, we exploit degree orientations of the graph to reduce runtimes
even further. These methods avoid the combinatorial explosion that typical
subgraph counting algorithms face. We prove that it suffices to enumerate only
four specific subgraphs (three of them have less than 5 vertices) to exactly
count all 5-vertex patterns.
  We perform extensive empirical experiments on a variety of real-world graphs.
We are able to compute counts of graphs with tens of millions of edges in
minutes on a commodity machine. To the best of our knowledge, this is the first
practical algorithm for $5$-vertex pattern counting that runs at this scale. A
stepping stone to our main algorithm is a fast method for counting all
$4$-vertex patterns. This algorithm is typically ten times faster than the
state of the art $4$-vertex counters.


title:
A Survey for New Members of the Taurus Star-Forming Region with the
  Sloan Digital Sky Survey

abstract:
  Previous studies have found that ~1 deg2 fields surrounding the stellar
aggregates in the Taurus star-forming region exhibit a surplus of solar-mass
stars relative to denser clusters like IC~348 and the Orion Nebula Cluster. To
test whether this difference reflects mass segregation in Taurus or a variation
in the IMF, we have performed a survey for members of Taurus across a large
field (~40 deg2) that was imaged by the Sloan Digital Sky Survey (SDSS). We
obtained optical and near-infrared spectra of candidate members identified with
those images and the Two Micron All Sky Survey, as well as miscellaneous
candidates that were selected with several other diagnostics of membership. We
have classified 22 of the candidates as new members of Taurus, which includes
one of the coolest known members (M9.75). Our updated census of members within
the SDSS field shows a surplus of solar-mass stars relative to clusters,
although it is less pronounced than in the smaller fields towards the stellar
aggregates that were surveyed for previously measured mass functions in Taurus.
In addition to spectra of our new members, we include in our study near-IR
spectra of roughly half of the known members of Taurus, which are used to
refine their spectral types and extinctions. We also present an updated set of
near-IR standard spectra for classifying young stars and brown dwarfs at M and
L types.


title: Scalable Planning for Energy Storage in Energy and Reserve Markets

abstract:
  Energy storage can facilitate the integration of renewable energy resources
by providing arbitrage and ancillary services. Jointly optimizing energy and
ancillary services in a centralized electricity market reduces the system's
operating cost and enhances the profitability of energy storage systems.
However, achieving these objectives requires that storage be located and sized
properly. We use a bi-level formulation to optimize the location and size of
energy storage systems which perform energy arbitrage and provide regulation
services. Our model also ensures the profitability of investments in energy
storage by enforcing a rate of return constraint. Computational tractability is
achieved through the implementation of a primal decomposition and a
subgradient-based cutting-plane method. We test the proposed approach on a
240-bus model of the Western Electricity Coordinating Council (WECC) system and
analyze the effects of different storage technologies, rate of return
requirements, and regulation market policies on ES participation on the optimal
storage investment decisions. We also demonstrate that the proposed approach
outperforms exact methods in terms of solution quality and computational
performance.


title: Learning Adaptive Parameter Tuning for Image Processing

abstract:
  The non-stationary nature of image characteristics calls for adaptive
processing, based on the local image content. We propose a simple and flexible
method to learn local tuning of parameters in adaptive image processing: we
extract simple local features from an image and learn the relation between
these features and the optimal filtering parameters. Learning is performed by
optimizing a user defined cost function (any image quality metric) on a
training set. We apply our method to three classical problems (denoising,
demosaicing and deblurring) and we show the effectiveness of the learned
parameter modulation strategies. We also show that these strategies are
consistent with theoretical results from the literature.


title:
Chimeras in Leaky Integrate-and-Fire Neural Networks: Effects of
  Reflecting Connectivities

abstract:
  The effects of nonlocal and reflecting connectivity are investigated in
coupled Leaky Integrate-and-Fire (LIF) elements, which assimilate the exchange
of electrical signals between neurons. Earlier investigations have demonstrated
that non-local and hierarchical network connectivity often induces complex
synchronization patterns and chimera states in systems of coupled oscillators.
In the LIF system we show that if the elements are non-locally linked with
positive diffusive coupling in a ring architecture the system splits into a
number of alternating domains. Half of these domains contain elements, whose
potential stays near the threshold, while they are interrupted by active
domains, where the elements perform regular LIF oscillations. The active
domains move around the ring with constant velocity, depending on the system
parameters. The idea of introducing reflecting non-local coupling in LIF
networks originates from signal exchange between neurons residing in the two
hemispheres in the brain. We show evidence that this connectivity induces novel
complex spatial and temporal structures: for relatively extensive ranges of
parameter values the system splits in two coexisting domains, one domain where
all elements stay near-threshold and one where incoherent states develop with
multileveled mean phase velocity distribution.