title: Stabilizer information inequalities from phase space distributions

abstract:
  The Shannon entropy of a collection of random variables is subject to a
number of constraints, the best-known examples being monotonicity and strong
subadditivity. It remains an open question to decide which of these "laws of
information theory" are also respected by the von Neumann entropy of many-body
quantum states. In this article, we consider a toy version of this difficult
problem by analyzing the von Neumann entropy of stabilizer states. We find that
the von Neumann entropy of stabilizer states satisfies all balanced information
inequalities that hold in the classical case. Our argument is built on the fact
that stabilizer states have a classical model, provided by the discrete Wigner
function: The phase-space entropy of the Wigner function corresponds directly
to the von Neumann entropy of the state, which allows us to reduce to the
classical case. Our result has a natural counterpart for multi-mode Gaussian
states, which sheds some light on the general properties of the construction.
We also discuss the relation of our results to recent work by Linden, Ruskai,
and Winter.


title:
Exact momentum fluctuations of an accelerated quark in N=4 super
  Yang-Mills

abstract:
  In this work we consider a heavy quark moving with constant proper
acceleration in the vacuum of any four dimensional conformal field theory. We
argue that the two-point function of its momentum fluctuations is exactly
captured by the Bremsstrahlung function that gives the total radiated power.
For the particular case of N=4 SU(N) SYM this function is exactly known, so in
this case we obtain an explicit expression for the momentum diffusion
coefficient, and check that various limits of this result are reproduced by
probe computations in AdS_5. Finally, we evaluate this transport coefficient
for a heavy quark accelerated in the vacuum of N=4 SU(3) SYM, and comment on
possible lessons of our results for the study of heavy quarks traversing the
super Yang-Mills plasma.


title: Evidence of Rocky Planetesimals Orbiting Two Hyades Stars

abstract:
  The Hyades is the nearest open cluster, relatively young and containing
numerous A-type stars; its known age, distance, and metallicity make it an
ideal site to study planetary systems around 2-3 Msun stars at an epoch similar
to the late heavy bombardment. Hubble Space Telescope far-ultraviolet
spectroscopy strongly suggests ongoing, external metal pollution in two remnant
Hyads. For ongoing accretion in both stars, the polluting material has
log[n(Si)/n(C)] > 0.2, is more carbon deficient than chondritic meteorites, and
is thus rocky. These data are consistent with a picture where rocky
planetesimals and small planets have formed in the Hyades around two
main-sequence A-type stars, whose white dwarf descendants bear the scars. These
detections via metal pollution are shown to be equivalent to infrared excesses
of Lir/L* ~ 1e-6 in the terrestrial zone of the stars.


title: Worldsheet Realization of the Refined Topological String

abstract:
  A worldsheet realization of the refined topological string is proposed in
terms of physical string amplitudes that compute generalized N=2 F-terms of the
form F_{g,n} W^{2g}Y^{2n} in the effective supergravity action. These terms
involve the chiral Weyl superfield W and a superfield Y defined as an N=2
chiral projection of a particular anti-chiral T-bar vector multiplet. In
Heterotic and Type I theories, obtained upon compactification on the
six-dimensional manifold K3xT2, T is the usual K\"ahler modulus of the T2
torus. These amplitudes are computed exactly at the one-loop level in string
theory. They are shown to reproduce the correct perturbative part of the
Nekrasov partition function in the field theory limit when expanded around an
SU(2) enhancement point of the string moduli space. The two deformation
parameters epsilon_- and epsilon_+ of the Omega-supergravity background are
then identified with the constant field-strength backgrounds for the
anti-self-dual graviphoton and self-dual gauge field of the T-bar vector
multiplet, respectively.


title: Power Spectrum Super-Sample Covariance

abstract:
  We provide a simple, unified approach to describing the impact of
super-sample covariance, or beat coupling, on power spectrum estimation in a
finite-volume survey. For a wide range of survey volumes, the sample variance
that arises from modes that are larger than the survey dominates the covariance
of power spectrum estimators for modes much smaller than the survey. The deeply
nonlinear version of this effect is known as halo sample variance. We show that
all variants are unified by the matter trispectrum of squeezed configurations
and that such configurations obey a consistency relation which relates them to
the response of the power spectrum to a change in the background density. Our
method also applies to statistics that are based on radial projections of the
density field such as weak lensing shear. While we use the halo model for an
analytic description to expose the nature of the effect, the consistency
description enables an accurate calibration of the full effect directly from
simulations. It also suggests that super-sample covariance may be viewed as an
additional interesting signal rather than excess noise.


title: Bottom-Quark Forward-Backward Asymmetry in the Standard Model and Beyond

abstract:
  We computed the bottom-quark forward-backward asymmetry at the Tevatron in
the Standard Model and for several new physics scenarios. Near the $Z$-pole,
the SM bottom asymmetry is dominated by tree level exchanges of electroweak
gauge bosons. While above the $Z$-pole, next-to-leading order QCD dominates the
SM asymmetry as was the case with the top quark forward-backward asymmetry.
Light new physics, $M_{NP} \precsim 150$ GeV, can cause significant deviations
from the SM prediction for the bottom asymmetry. The bottom asymmetry can be
used to distinguish between competing NP explanations of the top asymmetry
based on how the NP interferes with s-channel gluon and $Z$ exchange.


title: Unravelling obese black holes in the first galaxies

abstract:
  We predict the existence and observational signatures of a new class of
objects that assembled early, during the first billion years of cosmic time:
Obese Black-hole Galaxies (OBGs). OBGs are objects in which the mass of the
central black hole initially exceeds that of the stellar component of the host
galaxy, and the luminosity from black-hole accretion dominates the starlight.
From a cosmological simulation, we demonstrate that there are sites where star
formation is initially inhibited and direct-collapse black holes (DCBHs) form
due to the photo-dissociating effect of Lyman-Werner radiation on molecular
hydrogen. We show that the formation of OBGs is inevitable, because the
probability of finding the required extra-galactic environment and the right
physical conditions in a halo conducive to DCBH formation is quite high in the
early universe. We estimate an OBG number density of 0.009/Mpc^3 at z~8 and
0.03/Mpc^3 at z~6. Extrapolating from our simulation volume, we infer that the
most luminous quasars detected at z~6 likely transited through an earlier OBG
phase. We find that these primordial galaxies start off with an over-massive BH
and acquire their stellar component from subsequent merging as well as in-situ
star formation. In doing so, they inevitably go through an OBG phase dominated
by the accretion luminosity at the Eddington rate or below, released from the
growing BH. The OBG phase is characterised by an ultra-violet (UV) spectrum
with slope of beta ~ -2.3 and the absence of a Balmer Break. OBGs should also
be spatially unresolved, and are expected to be brighter than the majority of
known high-redshift galaxies. OBGs could potentially be revealed via HST
follow-up imaging of samples of brighter Lyman-break galaxies provided by
wide-area ground-based surveys such as UltraVISTA, and should be easily
uncovered and studied with instruments aboard JWST...(abridged)


title:
Fine-Structure FeII* Emission and Resonant MgII Emission in z = 1
  Star-Forming Galaxies

abstract:
  We present a study of the prevalence, strength, and kinematics of ultraviolet
FeII and MgII emission lines in 212 star-forming galaxies at z = 1 selected
from the DEEP2 survey. We find FeII* emission in composite spectra assembled on
the basis of different galaxy properties, indicating that FeII* emission is
prevalent at z = 1. In these composites, FeII* emission is observed at roughly
the systemic velocity. At z = 1, we find that the strength of FeII* emission is
most strongly modulated by dust attenuation, and is additionally correlated
with redshift, star-formation rate, and [OII] equivalent width, such that
systems at higher redshifts with lower dust levels, lower star-formation rates,
and larger [OII] equivalent widths show stronger FeII* emission. We detect MgII
emission in at least 15% of the individual spectra and we find that objects
showing stronger MgII emission have higher specific star-formation rates,
smaller [OII] linewidths, larger [OII] equivalent widths, lower dust
attenuations, and lower stellar masses than the sample as a whole. MgII
emission strength exhibits the strongest correlation with specific
star-formation rate, although we find evidence that dust attenuation and
stellar mass also play roles in the regulation of MgII emission. Future
integral field unit observations of the spatial extent of FeII* and MgII
emission in galaxies with high specific star-formation rates, low dust
attenuations, and low stellar masses will be important for probing the
morphology of circumgalactic gas.


title: The Ratio of CO to Total Gas Mass in High Redshift Galaxies

abstract:
  Walter et al. (20012) have recently identified the J=6-5, 5-4, and 2-1 CO
rotational emission lines, and [C_{II}] fine-structure emission line from the
star-forming interstellar medium in the high-redshift submillimeter source HDF
850.1, at z = 5.183. We employ large velocity gradient (LVG) modeling to
analyze the spectra of this source assuming the [C_{II}] and CO emissions
originate from (i) separate unvirialized regions, (ii) separate virialized
regions, (iii) uniformly mixed unvirialized region, and (iv) uniformly mixed
virialized regions. We present the best fit set of parameters, including for
each case the ratio $\alpha$ between the total hydrogen/helium gas mass and the
CO(1-0) line luminosity. We also present computations of the ratio of H_{2}
mass to [C_{II}] line-luminosity for optically thin conditions, for a range of
gas temperatures and densities, for direct conversion of [C_{II}]
line-luminosities to "dark-H_{2}" masses. For HDF 850.1 we find that a model in
which the CO and C^{+} are uniformly mixed in gas that is shielded from UV
radiation, requires a cosmic-ray or X-ray ionization rate of $\zeta \approx$
10^{-13} s^{-1}, plausibly consistent with the large star-formation rate
($\sim$ 10^{3} M$_{\odot}$ yr^{-1}) observed in this source. Enforcing the
cosmological constraint posed by the abundance of dark matter halos in the
standard $\Lambda$CDM cosmology and taking into account other possible
contributions to the total gas mass, we find that three of these four models
are less likely at the 2$\sigma$ level. We conclude that modeling HDF 850.1's
ISM as a collection of unvirialized molecular clouds with distinct CO and C^{+}
layers, for which $\alpha$ = 0.6 M$_{\odot}$ (K km s^{-1} pc^{2})^{-1} for the
CO to H_{2} mass-to-luminosity ratio, (similar to the standard ULIRG value), is
most consistent with the $\Lambda$CDM cosmology.


title:
CLUES to the past: Local Group progenitors amongst high-redshift Lyman
  Break Galaxies

abstract:
  We use state-of-the-art numerical simulations to explore the observability
and the expected physical properties of the progenitors of the local group
galaxies at z=6-8, within 1 billion years of the big bang. We find that the
most massive progenitors of the Milky Way (MW) and Andromeda (M31) at z=6 and 7
are predicted to have absolute UV continuum magnitudes between -17 and -18,
suggesting that their analogues lie close to the detection limits of the
deepest near-infrared surveys conducted to date (i.e. HST WFC3/IR UDF12). This
in turn confirms that the majority of currently known z=6-8 galaxies are
expected to be the seeds of present-day galaxies which are more massive than L*
spirals. We also discuss the properties of the local-group progenitors at these
early epochs, extending down to absolute magnitudes M_UV = -13. The most
massive MW/M31 progenitors at z=7 have stellar masses of about 10^7.5-8 solar
masses, stellar metallicities between 3 and 6% of the solar value, and
predicted observed UV continuum slopes between -2.4 and -2.5.


title:
Spatially Resolved Images of Dust Belt(s) Around the Planet-hosting
  Subgiant Kappa CrB

abstract:
  We present Herschel spatially resolved images of the debris disc orbiting the
subgiant Kappa CrB. Not only are these the first resolved images of a debris
disc orbiting a subgiant, but Kappa CrB is a rare example of an intermediate
mass star where a detailed study of the structure of the planetary system can
be made, including both planets and planetesimal belt(s). The only way to
discover planets around such stars using the radial velocity technique is to
observe 'retired' A stars, which are cooler and slower rotators compared to
their main-sequence counterparts. A planetary companion has already been
detected orbiting the subgiant Kappa CrB, with revised parameters of m sin i =
2.1MJ and apl = 2.8AU (Johnson et al. 2008a). We present additional Keck I
HIRES radial velocity measurements that provide evidence for a second planetary
companion, alongside Keck II AO imaging that places an upper limit on the mass
of this companion. Modelling of our Herschel images shows that the dust is
broadly distributed, but cannot distinguish between a single wide belt (from 20
to 220AU) or two narrow dust belts (at around 40 and 165AU). Given the
existence of a second planetary companion beyond approximately 3AU it is
possible that the absence of dust within approximately 20AU is caused by
dynamical depletion, although the observations are not inconsistent with
depletion of these regions by collisional erosion, which occurs at higher rates
closer to the star.


title:
Ultrafast photoinduced enhancement of nonlinear optical response in
  15-atom gold clusters on indium tin oxide conducting film

abstract:
  We show that the third order optical nonlinearity of 15-atom gold clusters is
significantly enhanced when in contact with indium tin oxide (ITO) conducting
film. Open and close aperture z-scan experiments together with non-degenerate
pump-probe differential transmission experiments were done using 80 fs laser
pulses centered at 395 nm and 790 nm on gold clusters encased inside
cyclodextrin cavities. We show that two photon absorption coefficient is
enhanced by an order of magnitude as compared to that when the clusters are on
pristine glass plate. The enhancement for the nonlinear optical refraction
coefficient is ~3 times. The photo-induced excited state absorption using
pump-probe experiments at pump wavelength of 395 nm and probe at 790 nm also
show an enhancement by an order of magnitude. These results attributed to the
excited state energy transfer in the coupled gold cluster-ITO system are
different from the enhancement seen so far in charge donor-acceptor complexes
and nanoparticle-conjugate polymer composites.


title: A rapidly spinning supermassive black hole at the centre of NGC 1365

abstract:
  Broad X-ray emission lines from neutral and partially ionized iron observed
in active galaxies have been interpreted as fluorescence produced by the
reflection of hard X-rays off the inner edge of an accretion disk. In this
model, line broadening and distortion result from rapid rotation and
relativistic effects near the black hole, the line shape being sensitive to its
spin. Alternative models in which the distortions result from absorption by
intervening structures provide an equally good description of the data, and
there has been no general agreement on which is correct. Recent claims that the
black hole (2E6 solar masses) at the centre of the galaxy NGC 1365 is rotating
at close to its maximum possible speed rest on the assumption of relativistic
reflection. Here we report X-ray observations of NGC 1365 that reveal the
relativistic disk features through broadened Fe line emission and an associated
Compton scattering excess of 10-30 keV. Using temporal and spectral analyses,
we disentangle continuum changes due to time-variable absorption from
reflection, which we find arises from a region within 2.5 gravitational radii
of the rapidly spinning black hole. Absorption-dominated models that do not
include relativistic disk reflection can be ruled out both statistically and on
physical grounds.


title: Spitzer observations of the thermal emission from WASP-43b

abstract:
  WASP-43b is one of the closest-orbiting hot Jupiters, with a semimajor axis
of a = 0.01526 +/- 0.00018 AU and a period of only 0.81 days. However, it
orbits one of the coolest stars with a hot Jupiter (Tstar = 4520 +/- 120 K),
giving the planet a modest equilibrium temperature of Teq = 1440 +/- 40 K,
assuming zero Bond albedo and uniform planetary energy redistribution. The
eclipse depths and brightness temperatures from our jointly fit model are
0.347% +/- 0.013% and 1670 +/- 23 K at 3.6 {\mu}m and 0.382% +/- 0.015% and
1514 +/- 25 K at 4.5 {\mu}m. The eclipse timings improved the estimate of the
orbital period, P, by a factor of three (P = 0.81347436 +/- 1.4*10-7 days) and
put an upper limit on the eccentricity (e = 0.010+0.010 -0.007). We use our
Spitzer eclipse depths along with four previously reported ground-based
photometric observations in the near-infrared to constrain the atmospheric
properties of WASP-43b. The data rule out a strong thermal inversion in the
dayside atmosphere of WASP-43b. Model atmospheres with no thermal inversions
and fiducial oxygen-rich compositions are able to explain all the available
data. However, a wide range of metallicities and C/O ratios can explain the
data. The data suggest low day-night energy redistribution in the planet,
consistent with previous studies, with a nominal upper limit of about 35% for
the fraction of energy incident on the dayside that is redistributed to the
nightside.


title: The two-loop sunrise graph with arbitrary masses

abstract:
  We discuss the analytical solution of the two-loop sunrise graph with
arbitrary non-zero masses in two space-time dimensions. The analytical result
is obtained by solving a second-order differential equation. The solution
involves elliptic integrals and in particular the solutions of the
corresponding homogeneous differential equation are given by periods of an
elliptic curve.


title:
A Lyman Break Galaxy in the Epoch of Reionization from HST Grism
  Spectroscopy

abstract:
  We present observations of a luminous galaxy at redshift z=6.573 --- the end
of the reioinization epoch --- which has been spectroscopically confirmed
twice. The first spectroscopic confirmation comes from slitless HST ACS grism
spectra from the PEARS survey (Probing Evolution And Reionization
Spectroscopically), which show a dramatic continuum break in the spectrum at
restframe 1216 A wavelength. The second confirmation is done with Keck +
DEIMOS. The continuum is not clearly detected with ground-based spectra, but
high wavelength resolution enables the Lyman alpha emission line profile to be
determined. We compare the line profile to composite line profiles at redshift
z=4.5. The Lyman alpha line profile shows no signature of a damping wing
attenuation, confirming that the intergalactic gas is ionized at redshift
z=6.57. Spectra of Lyman breaks at yet higher redshifts will be possible using
comparably deep observations with IR-sensitive grisms, even at redshifts where
Lyman alpha is too attenuated by the neutral IGM to be detectable using
traditional spectroscopy from the ground.


title: On Classification of Integrable Davey-Stewartson Type Equations

abstract:
  This paper is devoted to the classification of integrable Davey-Stewartson
type equations. A list of potentially deformable dispersionless systems is
obtained through the requirement that such systems must be generated by a
polynomial dispersionless Lax pair. A perturbative approach based on the method
of hydrodynamic reductions is employed to recover the integrable systems along
with their Lax pairs. Some of the found systems seem to be new.


title:
Integration of nanoscale memristor synapses in neuromorphic computing
  architectures

abstract:
  Conventional neuro-computing architectures and artificial neural networks
have often been developed with no or loose connections to neuroscience. As a
consequence, they have largely ignored key features of biological neural
processing systems, such as their extremely low-power consumption features or
their ability to carry out robust and efficient computation using massively
parallel arrays of limited precision, highly variable, and unreliable
components. Recent developments in nano-technologies are making available
extremely compact and low-power, but also variable and unreliable solid-state
devices that can potentially extend the offerings of availing CMOS
technologies. In particular, memristors are regarded as a promising solution
for modeling key features of biological synapses due to their nanoscale
dimensions, their capacity to store multiple bits of information per element
and the low energy required to write distinct states. In this paper, we first
review the neuro- and neuromorphic-computing approaches that can best exploit
the properties of memristor and-scale devices, and then propose a novel hybrid
memristor-CMOS neuromorphic circuit which represents a radical departure from
conventional neuro-computing approaches, as it uses memristors to directly
emulate the biophysics and temporal dynamics of real synapses. We point out the
differences between the use of memristors in conventional neuro-computing
architectures and the hybrid memristor-CMOS circuit proposed, and argue how
this circuit represents an ideal building block for implementing brain-inspired
probabilistic computing paradigms that are robust to variability and
fault-tolerant by design.


title: Measuring the Size of Large No-Limit Poker Games

abstract:
  In the field of computational game theory, games are often compared in terms
of their size. This can be measured in several ways, including the number of
unique game states, the number of decision points, and the total number of
legal actions over all decision points. These numbers are either known or
estimated for a wide range of classic games such as chess and checkers. In the
stochastic and imperfect information game of poker, these sizes are easily
computed in "limit" games which restrict the players' available actions, but
until now had only been estimated for the more complicated "no-limit" variants.
In this paper, we describe a simple algorithm for quickly computing the size of
two-player no-limit poker games, provide an implementation of this algorithm,
and present for the first time precise counts of the number of game states,
information sets, actions and terminal nodes in the no-limit poker games played
in the Annual Computer Poker Competition.


title:
Interpretation of Quasielastic Scattering Spectra of Probe Species in
  Complex Fluids

abstract:
  The objective of this paper is to correct an error in analyses of
quasielastic scattering spectra. The error invokes a valid calculation under
conditions in which its primary assumptions are incorrect, resulting in
misleading interpretations of spectra. Quasielastic scattering from dilute
probes yields the incoherent structure factor g^(1s)(q,t) = <exp(i q Dx(t))>,
with q being the magnitude of the scattering vector q and Dx(t) being the probe
displacement parallel to q during a time interval t. The error is a claim that
g^(1s)(q,t) ~ exp(- q^2 <(Dx(t))^2> /2) for probes in an arbitrary solution,
leading to the incorrect belief that <(Dx(t))^2 > of probes in complex fluids
can be inferred from quasielastic scattering. The actual theoretical result
refers only to monodisperse probes in simple Newtonian liquids. In general,
g^(1s)(q,t) is determined by all even moments <(Dx(t))^(2n) >, n = 1, 2, 3,...
of the displacement distribution function P(Dx,t). Correspondingly, <(Dx(t))^2
> cannot in general be inferred from g^(1s)(q,t). The theoretical model that
ties g^(1s)(q,t) to <(Dx(t))^2 > also quantitatively determines exactly how
<(Dx(t))^2> /2 must behave, namely <(Dx(t))^2 > must increase linearly with t.
If the spectrum is not a single exponential in time, g^(1s)(q,t) does not
determine <(Dx(t))^2>.


title:
The arbitrage-free Multivariate Mixture Dynamics Model: Consistent
  single-assets and index volatility smiles

abstract:
  We introduce a multivariate diffusion model that is able to price derivative
securities featuring multiple underlying assets. Each asset volatility smile is
modeled according to a density-mixture dynamical model while the same property
holds for the multivariate process of all assets, whose density is a mixture of
multivariate basic densities. This allows to reconcile single name and
index/basket volatility smiles in a consistent framework. Our approach could be
dubbed a multidimensional local volatility approach with vector-state dependent
diffusion matrix. The model is quite tractable, leading to a complete market
and not requiring Fourier techniques for calibration and dependence measures,
contrary to multivariate stochastic volatility models such as Wishart. We prove
existence and uniqueness of solutions for the model stochastic differential
equations, provide formulas for a number of basket options, and analyze the
dependence structure of the model in detail by deriving a number of results on
covariances, its copula function and rank correlation measures and
volatilities-assets correlations. A comparison with sampling simply-correlated
suitably discretized one-dimensional mixture dynamical paths is made, both in
terms of option pricing and of dependence, and first order expansion
relationships between the two models' local covariances are derived. We also
show existence of a multivariate uncertain volatility model of which our
multivariate local volatilities model is a Markovian projection, highlighting
that the projected model is smoother and avoids a number of drawbacks of the
uncertain volatility version. We also show a consistency result where the
Markovian projection of a geometric basket in the multivariate model is a
univariate mixture dynamics model. A few numerical examples on basket and
spread options pricing conclude the paper.


title: Some knots in S^1 x S^2 with lens space surgeries

abstract:
  We propose a classification of knots in S^1 x S^2 that admit a longitudinal
surgery to a lens space. Any lens space obtainable by longitudinal surgery on
some knots in S^1 x S^2 may be obtained from a Berge-Gabai knot in a Heegaard
solid torus of S^1 x S^2, as observed by Rasmussen. We show that there are yet
two other families of knots: those that lie on the fiber of a genus one fibered
knot and the `sporadic' knots. All these knots in S^1 x S^2 are both doubly
primitive and spherical braids.
  This classification arose from generalizing Berge's list of doubly primitive
knots in S^3, though we also examine how one might develop it using Lisca's
embeddings of the intersection lattices of rational homology balls bounded by
lens spaces as a guide. We conjecture that our knots constitute a complete list
of doubly primitive knots in S^1 x S^2 and reduce this conjecture to
classifying the homology classes of knots in lens spaces admitting a
longitudinal S^1 x S^2 surgery.


title:
Confronting Mueller-Navelet jets in NLL BFKL with LHC experiments at 7
  TeV

abstract:
  More than 25 years ago, Mueller Navelet jets were proposed as a decisive test
of BFKL dynamics at hadron colliders. We here study this process at NLL BFKL
accuracy, taking into account NLL corrections to the Green's function and to
the jet vertices. We present detailed predictions for various observables that
can be measured at LHC in ongoing experiments like ATLAS or CMS at sqrt{s}=7
TeV: the cross-section, the azimuthal correlations and the angular distribution
of these jets. For this purpose, we apply realistic kinematical cuts and
binning, and study the dependence of our results with respect to several
parameters. We then compare our results with those that can be obtained in a
fixed order NLO treatment, and propose specific observables which could
actually be used as a probe of BFKL dynamics.


title:
Alzheimer's disease: analysis of a mathematical model incorporating the
  role of prions

abstract:
  We introduce a mathematical model of the in vivo progression of Alzheimer's
disease with focus on the role of prions in memory impairment. Our model
consists of differential equations that describe the dynamic formation of
{\beta}-amyloid plaques based on the concentrations of A{\beta} oligomers, PrPC
proteins, and the A{\beta}-x-PrPC complex, which are hypothesized to be
responsible for synaptic toxicity. We prove the well-posedness of the model and
provided stability results for its unique equilibrium, when the polymerization
rate of {\beta}-amyloid is constant and also when it is described by a power
law.


title: Parallel Peeling Algorithms

abstract:
  The analysis of several algorithms and data structures can be framed as a
peeling process on a random hypergraph: vertices with degree less than k are
removed until there are no vertices of degree less than k left. The remaining
hypergraph is known as the k-core. In this paper, we analyze parallel peeling
processes, where in each round, all vertices of degree less than k are removed.
It is known that, below a specific edge density threshold, the k-core is empty
with high probability. We show that, with high probability, below this
threshold, only (log log n)/log(k-1)(r-1) + O(1) rounds of peeling are needed
to obtain the empty k-core for r-uniform hypergraphs. Interestingly, we show
that above this threshold, Omega(log n) rounds of peeling are required to find
the non-empty k-core. Since most algorithms and data structures aim to peel to
an empty k-core, this asymmetry appears fortunate. We verify the theoretical
results both with simulation and with a parallel implementation using graphics
processing units (GPUs). Our implementation provides insights into how to
structure parallel peeling algorithms for efficiency in practice.


title: The geometry of lightlike surfaces in Minkowski space

abstract:
  We investigate the geometric properties of lightlike surfaces in the
Minkowski space $\R^{2,1}$, using Cartan's method of moving frames to compute a
complete set of local invariants for such surfaces. Using these invariants, we
give a complete local classification of lightlike surfaces of constant type in
$\R^{2,1}$ and construct new examples of such surfaces.


title: Hadronic parity violation in effective field theory

abstract:
  The application of effective field theories to hadronic parity violation in
two- and three-nucleon systems is described. These methods provide several
important advantages over the traditionally used meson-exchange models, e.g.,
model independence and the possibility to reliably estimate theoretical errors.
We focus on the so-called "pionless" theory and describe calculations of
various two- and three-nucleon observables. The role of parity-violating
three-nucleon interactions is also discussed.


title: Modelling the Air Transport with Complex Networks: a short review

abstract:
  Air transport is a key infrastructure of modern societies. In this paper we
review some recent approaches to air transport, which make extensive use of
theory of complex networks. We discuss possible networks that can be defined
for the air transport and we focus our attention to networks of airports
connected by flights. We review several papers investigating the topology of
these networks and their dynamics for time scales ranging from years to
intraday intervals, and consider also the resilience properties of air networks
to extreme events. Finally we discuss the results of some recent papers
investigating the dynamics on air transport network, with emphasis on
passengers traveling in the network and epidemic spreading mediated by air
transport.


title:
Comparison of the Color Glass Condensate to di-hadron correlations in
  proton-proton and proton-nucleus collisions

abstract:
  We perform a detailed comparison of long range rapidity correlations in the
Color Glass Condensate framework to high multiplicity di-hadron data in
proton-proton and proton-lead collisions from the CMS, ALICE and ATLAS
experiments at the LHC. The overall good agreement thus far of the non-trivial
systematics of theory with data is strongly suggestive of gluon saturation and
the presence of subtle quantum interference effects between rapidity separated
gluons. In particular, the yield of pairs collimated in their relative
azimuthal angle $\Delta\phi\sim 0$, is sensitive to the shape of unintegrated
gluon distributions in the hadrons that are renormalization group evolved in
rapidity from the beam rapidities to those of the measured hadrons. We present
estimates for the collimated di-hadron yield expected in central deuteron-gold
collisions at RHIC.


title:
A bigroupoid's topology (or, Topologising the homotopy bigroupoid of a
  space)

abstract:
  The fundamental bigroupoid of a topological space is one way of capturing its
homotopy 2-type. When the space is semilocally 2-connected, one can lift the
construction to a bigroupoid internal to the category of topological spaces, as
Brown and Danesh-Naruie lifted the fundamental groupoid to a topological
groupoid. For locally relatively contractible spaces the resulting topological
bigroupoid is locally trivial in a way analogous to the case of the topologised
fundamental groupoid.


title: Catch-Disperse-Release Readout for Superconducting Qubits

abstract:
  We analyze a single-shot readout for superconducting qubits via the
controlled catch, dispersion, and release of a microwave field. A tunable
coupler is used to decouple the microwave resonator from the transmission line
during the dispersive qubit-resonator interaction, thus circumventing damping
from the Purcell effect. We show that if the qubit frequency tuning is
sufficiently adiabatic, a fast high-fidelity qubit readout is possible, even in
the strongly nonlinear dispersive regime. Interestingly, the Jaynes-Cummings
nonlinearity leads to the quadrature squeezing of the resonator field below the
standard quantum limit, resulting in a significant decrease of the measurement
error.


title: On the Birnbaum Argument for the Strong Likelihood Principle

abstract:
  An essential component of inference based on familiar frequentist notions,
such as $p$-values, significance and confidence levels, is the relevant
sampling distribution. This feature results in violations of a principle known
as the strong likelihood principle (SLP), the focus of this paper. In
particular, if outcomes $\mathbf{x}^*$ and $\mathbf{y}^*$ from experiments
$E_1$ and $E_2$ (both with unknown parameter $\theta$) have different
probability models $f_1(\cdot),f_2(\cdot)$, then even though
$f_1(\mathbf{x}^*;\theta)=cf_2(\mathbf{y}^*;\theta)$ for all $\theta$, outcomes
$\mathbf{x}^*$ and $\mathbf{y}^*$ may have different implications for an
inference about $\theta$. Although such violations stem from considering
outcomes other than the one observed, we argue this does not require us to
consider experiments other than the one performed to produce the data. David
Cox [Ann. Math. Statist. 29 (1958) 357-372] proposes the Weak Conditionality
Principle (WCP) to justify restricting the space of relevant repetitions. The
WCP says that once it is known which $E_i$ produced the measurement, the
assessment should be in terms of the properties of $E_i$. The surprising upshot
of Allan Birnbaum's [J. Amer. Statist. Assoc. 57 (1962) 269-306] argument is
that the SLP appears to follow from applying the WCP in the case of mixtures,
and so uncontroversial a principle as sufficiency (SP). But this would preclude
the use of sampling distributions. The goal of this article is to provide a new
clarification and critique of Birnbaum's argument. Although his argument
purports that [(WCP and SP) entails SLP], we show how data may violate the SLP
while holding both the WCP and SP. Such cases also refute [WCP entails SLP].


title: Foward the theory of Sobolev's mappings on the plane

abstract:
  The paper is devoted to the study of homeomoephisms with finite distortion on
the plane with use of the modulus techniques.


title:
Resonant inelastic X-ray scattering study of intra-band charge
  excitations in hole-doped high-Tc cuprates

abstract:
  We have performed resonant inelastic x-ray scattering (RIXS) near the Cu-K
edge on cuprate superconductors La(2-x)Sr(x)CuO(4), La(2-x)Ba(x)CuO(4),
La(2-x)Sr(x)Cu(1-y)Fe(y)O(4) and Bi(1.76)Pb(0.35)Sr(1.89)CuO(6+d), covering
underdoped to heavily overdoped regime and focusing on charge excitations
inside the charge-transfer gap. RIXS measurements of the 214 systems with Ei =
8.993 keV have revealed that the RIXS intensity at 1 eV energy transfer has a
minimum at (0,0) and maxima at (0.4pi, 0) and $(0, 0.4pi) for all doping points
regardless of the stripe ordered state, suggesting that the corresponding
structure is not directly related to stripe order. Measurements with Ei = 9.003
keV on metallic La(1.7)Sr(0.3)CuO(4) and Bi(1.76)Pb(0.35)Sr(1.89)CuO(6+d)
exhibit a dispersive intra-band excitation below 4 eV, similar to that observed
in the electron-doped Nd(1.85)Ce(0.15)CuO(4). This is the first observation of
a dispersive intra-band excitation in a hole doped system, evidencing that both
electron and hole doped systems have a similar dynamical charge correlation
function.


title:
Level set percolation for random interlacements and the Gaussian free
  field

abstract:
  We consider continuous-time random interlacements on Z^d, d greater or equal
to 3, and investigate the percolation model where a site x of Z^d is occupied
if the total amount of time spent at x by all the trajectories of the
interlacement at level u > 0 exceeds some given non-negative parameter, and
empty otherwise. Thus, the set of occupied sites forms a subset of the
interlacement at level u. We also investigate percolation properties of empty
sites. A recent isomorphism theorem arXiv:1111.4818 of Sznitman enables us to
"translate" some of the relevant questions into the language of level-set
percolation for the Gaussian free field on Z^d, d greater or equal to 3, for
which useful tools have been developed in arXiv:1202.5172. We also gain new
insights of independent interest concerning "two-sided" level-set percolation,
where a site x of Z^d is occupied if and only if the absolute value of the
field variable at that site exceeds a given non-negative level.


title:
Maximizing Acceptance Probability for Active Friending in On-Line Social
  Networks

abstract:
  Friending recommendation has successfully contributed to the explosive growth
of on-line social networks. Most friending recommendation services today aim to
support passive friending, where a user passively selects friending targets
from the recommended candidates. In this paper, we advocate recommendation
support for active friending, where a user actively specifies a friending
target. To the best of our knowledge, a recommendation designed to provide
guidance for a user to systematically approach his friending target, has not
been explored in existing on-line social networking services. To maximize the
probability that the friending target would accept an invitation from the user,
we formulate a new optimization problem, namely, \emph{Acceptance Probability
Maximization (APM)}, and develop a polynomial time algorithm, called
\emph{Selective Invitation with Tree and In-Node Aggregation (SITINA)}, to find
the optimal solution. We implement an active friending service with SITINA in
Facebook to validate our idea. Our user study and experimental results manifest
that SITINA outperforms manual selection and the baseline approach in solution
quality efficiently.


title: Probing the Extended Gaseous Regions of M31 with Quasar Absorption Lines

abstract:
  We present HST-COS spectra of ten quasars located behind M31, selected to
investigate the properties of gas associated with its extended disk and high
velocity clouds (HVCs). The sightlines have impact parameters ranging between
b= 13 kpc and 112 kpc. No absorption is detected in the four sightlines beyond
b=57 kpc. Of the six remaining sightlines, all of which lie at b<32 kpc and
within the N(HI)= 2E18 cm^{-2} boundary of the HI disk of M31, we detect
low-ionization absorption at M31 velocities along four of them (three of which
include MgII absorption). We also detect MgII absorption from an HVC. We find
that along sightlines where both are detected, the velocity location of the
low-ion gas tracks the peak in 21 cm emission. High-ionization absorption is
detected along the three inner sightlines, but not along the three outer
sightlines, for which CIV data exist. As inferred from 21 cm emission line
maps, only one sightline may have a damped Ly-alpha system. This sightline has
b= 17.5 kpc, and we detect both low- and high-ion absorption lines associated
with it.
  The impact parameters through M31 are similar to the impact parameters of
galaxies identified with MgII absorbers at redshifts 0.1<z<1.0 in a 2011 study
by Rao et al. However, the M31 MgII2796 rest equivalent width values are
significantly smaller. In comparison, moderate-to-strong MgII absorption from
Milky Way gas is detected along all ten sightlines. Thus, this study indicates
that M31 does not present itself as an absorbing galaxy which is typical of
higher-redshift galaxies inferred to give rise to moderate-strength quasar
absorption lines. M31 also appears not to possess an extensive large gaseous
cross section, at least not along the direction of its major axis. (Abridged.)


title: Mechanisms of evolution of avalanches in regular graphs

abstract:
  A mapping of avalanches occurring in the zero-temperature random-field Ising
model (zt-RFIM) to life-periods of a population experiencing immigration is
established. Such a mapping allows the microscopic criteria for occurrence of
an infinite avalanche in a q-regular graph to be determined. A key factor for
an avalanche of spin flips to become infinite is that it interacts in an
optimal way with previously flipped spins. Based on these criteria, we explain
why an infinite avalanche can occur in q-regular graphs only for q>3, and
suggest that this criterion might be relevant for other systems. The generating
function techniques developed for branching processes are applied to obtain
analytical expressions for the duration, pulse-shapes and power spectrum of the
avalanches. The results show that only very long avalanches exhibit a
significant degree of universality.


title: Shortest Path versus Multi-Hub Routing in Networks with Uncertain Demand

abstract:
  We study a class of robust network design problems motivated by the need to
scale core networks to meet increasingly dynamic capacity demands. Past work
has focused on designing the network to support all hose matrices (all matrices
not exceeding marginal bounds at the nodes). This model may be too conservative
if additional information on traffic patterns is available. Another extreme is
the fixed demand model, where one designs the network to support peak
point-to-point demands. We introduce a capped hose model to explore a broader
range of traffic matrices which includes the above two as special cases. It is
known that optimal designs for the hose model are always determined by
single-hub routing, and for the fixed- demand model are based on shortest-path
routing. We shed light on the wider space of capped hose matrices in order to
see which traffic models are more shortest path-like as opposed to hub-like. To
address the space in between, we use hierarchical multi-hub routing templates,
a generalization of hub and tree routing. In particular, we show that by adding
peak capacities into the hose model, the single-hub tree-routing template is no
longer cost-effective. This initiates the study of a class of robust network
design (RND) problems restricted to these templates. Our empirical analysis is
based on a heuristic for this new hierarchical RND problem. We also propose
that it is possible to define a routing indicator that accounts for the
strengths of the marginals and peak demands and use this information to choose
the appropriate routing template. We benchmark our approach against other
well-known routing templates, using representative carrier networks and a
variety of different capped hose traffic demands, parameterized by the relative
importance of their marginals as opposed to their point-to-point peak demands.


title: Chi-Square Discriminators for Transiting Planet Detection in Kepler Data

abstract:
  The Kepler spacecraft observes a host of target stars to detect transiting
planets. Requiring a 7.1 sigma detection in twelve quarters of data yields over
100,000 detections, many of which are false alarms. After a second cut is made
on a robust detection statistic, some 50,000 or more targets still remain.
These false alarms waste resources as they propagate through the remainder of
the software pipeline and so a method to discriminate against them is crucial
in maintaining the desired sensitivity to true events. This paper describes a
chi-square test which represents a novel application of the formalism developed
by Allen for false alarm mitigation in searches for gravitational waves. Using
this technique, the false alarm rate can be lowered to ~5%.


title: Quadratic differentials as stability conditions

abstract:
  We prove that moduli spaces of meromorphic quadratic differentials with
simple zeroes on compact Riemann surfaces can be identified with spaces of
stability conditions on a class of CY3 triangulated categories defined using
quivers with potential associated to triangulated surfaces. We relate the
finite-length trajectories of such quadratic differentials to the stable
objects of the corresponding stability condition.


title:
The Full $B \to D^{*} \tau^{-} \bar{\nu_\tau}$ Angular Distribution and
  CP violating Triple Products

abstract:
  We perform a comprehensive study of the impact of new-physics operators with
different Lorentz structures on $\BDstarellnu$ decays, $(\ell = e, \mu, \tau $)
involving the $b \to c l \nu_\ell$ transition. We present the full three angle
and $q^2$ angular distribution with new physics operators with complex
couplings. Various observables are constructed from the angular distribution
with special focus on the CP violating triple product asymmetries which vanish
in the Standard Model without any hadronic complications. Two of the three
triple products are only sensitive to vector/axial vector new physics
operators. %and do not depend on pseudoscalar new physics. Hence, the
measurements of non-zero triple-product asymmetries will be a clear sign of new
physics and a strong signal for vector/axial vector new physics operators. Even
though we focus on $\tau$ final state, one can use the triple-products to
search for new physics with $e$ and $\mu$ in the final state.


title: General black holes, untwisted

abstract:
  We use solution-generating techniques to construct interpolating geometries
between general asymptotically flat, charged, rotating, non-extremal black
holes in four and five dimensions and their subtracted geometries. In the
four-dimensional case, this is achieved by the use of Harrison transformations,
whereas in the five-dimensional case we use STU transformations. We also give
the interpretation of these solution-generating transformations in terms of
string (pseudo)-dualities, showing that they correspond to combinations of
T-dualities and Melvin twists. Upon uplift to one dimension higher, these
dualities allow us to "untwist" general black holes to AdS_3 times a sphere.


title:
MSSM Higgs Boson Searches at the LHC: Benchmark Scenarios after the
  Discovery of a Higgs-like Particle

abstract:
  A Higgs-like particle with a mass of about 125.5 GeV has been discovered at
the LHC. Within the current experimental uncertainties, this new state is
compatible with both the predictions for the Standard Model (SM) Higgs boson
and with the Higgs sector in the Minimal Supersymmetric Standard Model (MSSM).
We propose new low-energy MSSM benchmark scenarios that, over a wide parameter
range, are compatible with the mass and production rates of the observed
signal. These scenarios also exhibit interesting phenomenology for the MSSM
Higgs sector. We propose a slightly updated version of the well-known mh-max
scenario, and a modified scenario (mh-mod), where the light CP-even Higgs boson
can be interpreted as the LHC signal in large parts of the MA-tan \beta\ plane.
Furthermore, we define a light stop scenario that leads to a suppression of the
lightest CP-even Higgs gluon fusion rate, and a light stau scenario with an
enhanced decay rate of h to \gamma\gamma\ at large tan \beta. We also suggest a
\tau-phobic Higgs scenario in which the lightest Higgs can have suppressed
couplings to down-type fermions. We propose to supplement the specified value
of the \mu\ parameter in some of these scenarios with additional values of both
signs. This has a significant impact on the interpretation of searches for the
non SM-like MSSM Higgs bosons. We also discuss the sensitivity of the searches
to heavy Higgs decays into light charginos and neutralinos, and to decays of
the form H to hh. Finally, in addition to all the other scenarios where the
lightest CP-even Higgs is interpreted as the LHC signal, we propose a low-MH
scenario, where instead the heavy CP-even Higgs boson corresponds to the new
state around 125.5 GeV.


title: Geometric quantum discord through the Schatten 1-norm

abstract:
  It has recently been pointed out that the geometric quantum discord, as
defined by the Hilbert-Schmidt norm (2-norm), is not a good measure of quantum
correlations, since it may increase under local reversible operations on the
unmeasured subsystem. Here, we revisit the geometric discord by considering
general Schatten p-norms, explicitly showing that the 1-norm is the only p-norm
able to define a consistent quantum correlation measure. In addition, by
restricting the optimization to the tetrahedron of two-qubit Bell-diagonal
states, we provide an analytical expression for the 1-norm geometric discord,
which turns out to be equivalent to the negativity of quantumness. We
illustrate the measure by analyzing its monotonicity properties.


abstract:
  We prove that Lipschitz inverse shadowing for nonsingular flows is equivalent
to structural stability.


title:
Realizing stock market crashes: stochastic cusp catastrophe model of
  returns under the time-varying volatility

abstract:
  This paper develops a two-step estimation methodology, which allows us to
apply catastrophe theory to stock market returns with time-varying volatility
and model stock market crashes. Utilizing high frequency data, we estimate the
daily realized volatility from the returns in the first step and use stochastic
cusp catastrophe on data normalized by the estimated volatility in the second
step to study possible discontinuities in markets. We support our methodology
by simulations where we also discuss the importance of stochastic noise and
volatility in deterministic cusp catastrophe model. The methodology is
empirically tested on almost 27 years of U.S. stock market evolution covering
several important recessions and crisis periods. Due to the very long sample
period we also develop a rolling estimation approach and we find that while in
the first half of the period stock markets showed marks of bifurcations, in the
second half catastrophe theory was not able to confirm this behavior. Results
suggest that the proposed methodology provides an important shift in
application of catastrophe theory to stock markets.


title: Loop Quantization of Shape Dynamics

abstract:
  Loop Quantum Gravity (LQG) is a promising approach to quantum gravity, in
particular because it is based on a rigorous quantization of the kinematics of
gravity. A difficult and still open problem in the LQG program is the
construction of the physical Hilbert space for pure quantum gravity. This is
due to the complicated nature of the Hamilton constraints. The Shape Dynamics
description of General Relativity (GR) replaces the Hamilton constraints with
spatial Weyl constraints, so the problem of finding the physical Hilbert space
reduces to the problem of quantizing the Weyl constraints. Unfortunately, it
turns out that a loop quantization of Weyl constraints is far from trivial
despite their intuitive physical interpretation. A tentative quantization
proposal and interpretation proposal is given in this contribution.


title: Elliptic Flow Suppression due to Hadron Mass Spectrum

abstract:
  Hadron resonance gas models provide a good description of the equation of
state of quantum chromodynamics determined by lattice QCD calculations at
temperatures $T \sim 100-155$ MeV. In this paper we investigate the effects of
an exponentially increasing hadron mass spectrum (Hagedorn spectrum) on the
azimuthal anisotropy of the rapidly expanding matter formed in
ultrarelativistic heavy ion collisions. If the temperature at which the
conversion from fluid degrees of freedom to hadrons is sufficiently close to
the Hagedorn temperature, the production of Hagedorn resonances suppresses the
differential elliptic flow of all hadron species.


title: Content Based Image Retrieval System Using NOHIS-tree

abstract:
  Content-based image retrieval (CBIR) has been one of the most important
research areas in computer vision. It is a widely used method for searching
images in huge databases. In this paper we present a CBIR system called
NOHIS-Search. The system is based on the indexing technique NOHIS-tree. The two
phases of the system are described and the performance of the system is
illustrated with the image database ImagEval. NOHIS-Search system was compared
to other two CBIR systems; the first that using PDDP indexing algorithm and the
second system is that using the sequential search. Results show that
NOHIS-Search system outperforms the two other systems.


title: On matrix inequalities between the power means: counterexamples

abstract:
  We prove that the known sufficient conditions on the real parameters $(p,q)$
for which the matrix power mean inequality
$((A^p+B^p)/2)^{1/p}\le((A^q+B^q)/2)^{1/q}$ holds for every pair of matrices
$A,B>0$ are indeed best possible. The proof proceeds by constructing $2\times2$
counterexamples. The best possible conditions on $(p,q)$ for which
$\Phi(A^p)^{1/p}\le\Phi(A^q)^{1/q}$ holds for every unital positive linear map
$\Phi$ and $A>0$ are also clarified.


title:
Mechanism behind self-sustained oscillations in direct current glow
  discharges and dusty plasmas

abstract:
  An alternative explanation to the mechanism behind self-sustained
oscillations of ions in direct current (DC) glow discharges is provided. Such
description is distinguished from the one provided by the fluid models, where
oscillations are attributed to the positive feedback mechanism associated with
photoionization of particles and photoemission of electrons from the cathode.
Here, oscillations arise as consequence of interaction between an ion and the
surface charges induced by it at the bounding electrodes. Such mechanism
provides an elegant explanation to why self-sustained oscillations occur only
in the negative resistance region of the voltage-current characteristic curve
in the DC glow discharges. Furthermore, this alternative description provides
an elegant explanation to the formation of plasma fireballs in the laboratory
plasma. It has been found that oscillation frequencies increase with ion's
surface charge density, but at the rate which is significantly slower than it
does with the electric field. The presented mechanism also describes
self-sustained oscillations of ions in dusty plasmas, which demonstrates that
self-sustained oscillations in dusty plasmas and DC glow discharges involve
common physical processes.


title:
Lyman-alpha line and continuum radiative transfer in a clumpy
  interstellar medium

abstract:
  Aims: We aim to study the effects of an inhomogeneous interstellar medium
(ISM) on the strength and the shape of the Lyman alpha (Lya) line in starburst
galaxies. Methods: Using our 3D Monte Carlo Lya radiation transfer code, we
study the radiative transfer of Lya, UV and optical continuum photons in
homogeneous and clumpy shells of neutral hydrogen and dust surrounding a
central source. Our simulations predict the Lya and continuum escape fraction,
the Lya equivalent width EW(Lya), the Lya line profile and their dependence on
the gas geometry and the main input physical parameters. Results: The ISM
clumpiness is found to have a strong impact on the Lya line radiative transfer,
entailing a strong dependence of the emergent features of the Lya line (escape
fraction, EW(Lya)) on the ISM morphology. Although a clumpy and dusty ISM
appears more transparent to radiation (both line and continuum) compared to an
equivalent homogeneous ISM of equal dust optical depth, we find that the Lya
photons are, in general, still more attenuated than UV continuum radiation. As
a consequence, the observed Lya equivalent width (EWobs(Lya)) is lower than the
intrinsic one (EWint(Lya)) for nearly all clumpy ISM configurations considered.
There are, however, special conditions under which Lya photons escape more
easily than the continuum, resulting in an enhanced EWobs(Lya). The requirement
for this to happen is that the ISM is almost static (galactic outflows < 200
km/s), extremely clumpy (with density contrasts >10^7 in HI between clumps and
the interclump medium), and very dusty (E(B-V) > 0.30). When these conditions
are fulfilled the emergent Lya line profile shows no velocity shift and little
asymmetry. Given the asymmetry and velocity shifts generally observed in
starburst galaxies with Lya emission, we conclude that clumping is unlikely to
significantly enhance their relative Lya/UV transmission.


title: Scoup-SMT: Scalable Coupled Sparse Matrix-Tensor Factorization

abstract:
  How can we correlate neural activity in the human brain as it responds to
words, with behavioral data expressed as answers to questions about these same
words? In short, we want to find latent variables, that explain both the brain
activity, as well as the behavioral responses. We show that this is an instance
of the Coupled Matrix-Tensor Factorization (CMTF) problem. We propose
Scoup-SMT, a novel, fast, and parallel algorithm that solves the CMTF problem
and produces a sparse latent low-rank subspace of the data. In our experiments,
we find that Scoup-SMT is 50-100 times faster than a state-of-the-art algorithm
for CMTF, along with a 5 fold increase in sparsity. Moreover, we extend
Scoup-SMT to handle missing data without degradation of performance. We apply
Scoup-SMT to BrainQ, a dataset consisting of a (nouns, brain voxels, human
subjects) tensor and a (nouns, properties) matrix, with coupling along the
nouns dimension. Scoup-SMT is able to find meaningful latent variables, as well
as to predict brain activity with competitive accuracy. Finally, we demonstrate
the generality of Scoup-SMT, by applying it on a Facebook dataset (users,
friends, wall-postings); there, Scoup-SMT spots spammer-like anomalies.


title:
Current Density Impedance Imaging of an Anisotropic Conductivity in a
  Known Conformal Class

abstract:
  We present a procedure for recovering the conformal factor of an anisotropic
conductivity matrix in a known conformal class in a domain in Euclidean space
of dimension greater than or equal to 2. The method requires one internal
measurement, together with a priori knowledge of the conformal class (local
orientation) of the conductivity matrix. This problem arises in the
coupled-physics medical imaging modality of Current Density Impedance Imaging
(CDII) and the assumptions on the data are suitable for measurements
determinable from cross-property based couplings of the two imaging modalities
CDII and Diffusion Tensor Imaging (DTI). We show that the corresponding
electric potential is the unique solution of a constrained minimization problem
with respect to a weighted total variation functional defined in terms of the
physical data. Further, we show that the associated equipotential surfaces are
area minimizing with respect to a Riemannian metric obtained from the data. The
results are also extended to allow the presence of perfectly conducting and/or
insulating inclusions.


title:
Simultaneous exoplanet detection and instrument aberration retrieval in
  multispectral coronagraphic imaging

abstract:
  High-contrast imaging for the detection and characterization of exoplanets
relies on the instrument's capability to block out the light of the host star.
Some current post-processing methods for calibrating out the residual speckles
use information redundancy offered by multispectral imaging but do not use any
prior information on the origin of these speckles. We investigate whether
additional information on the system and image formation process can be used to
more finely exploit the multispectral information. We developed an inversion
method in a Bayesian framework that is based on an analytical imaging model to
estimate both the speckles and the object map. The model links the instrumental
aberrations to the speckle pattern in the image focal plane, distinguishing
between aberrations upstream and downstream of the coronagraph. We propose and
validate several numerical techniques to handle the difficult minimization
problems of phase retrieval and achieve a contrast of 10^6 at 0.2 arcsec from
simulated images, in the presence of photon noise. This opens up the the
possibility of tests on real data where the ultimate performance may override
the current techniques if the instrument has good and stable coronagraphic
imaging quality. This paves the way for new astrophysical exploitations or even
new designs for future instruments.


title: Common Rate Maximization in Two-Layer Cellular Radio Systems

abstract:
  We address the common rate maximization problem in two-layer cellular
networks where high-power and low-power base stations are colocated in the same
geographical area. Interference becomes a serious problem when two or more
layers are considered in the same network. For this purpose, power control in
the downlink needs to be used to limit the interference and to fully exploit
the benefits of additional layer deployments.We present an analytical framework
to the common rate maximization problem both with and without maximum power
constraints and propose a heuristic algorithm. We present simulation results
for the proposed approaches in a two-layer network setup and observe a
significant common rate increase compared to single-layer wireless networks.


title: Nonuniqueness of the C operator in PT-symmetric quantum mechanics

abstract:
  The C operator in PT-symmetric quantum mechanics satisfies a system of three
simultaneous algebraic operator equations, $C^2=1$, $[C,PT]=0$, and $[C,H]=0$.
These equations are difficult to solve exactly, so perturbative methods have
been used in the past to calculate C. The usual approach has been to express
the Hamiltonian as $H=H_0+\epsilon H_1$, and to seek a solution for C in the
form $C=e^Q P$, where $Q=Q(q,p)$ is odd in the momentum p, even in the
coordinate q, and has a perturbation expansion of the form $Q=\epsilon
Q_1+\epsilon^3 Q_3+\epsilon^5 Q_5+\ldots$. [In previous work it has always been
assumed that the coefficients of even powers of $\epsilon$ in this expansion
would be absent because their presence would violate the condition that
$Q(p,q)$ is odd in p.] In an earlier paper it was argued that the C operator is
not unique because the perturbation coefficient $Q_1$ is nonunique. Here, the
nonuniqueness of C is demonstrated at a more fundamental level: It is shown
that the perturbation expansion for Q actually has the more general form
$Q=Q_0+\epsilon Q_1+\epsilon^2 Q_2+\ldots$ in which {\it all} powers and not
just odd powers of $\epsilon$ appear. For the case in which $H_0$ is the
harmonic-oscillator Hamiltonian, $Q_0$ is calculated exactly and in closed form
and it is shown explicitly to be nonunique. The results are verified by using
powerful summation procedures based on analytic continuation. It is also shown
how to calculate the higher coefficients in the perturbation series for Q.


title: Interference-Based Cell Selection in Heterogenous Networks

abstract:
  Heterogeneous cellular networks provide significant improvements in terms of
increased data rates and cell coverage, and offer reduced user rate starvation.
However, there are important problems to be solved. In this paper, we identify
that the cell selection criterion is an important factor determining the user
rates especially in the uplink transmissions and apply cell breathing to
determine the user and base station assignments. We observe that the proposed
interference-based cell selection algorithm provides better load balancing
among the base stations in the system to improve the uplink user rates. We
present the implementation steps in a typical LTE network and demonstrate the
performance improvements through simulations.


title:
The Broad Line Region in NGC 4051: An Inflow Illuminated by a 10^5 K
  Accretion Disk

abstract:
  Adopting a spherically symmetric steady-state ballistic inflow as the
kinematic model for the gas distribution responsible for producing the
H{\alpha} emission line and a central black hole (BH) mass of 1.7 x10^6 M_sun,
determined from prior reverberation mapping, leads to the following dimensions
for the size of the broad line region (BLR) in NGC 4051; an inner radius ~3
lt-days and a lower limit to the outer radius ~ 475 lt-days. Thus, the
previously determined reverberation size for the BLR marks just the inner
radius of a much larger volume of ionized gas. The number of ionizing photons
required to sustain the H{\alpha} emission line luminosity exceeds the number
observed to be available from the central AGN by a factor of 3 - 4. Such a
large ionizing deficit can be reconciled if the BLR is ionized by a 10^5 K
accretion disk that is hidden from direct view by the high opacity of
intervening H gas. A new definition is introduced for the ionization parameter
that acknowledges the fact that H opacity significantly attenuates the flux of
ionizing photons in the large, partially ionized, nebula surrounding the AGN.
Collectively, these results have important implications for BH masses estimated
using reverberation radii and the structure of the BLR inferred from
velocity-delay maps.


title:
Note on Solution Regularity of the Generalized Magnetohydrodynamic
  Equations with Partial Dissipation

abstract:
  In this brief note we study the $n$-dimensional magnetohydrodynamic equations
with hyper-viscosity and zero resistivity. We prove global regularity of
solutions when the hyper-viscosity is sufficiently strong.


title:
Polyploidy and Discontinuous Heredity Effect on Evolutionary
  Multi-Objective Optimization

abstract:
  This paper examines the effect of mimicking discontinuous heredity caused by
carrying more than one chromosome in some living organisms cells in
Evolutionary Multi-Objective Optimization algorithms. In this representation,
the phenotype may not fully reflect the genotype. By doing so we are mimicking
living organisms inheritance mechanism, where traits may be silently carried
for many generations to reappear later. Representations with different number
of chromosomes in each solution vector are tested on different benchmark
problems with high number of decision variables and objectives. A comparison
with Non-Dominated Sorting Genetic Algorithm-II is done on all problems.


title:
Error Field Assessment from Driven Rotation of Stable External Kinks at
  EXTRAP-T2R Reversed Field Pinch

abstract:
  A new non-disruptive error field (EF) assessment technique not restricted to
low density and thus low beta was demonstrated at the EXTRAP-T2R reversed field
pinch. Stable and marginally stable external kink modes of toroidal mode number
n=10 and n=8, respectively, were generated, and their rotation sustained, by
means of rotating magnetic perturbations of the same n. Due to finite EFs, and
in spite of the applied perturbations rotating uniformly and having constant
amplitude, the kink modes were observed to rotate non-uniformly and be
modulated in amplitude. This behavior was used to precisely infer the amplitude
and approximately estimate the toroidal phase of the EF. A subsequent scan
permitted to optimize the toroidal phase. The technique was tested against
deliberately applied as well as intrinsic error fields of n=8 and 10.
Corrections equal and opposite to the estimated error fields were applied. The
efficacy of the error compensation was indicated by the increased discharge
duration and more uniform mode rotation in response to a uniformly rotating
perturbation. The results are in good agreement with theory, and the extension
to lower n, to tearing modes and to tokamaks, including ITER, is discussed.


title: Elliptic Springer Theory

abstract:
  We introduce an elliptic version of the Grothendieck-Springer sheaf and
establish elliptic analogues of the basic results of Springer theory. From a
geometric perspective, our constructions specialize geometric Eisenstein series
to the resolution of degree zero, semistable G-bundles by degree zero B-bundles
over an elliptic curve E. From a representation theory perspective, they
produce a full embedding of representations of the elliptic or double affine
Weyl group into perverse sheaves with nilpotent characteristic variety on the
moduli of G-bundles over E. The resulting objects are principal series examples
of elliptic character sheaves, objects expected to play the role of character
sheaves for loop groups.


title:
Oblique electron-cyclotron-emission radial and phase detector of
  rotating magnetic islands applied to alignment and modulation of
  electron-cyclotron-current-drive for neoclassical tearing mode stabilization

abstract:
  A two channel oblique electron cyclotron emission (ECE) radiometer was
installed on the DIII-D tokamak and interfaced to 4 gyrotrons. Oblique ECE was
used to toroidally and radially localize rotating magnetic islands and so
assist their electron cyclotron current drive (ECCD) stabilization. In
particular, after manipulations operated by the interfacing analogue circuit,
the oblique ECE signals directly modulated the current drive in synch with the
island rotation and in phase with the island O-point, for a more efficient
stabilization. Apart from the different toroidal location, the diagnostic view
is identical to the ECCD launch direction,which greatly simplified the
real-time use of the signals. In fact, a simple toroidal extrapolation was
sufficient to lock the modulation to the O-point phase. This was accomplished
by a specially designed phase shifter of nearly flat response over the 1-7kHz
range. Moreover, correlation analysis of two channels slightly above and below
the ECCD frequency allowed checking the radial alignment to the island, based
on the fact that for satisfactory alignment the two signals are out of phase.


title: A variation on Heawood list-coloring for graphs on surfaces

abstract:
  We prove a variation on Heawood list-coloring for graphs on surfaces, modeled
on Thomassen's planar 5-list-coloring theorem. For epsilon>0 define the Heawood
number to be H(epsilon)=Floor((7+Sqrt[24*epsilon+1])/2). We prove that, except
for epsilon=3, every graph embedded on a surface of Euler genus epsilon>0 with
a distinguished face F can be list-colored when the vertices of F have
(H(epsilon)-2)-lists and all other vertices have H(epsilon)-lists unless the
induced subgraph on the vertices of F contains the complete graph on
H(epsilon)-1 vertices.


title: KSU KDD: Word Sense Induction by Clustering in Topic Space

abstract:
  We describe our language-independent unsupervised word sense induction
system. This system only uses topic features to cluster different word senses
in their global context topic space. Using unlabeled data, this system trains a
latent Dirichlet allocation (LDA) topic model then uses it to infer the topics
distribution of the test instances. By clustering these topics distributions in
their topic space we cluster them into different senses. Our hypothesis is that
closeness in topic space reflects similarity between different word senses.
This system participated in SemEval-2 word sense induction and disambiguation
task and achieved the second highest V-measure score among all other systems.


title:
A new integrable problem with a quartic integral in the dynamics of a
  rigid body

abstract:
  We consider the problem of motion of a rigid body about a fixed point under
the action of an axisymmetric combination of potential and gyroscopic forces.
We introduce a new integrable case, valid on zero level of the cyclic integral,
that generalizes the known case of motion of a body in liquid due to Chaplygin
and its subsequent generalization by Yehia. Apart from certain singular
potential terms, the new case involves finite potential and gyroscopic forces,
which admit physical interpretation as resulting from interaction of mass,
magnetized parts and electric charges on the body with gravitational, electric
and magnetic fields.


title:
Reverse Chromatic Aberration and its Numerical Optimization in a
  Metamaterial Lens

abstract:
  In planar metamaterial lenses, the focal point moves with the frequency. Here
it is shown numerically that this movement can be controlled by properly
engineering the dimensions of the metamaterial-based phase shifters that
constitute the lens. In particular, such lenses can be designed to exhibit
unusual chromatic aberration with the focal length increasing, rather than
decreasing, with the frequency. It is proposed that such an artificial
"reverse" chromatic aberration may optimize the transverse resolution of
millimeter wave diagnostics of plasmas and be useful in compensating for the
natural "ordinary" chromatic aberration of other components in an optical
system. More generally, optimized chromatic aberration will allow to
simultaneously focus on several objects located at different distances and
emitting or reflecting at different frequencies.


title: Multi-pole multi-zero frequency-independent phase-shifter

abstract:
  A multi-pole, multi-zero design allowed realizing a "true" phase-shifter (not
time-delayer) of flat frequency-response over more than 3 decades
(30Hz-100kHz), which can be extended to higher frequencies or broader bands
thanks to a modular design. Frequency-dependent optimization of a single
resistance made also the gain flat to within few percents. The
frequency-independent phase-shifter presented can find application in any
experiment in which an action needs to be taken (e.g. a measurement needs to be
performed) at a fixed phase-delay relative to an event, regardless of how
rapidly the system rotates or oscillates.


title: Efficient graph state generation and artificial error detection

abstract:
  How to generate photonic cluster state or graph state efficiently is the main
problem in optical measurement-based quantum computation. Assisted by the cross
phase modulation technique, we propose an efficient scheme to realize the
cascade CZ operation, which could be used to generate universal cluster state,
with the controlled-path gate as element operation. Especially, for the wheel
cluster state, the generation processes are obviously simpler than the former
approaches. Moreover, we consider the artificial error that one forgot to
operate one or some single photons during the generation processes cross-type,
star-type graph state. This error likely occurs in the large scale of graph
state generation with one-by-one pattern and is firstly considered in this
paper. With the present approach, it is possible to judge whether all the
involved single photons are connected as desired or not, i.e., detect the
artificial error with the success probability 1/2.


title:
Existence of strong solutions to the steady Navier-Stokes equations for
  a compressible heat-conductive fluid with large forces

abstract:
  We prove that there exists a strong solution to the Dirichlet boundary value
problem for the steady Navier-Stokes equations of a compressible
heat-conductive fluid with large external forces in a bounded domain $R^d (d =
2, 3)$, provided that the Mach number is appropriately small. At the same time,
the low Mach number limit is rigorously verified. The basic idea in the proof
is to split the equations into two parts, one of which is similar to the steady
incompressible Navier-Stokes equations with large forces, while another part
corresponds to the steady compressible heat-conductive Navier-Stokes equations
with small forces. The existence is then established by dealing with these two
parts separately, establishing uniform in the Mach number a priori estimates
and exploiting the known results on the steady incompressible Navier-Stokes
equations.


title:
Interior regularity of fully nonlinear degenerate elliptic equations, I:
  Bellman equations with constant coefficients

abstract:
  This is the first of a series of papers on the interior regularity of fully
nonlinear degenerate elliptic equations. We consider a stochastic optimal
control problem in which the diffusion coefficients, drift coefficients and
discount factor are independent of the spacial variables. Under suitable
assumptions, for $k=0,1$, when the terminal and running payoffs are globally
$C^{k,1}$, we obtain the $C^{k,1}$-smoothness of the value function, which
yields the existence and uniqueness of the solution to the associated Dirichlet
problem for the degenerate Bellman equation.


title:
On the physical properties of memristive, memcapacitive, and
  meminductive systems

abstract:
  We discuss the physical properties of realistic memristive, memcapacitive and
meminductive systems. In particular, by employing the well-known theory of
response functions and microscopic derivations, we show that resistors,
capacitors and inductors with memory emerge naturally in the response of
systems - especially those of nanoscale dimensions - subjected to external
perturbations. As a consequence, since memristances, memcapacitances, and
meminductances are simply response functions, they are not necessarily finite.
This means that, unlike what has always been argued in some literature,
diverging and non-crossing input-output curves of all these memory elements are
physically possible in both quantum and classical regimes. For similar reasons,
it is not surprising to find memcapacitances and meminductances that acquire
negative values at certain times during dynamics, while the passivity criterion
of memristive systems imposes always a non-negative value on the resistance at
any given time. We finally show that ideal memristors, namely those whose state
depends only on the charge that flows through them (or on the history of the
voltage) are subject to very strict physical conditions and are unable to
protect their memory state against the unavoidable fluctuations, and therefore
are susceptible to a stochastic catastrophe. Similar considerations apply to
ideal memcapacitors and meminductors.


title:
On the Hausdorff dimension of countable intersections of certain sets of
  normal numbers

abstract:
  We show that the set of numbers that are $Q$-distribution normal but not
simply $Q$-ratio normal has full Hausdorff dimension. It is further shown under
some conditions that countable intersections of sets of this form still have
full Hausdorff dimension even though they are not winning sets (in the sense of
W. Schmidt). As a consequence of this, we construct many explicit examples of
numbers that are simultaneously distribution normal but not simply ratio normal
with respect to certain countable families of basic sequences. Additionally, we
prove that some related sets are either winning sets or sets of the first
category.


title:
Efficient and flexible generation of entangled qudits with cross phase
  modulation

abstract:
  In this paper, we provide a simple but powerful module to generate entangled
qudits. This module assisted with cross-Kerr nonlinearity is available to the
entangled qudits generation with arbitrary dimension, and it could work well
even when the two independent qudits lose the same number of single photons.
Moreover, with the cascade uses of modules, the deterministic generation but
with nonidentical forms of entangled qudits is possible.


title: Integral mean estimates for the polar derivative of a polynomial

abstract:
  Let $ P(z) $ be a polynomial of degree $ n $ having all zeros in $|z|\leq k$
where $k\leq 1,$ then it was proved by Dewan \textit{et al} that for every real
or complex number $\alpha$ with $|\alpha|\geq k$ and each $r\geq 0$
  $$
n(|\alpha|-k)\left\{\int\limits_{0}^{2\pi}\left|P\left(e^{i\theta}\right)\right|^r
d\theta\right\}^{\frac{1}{r}}\leq\left\{\int\limits_{0}^{2\pi}\left|1+ke^{i\theta}\right|^r
d\theta\right\}^{\frac{1}{r}}\underset{|z|=1}{Max}|D_\alpha P(z)|. $$
  \indent In this paper, we shall present a refinement and generalization of
above result and also extend it to the class of polynomials
$P(z)=a_nz^n+\sum_{\nu=\mu}^{n}a_{n-\nu}z^{n-\nu},$ $1\leq\mu\leq n,$ having
all its zeros in $|z|\leq k$ where $k\leq 1$ and thereby obtain certain
generalizations of above and many other known results.


title: The progenitor of SN 2011ja: Clues from circumstellar interaction

abstract:
  Massive stars, possibly red supergiants, which retain extended hydrogen
envelopes until core collapse, produce Type II Plateau (IIP) supernovae. The
ejecta from these explosions shock the circumstellar matter originating from
the mass loss of the progenitor during the final phases of its life. This
interaction accelerates particles to relativistic energies which then lose
energy via synchrotron radiation in the shock-amplified magnetic fields and
inverse Compton scattering against optical photons from the supernova. These
processes produce different signatures in the radio and X-ray part of the
electromagnetic spectrum. Observed together, they allow us to break the
degeneracy between shock acceleration and magnetic field amplification. In this
work we use X-rays observations from the Chandra and radio observations from
the ATCA to study the relative importance of processes which accelerate
particles and those which amplify magnetic fields in producing the non-thermal
radiation from SN 2011ja. We use radio observations to constrain the explosion
date. Multiple Chandra observations allow us to probe the history of variable
mass loss from the progenitor. The ejecta expands into a low density bubble
followed by interaction with a higher density wind from a red supergiant
consistent with ZAMS mass greater than 16 solar masses. Our results suggest
that a fraction of type IIP supernovae may interact with circumstellar media
set up by non-steady winds.


title:
Heralded generation of symmetric and asymmetric entangled qudits with
  weak cross-Kerr nonlinearity

abstract:
  High dimensional entangled states have attracted much more attentions, due to
their strong nonlocality and much powerful capability for quantum information
processing. By the methods presented in this paper, arbitrary forms entangled
qudits including symmetric and asymmetric forms could be generated with the
weak cross-Kerr nonlinearity. These schemes are heralded by the detections of
single-photon detectors. If all the detectors do not register any single
photons, the generation is success with the probability $1/n^{M}$ determined by
dimension $n$ and partite $M$. Furthermore, these schemes work well even with
the common photon number nonresolving detectors, therefore they are feasible
with the current experimental technology.


title: Learning Theory in the Arithmetic Hierarchy

abstract:
  We consider the arithmetic complexity of index sets of uniformly computably
enumerable families learnable under different learning criteria. We determine
the exact complexity of these sets for the standard notions of finite learning,
learning in the limit, behaviorally correct learning and anomalous learning in
the limit. In proving the $\Sigma_5^0$-completeness result for behaviorally
correct learning we prove a result of independent interest; if a uniformly
computably enumerable family is not learnable, then for any computable learner
there is a $\Delta_2^0$ enumeration witnessing failure.


title: Sound localization using compressive sensing

abstract:
  In a sensor network with remote sensor devices, it is important to have a
method that can accurately localize a sound event with a small amount of data
transmitted from the sensors. In this paper, we propose a novel method for
localization of a sound source using compressive sensing. Instead of sampling a
large amount of data at the Nyquist sampling rate in time domain, the acoustic
sensors take compressive measurements integrated in time. The compressive
measurements can be used to accurately compute the location of a sound source.


title:
Generalized Multiscale Finite Element Method. Symmetric Interior Penalty
  Coupling

abstract:
  Motivated by applications to numerical simulation of flows in highly
heterogeneous porous media, we develop multiscale finite element methods for
second order elliptic equations. We discuss a multiscale model reduction
technique in the framework of the discontinuous Galerkin finite element method.
We propose three different finite element spaces on the coarse mesh.
  The first space is based on a local eigenvalue problem that uses a weighted
$L_2-$norm for computing the "mass" matrix. The second space is generated by
amending the eigenvalue problem of the first case with a term related to the
penalty. The third choice is based on generation of a large space of snapshots
and subsequent selection of a subspace of a reduced dimension.
  The approximation with these spaces is based on the discontinuous Galerkin
finite element method framework. We investigate the stability and derive error
estimates for the methods and further experimentally study their performance on
a representative number of numerical examples.


title:
Exactly Soluble Model of a 3D Symmetry Protected Topological Phase of
  Bosons with Surface Topological Order

abstract:
  We construct an exactly soluble Hamiltonian on the D=3 cubic lattice, whose
ground state is a topological phase of bosons protected by time reversal
symmetry, i.e a symmetry protected topological (SPT) phase. In this model
anyonic excitations are shown to exist at the surface but not in the bulk. The
statistics of these surface anyons is explicitly computed and shown to be
identical to the 3-fermion Z2 model, a variant of Z2 topological order which
cannot be realized in a purely D=2 system with time reversal symmetry. Thus the
model realizes a novel surface termination for SPT phases, which only becomes
available in D=3: that of a fully symmetric gapped surface with topological
order. The 3D phase found here is also outside the group cohomology
classification that appears to capture all SPT phases in lower dimensions. It
is identified with a phase previously predicted from a field theoretic
analysis, whose surface is roughly `half' of a Kitaev E8 phase. Our
construction utilizes the Walker-Wang prescription to create a 3D confined
phase with surface anyons,which can be extended to other symmetry classes and
topological orders.


title:
Interplay between superconductivity and pseudogap state in bilayer
  cuprate superconductors

abstract:
  The interplay between the superconducting gap and normal-state pseudogap in
the bilayer cuprate superconductors is studied based on the kinetic energy
driven superconducting mechanism. It is shown that the charge carrier
interaction directly from the interlayer coherent hopping in the kinetic energy
by exchanging spin excitations does not provide the contribution to the
normal-state pseudogap in the particle-hole channel and superconducting gap in
the particle-particle channel, while only the charge carrier interaction
directly from the intralayer hopping in the kinetic energy by exchanging spin
excitations induces the normal-state pseudogap in the particle-hole channel and
superconducting gap in the particle-particle channel, and then the two-gap
behavior is a universal feature for the single layer and bilayer cuprate
superconductors.


title: A null space property approach to compressed sensing with frames

abstract:
  An interesting topic in compressive sensing concerns problems of sensing and
recovering signals with sparse representations in a dictionary. In this note,
we study conditions of sensing matrices A for the L1-synthesis method to
accurately recover sparse, or nearly sparse signals in a given dictionary D. In
particular, we propose a dictionary based null space property (D-NSP) which, to
the best of our knowledge, is the first sufficient and necessary condition for
the success of the L1 recovery. This new property is then utilized to detect
some of those dictionaries whose sparse families cannot be compressed
universally. Moreover, when the dictionary is full spark, we show that AD being
NSP, which is well-known to be only sufficient for stable recovery via
L1-synthesis method, is indeed necessary as well.


title:
Analyzing Machupo virus-receptor binding by molecular dynamics
  simulations

abstract:
  In many biological applications, we would like to be able to computationally
predict mutational effects on affinity in protein-protein interactions.
However, many commonly used methods to predict these effects perform poorly in
important test cases. In particular, the effects of multiple mutations,
non-alanine substitutions, and flexible loops are difficult to predict with
available tools and protocols. We present here an existing method applied in a
novel way to a new test case; we interrogate affinity differences resulting
from mutations in a host-virus protein-protein interface. We use steered
molecular dynamics (SMD) to computationally pull the machupo virus (MACV) spike
glycoprotein (GP1) away from the human transferrin receptor (hTfR1). We then
approximate affinity using the maximum applied force of separation and the area
under the force-versus-distance curve. We find, even without the rigor and
planning required for free energy calculations, that these quantities can
provide novel biophysical insight into the GP1/hTfR1 interaction. First, with
no prior knowledge of the system we can differentiate among wild type and
mutant complexes. Moreover, we show that this simple SMD scheme correlates well
with relative free energy differences computed via free energy perturbation.
Second, although the static co-crystal structure shows two large
hydrogen-bonding networks in the GP1/hTfR1 interface, our simulations indicate
that one of them may not be important for tight binding. Third, one viral site
known to be critical for infection may mark an important evolutionary
suppressor site for infection-resistant hTfR1 mutants. Finally, our approach
provides a framework to compare the effects of multiple mutations, individually
and jointly, on protein-protein interactions.


title:
Combinatorial characterizations of the Cohen-Macaulayness of the second
  power of edge ideals

abstract:
  Let $I(G)$ be the edge ideal of a simple graph $G$. In this paper, we will
give sufficient and necessary combinatorial conditions of $G$ in which the
second symbolic and ordinary power of its edge ideal are Cohen-Macaulay (resp.
Buchsbaum, generalized Cohen-Macaulay).
  As an application of our results, we will classify all bipartite graphs in
which the second (symbolic) powers are Cohen-Macaulay (resp. Buchsbaum,
generalized Cohen-Macaulay).


title:
Interior regularity of fully nonlinear degenerate elliptic equations,
  II: real and complex Monge-Amp\`ere equations

abstract:
  We first obtain the interior $C^{1,1}$-regularity and solvability for the
degenerate real Monge-Amp\`ere equation in a bounded, $C^3$-smooth and strictly
convex domain in $\mathbb R^d$ ($d\ge2$), assuming that the boundary data is
only globally $C^{1,1}$, and the $d$-th root of the nonnegative right-hand side
is globally $C^{0,1}$ and convex after adding $K|x|^2$ for some constant $K$.
Then we establish the interior $C^{1,1}$-regularity and solvability for the
degenerate complex Monge-Amp\`ere equation in a bounded, $C^3$-smooth and
strictly pseudoconvex domain in $\mathbb C^d$, under the global
$C^{1,1}$-regularity assumption on the boundary data and the $d$-th root of the
nonnegative right-hand side. Since the derivatives may blow up along
non-tangent directions at the boundary under our regularity assumptions on the
boundary data, we also estimate the derivatives up to second order in both
problems. Our technique is probabilistic by following Krylov's approach.
  The result in the real case extends N. Trudinger and J. Urbas's interior
$C^{1,1}$-regularity result for the homogeneous case [N. Trudinger and J.
Urbas, Bull. Austral. Math. Soc., 30(3): 321~334, 1984.] in the sense of
considering the nonnegative right-hand side. The result in the complex case
generalizes E. Bedford and B. A. Taylor's interior $C^{1,1}$-regularity result
in a ball [E. Bedford and B. A. Taylor, Invent. Math., 37(1): 1~44, 1976.] by
allowing the domain be any bounded, sufficiently smooth and strictly
pseudoconvex one.


title: Isocurvature Constraints and Gravitational Ward Identity

abstract:
  Axions and WIMPZILLAs are well-motivated dark matter candidates with
interesting cos- mological implications, such as isocurvature perturbations and
non-Gaussianities. How- ever, these predicted implications in the literature
are based on the assumption that the cross-correlation between curvature and
CDM isocurvature is negligible. This contribution discusses the
cross-correlation in the axion and the WIMPZILLA scenarios. Particularly, it is
shown that the gravitational Ward identity associated with diffeomorphism
invariance plays an important role in this cross-correlation calculation
confirming the assumption.


title: Compact embedding in the space of piecewise H1 functions

abstract:
  We prove a compact embedding theorem in a class of spaces of piecewise H1
functions subordinated to a class of shape regular, but not necessarily
quasi-uniform triangulations of a polygonal domain. This result generalizes the
Rellich--Kondrachov theorem. It is used to prove generalizations to piecewise
functions of nonstandard Poincar\'e--Friedrichs inequalities. It can be used to
prove Korn inequalities for piecewise functions associated with elastic shells.


title:
Parameter Identification of Induction Motor Using Modified Particle
  Swarm Optimization Algorithm

abstract:
  This paper presents a new technique for induction motor parameter
identification. The proposed technique is based on a simple startup test using
a standard V/F inverter. The recorded startup currents are compared to that
obtained by simulation of an induction motor model. A Modified PSO optimization
is used to find out the best model parameter that minimizes the sum square
error between the measured and the simulated currents. The performance of the
modified PSO is compared with other optimization methods including line search,
conventional PSO and Genetic Algorithms. Simulation results demonstrate the
ability of the proposed technique to capture the true values of the machine
parameters and the superiority of the results obtained using the modified PSO
over other optimization techniques.


title: Review of intelligent tutoring systems using bayesian approach

abstract:
  With advancement in computer science research on artificial intelligence and
in cognitive psychology research on human learning and performance, the next
generation of computer-based tutoring systems moved beyond the simple
presentation of pages of text or graphics. These new intelligent tutoring
systems (ITSs) called cognitive tutors; incorporated model-tracing technology
which is a cognitive model of student problem solving that captures students
multiple strategies and common misconceptions. Such Intelligent tutoring
systems or Knowledge Based Tutoring Systems can guide learners to progress in
the learning process at their best. This paper deals with the review of various
Intelligent tutoring systems using Bayesian Networks and how Bayesian Networks
can be used for efficient decision making.


title:
K Means Segmentation of Alzheimers Disease in PET scan datasets: An
  implementation

abstract:
  The Positron Emission Tomography (PET) scan image requires expertise in the
segmentation where clustering algorithm plays an important role in the
automation process. The algorithm optimization is concluded based on the
performance, quality and number of clusters extracted. This paper is proposed
to study the commonly used K Means clustering algorithm and to discuss a brief
list of toolboxes for reproducing and extending works presented in medical
image analysis. This work is compiled using AForge .NET framework in windows
environment and MATrix LABoratory (MATLAB 7.0.1)