title: Deconstructing Queue-Based Mutual Exclusion

abstract:
  We formulate a modular approach to the design and analysis of a particular
class of mutual exclusion algorithms for shared memory multiprocessor systems.
Specifically, we consider algorithms that organize waiting processes into a
queue. Such algorithms can achieve O(1) remote memory reference (RMR)
complexity, which minimizes (asymptotically) the amount of traffic through the
processor-memory interconnect. We first describe a generic mutual exclusion
algorithm that relies on a linearizable implementation of a particular
queue-like data structure that we call MutexQueue. Next, we show two
implementations of MutexQueue using O(1) RMRs per operation based on
synchronization primitives commonly available in multiprocessors. These
implementations follow closely the queuing code embedded in previously
published mutual exclusion algorithms. We provide rigorous correctness proofs
and RMR complexity analyses of the algorithms we present.


title:
Probing the structure of local magnetic field of solar features with
  helioseismology

abstract:
  Motivated by the problem of local solar subsurface magnetic structure, we
have used numerical simulation to investigate the propagation of waves through
monolithic magnetic flux tubes of different size. A cluster model can be a good
approximation to simulate sunspots as well as solar plage regions which are
composed of an ensemble of compactly packed thin flux tubes. Simulations of
this type is a powerful tool to probe the structure and the dynamic of various
solar features which are related directly to solar magnetic field activity.


title:
Continuous and discrete Schrodinger systems with PT-symmetric
  nonlinearities

abstract:
  We investigate the dynamical behavior of continuous and discrete Schrodinger
systems exhibiting parity-time (PT) invariant nonlinearities. We show that such
equations behave in a fundamentally different fashion than their nonlinear
Schrodinger counterparts. In particular, the PT-symmetric nonlinear Schrodinger
equation can simultaneously support both bright and dark soliton solutions. In
addition, we study a two-element discretized version of this PT nonlinear
Schr\"odinger equation. By obtaining the underlying invariants, we show that
this system is fully integrable and we identify the PT-symmetry breaking
conditions. This arrangement is unique in the sense that the exceptional points
are fully dictated by the nonlinearity itself.


title: Antinematic local order in dendrimer liquids

abstract:
  We use monomer-resolved numerical simulations to study the positional and
orientational structure of a dense dendrimer solution, focusing on the effects
of dendrimers' prolate shape and deformability on the short-range order. Our
results provide unambiguous evidence that the nearest-neighbor shell of a
tagged particle consists of a mixture of crossed, side-by-side, side-to-end,
and end-to-end pair configurations, imposing antinematic rather than nematic
order observed in undeformable rodlike particles. This packing pattern persists
even at densities where particle overlap becomes sizable. We demonstrate that
the antinematic arrangement is compatible with the A15 crystal lattice reported
in several dendrimer compounds.


title:
On the hitting times of continuous-state branching processes with
  immigration

abstract:
  We study the two-dimensional joint distribution of the first hitting time of
a constant level by a continuous-state branching process with immigration and
their primitive stopped at this time. We show an explicit expression of its
Laplace transform. Using this formula, we study the polarity of zero and
provide a necessary and sufficient criterion for transience or recurrence. We
follow the approach of Shiga, T. (1990) [A recurrence criterion for Markov
processes of Ornstein-Uhlenbeck type. Probability Theory and Related Fields,
85(4), 425-447], by finding some $\lambda$-invariant functions for the
generator.


title: How do birth and death processes come down from infinity?

abstract:
  We finely describe the "coming down from infinity" for birth and death
processes which eventually become extinct. Our biological motivation is to
study the decrease of regulated populations which are initially large. Under
general assumptions on the birth and death rates, we describe the behavior of
the hitting time of large integers. We let two regimes appear and derive an
expression of the speed of coming down from infinity. In the case of death
rates with regular variations, we also get a central limit theorem and the
asymptotic probability of extinction in small times. Finally, we apply our
results to birth and death processes in varying environment in whose the
environment influences the competition.


title:
Maximum uniformly resolvable decompositions of $K_v$ and $K_v - I$ into
  3-stars and 3-cycles

abstract:
  Let $K_v$ denote the complete graph of order $v$ and $K_v - I$ denote $K_v$
minus a 1-factor. In this article we investigate uniformly resolvable
decompositions of $K_v$ and $K_v-I$ into $r$ classes containing only copies of
$3$-stars and $s$ classes containing only copies of $3$-cycles. We completely
determine the spectrum in the case where the number of resolution classes of
3-stars is maximum.


title: Well-posedness of first order semilinear PDEs by stochastic perturbation

abstract:
  We show that first order semilinear PDEs by stochastic perturbation are
well-posedness for globally Holder continuous and bounded vector field, with an
integrability condition on the divergence. This result extends the liner case
presented in [2]. The proof is based on in the stochastic characteristics
method and a version of the commuting Lemma.


title:
Electronic transport properties of topological insulator films and low
  dimensional superconductors

abstract:
  In this review, we present a summary of some recent experiments on
topological insulators (TIs) and superconducting nanowires and films.
Electron-electron interaction (EEI), weak anti-localization (WAL) and
anisotropic magneto-resistance (AMR) effect found in TI films by transport
measurements are reported. Then, transport properties of superconducting films,
bridges and nanowires and proximity effect in non-superconducting nanowires are
described. Finally, the interplay between TIs and superconductors (SCs) is also
discussed.


title:
Composite profile of the Fe K$\alpha$ spectral line emitted from a
  binary system of supermassive black holes

abstract:
  We used a model of a relativistic accretion disk around a supermassive black
hole (SMBH), based on ray-tracing method in the Kerr metric, to study the
variations of the composite Fe K$\alpha$ line emitted from two accretion disks
around SMBHs in a binary system. We assumed that the orbit of such a binary is
approximately Keplerian, and simulated the composite line shapes for different
orbital elements, accretion disk parameters and mass ratios of the components.
The obtained results show that, if observed in the spectra of some SMBH
binaries during their different orbital phases, such composite Fe K$\alpha$
line profiles could be used to constrain the orbits and several properties of
such SMBH binaries.


title: Cosimplicial C-infinity rings and the de Rham complex of Euclidean space

abstract:
  A C-infinity ring is a set equipped with n-ary operations corresponding to
smooth n-ary functions on the real line (satisfying natural axioms). We prove
that the cosimplicial abelian group associated to the de Rham complex of
Euclidean space has the structure of a cosimplicial C-infinity ring. We also
analyse the notion of R-module (following Quillen) for a (co-)simplicial
C-infinity ring R.


title: Reconstruction of physics objects in the CMS detector

abstract:
  The reconstruction and identification of physics objects in the CMS detector,
in the context of the charged Higgs boson search analysis, are presented. The
reconstruction algorithms and their performance in 7 TeV and 8 TeV LHC data are
discussed. The identification of tau hadronic decays, the reconstruction of
hadronic jets and missing transverse energy and the identification of b jets
are described in detail.


title: Average Case Analysis of Java 7's Dual Pivot Quicksort

abstract:
  Recently, a new Quicksort variant due to Yaroslavskiy was chosen as standard
sorting method for Oracle's Java 7 runtime library. The decision for the change
was based on empirical studies showing that on average, the new algorithm is
faster than the formerly used classic Quicksort. Surprisingly, the improvement
was achieved by using a dual pivot approach, an idea that was considered not
promising by several theoretical studies in the past. In this paper, we
identify the reason for this unexpected success. Moreover, we present the first
precise average case analysis of the new algorithm showing e.g. that a random
permutation of length $n$ is sorted using $1.9n\ln n-2.46n+\mathcal{O}(\ln n)$
key comparisons and $0.6n\ln n+0.08n+\mathcal{O}(\ln n)$ swaps.


title: Self-healing of unitarity in Higgs inflation

abstract:
  We reconsider perturbative unitarity violation in the standard model Higgs
inflation model. We show that the Cutkosky cutting rule implied by perturbative
unitarity is fulfilled at one-loop. This is a strong indication that unitarity
is restored order by order in perturbation theory. We then resum certain
one-loop diagrams and show that the relevant dressed amplitude fulfills the
Cutkosky rule exactly. This is an example of the self-healing mechanism. The
original Higgs inflation model is thus consistent and does not require any new
physics beyond the standard model at least up to the Planck scale.


title: Hole doped Dirac states in silicene by biaxial tensile strain

abstract:
  The effects of biaxial tensile strain on the structure, electronic states,
and mechanical properties of silicene are studied by ab-initio calculations.
Our results show that up to 5% strain the Dirac cone remains essentially at the
Fermi level, while higher strain induces hole doping because of weakening of
the Si$-$Si bonds. We demonstrate that the silicene lattice is stable up to 17%
strain. It is noted that the buckling first decreases with the strain (up to
10%) and then increases again, which is accompanied by a band gap variation. We
also calculate the Gr\"uneisen parameter and demonstrate a strain dependence
similar to that of graphene.


title: Complex Langevin simulation for QCD-like models

abstract:
  We first test the Complex Langevin method (CLE) on various simple models. We
then introduce the method of Gauge Cooling to control the dynamics of the
process and ensure thin distributions in the imaginary direction. We finally
apply CLE with gauge cooling to a QCD-related lattice model (HQCD) and compare
the results by CLE and by a refined Reweighting method (rRW). Very good
agreement is found in all regions of physical interest.


title:
The d-p band-inversion topological insulator in bismuth-based
  skutterudites

abstract:
  Skutterudites, a class of materials with cage-like crystal structure which
have received considerable research interest in recent years, are the breeding
ground of several unusual phenomena such as heavy fermion superconductivity,
exciton-mediated superconducting state and Weyl fermions. Here, we predict a
new topological insulator in bismuth-based skutterudites, in which the bands
involved in the topological band-inversion process are d- and p-orbitals, which
is distinctive with usual topological insulators, for instance in Bi2Se3 and
BiTeI the bands involved in the topological band-inversion process are only
p-orbitals. Due to the present of large d-electronic states, the electronic
interaction in this topological insulator is much stronger than that in other
conventional topological insulators. The stability of the new material is
verified by binding energy calculation, phonon modes analysis, and the finite
temperature molecular dynamics simulations. This new material can provide
nearly zero-resistivity signal current for devices and is expected to be
applied in spintronics devices.


title: THz laser based on dipolaritons

abstract:
  We develop the microscopic theory of a terahertz (THz) laser based on the
effects of resonant tunneling in a double quantum well heterostructure embedded
in both optical and THz cavities. In the strong coupling regime the system
hosts dipolaritons, hybrid quasiparticles formed by the direct exciton,
indirect exciton and optical photon, which possess large dipole moments in the
growth direction. Their radiative coupling to the mode of a THz cavity combined
with strong non-linearities provided by exciton-exciton interactions allows for
stable emission of THz radiation in the regime of the continuous optical
excitation. The optimal parameters for maximizing the THz signal output power
are analyzed.


title:
On entropies, $\mathcal{F}$-structures, and scalar curvature of certain
  involutions

abstract:
  In this short note, we analyze geometric properties of orbit spaces of
certain involutions in dimensions four, five, and six. We consider
constructions of $\mathcal{F}$-structures on manifolds of dimension at least
four that allows us to study minimal entropy, minimal volume, collapse with
bounded curvature, and sign of the Yamabe invariant building on work of
Paternain-Petean. The existence of Riemannian metrics of vanishing topological
entropy on the orbit spaces is investigated as well.


title:
New results in open charm spectroscopy through an effective Lagrangian
  approach

abstract:
  An effective Lagrangian approach based on the heavy quark and chiral symmetry
is introduced to analyse the spectroscopy of open charm mesons. Strong two-body
decay widths and ratios of branching fractions are computed, and this piece of
information is used to assign quantum numbers to recently observed charmed
states which still need to be properly classified.


title:
Coalgebraic Trace Semantics for Continuous Probabilistic Transition
  Systems

abstract:
  Coalgebras in a Kleisli category yield a generic definition of trace
semantics for various types of labelled transition systems. In this paper we
apply this generic theory to generative probabilistic transition systems, short
PTS, with arbitrary (possibly uncountable) state spaces. We consider the
sub-probability monad and the probability monad (Giry monad) on the category of
measurable spaces and measurable functions. Our main contribution is that the
existence of a final coalgebra in the Kleisli category of these monads is
closely connected to the measure-theoretic extension theorem for sigma-finite
pre-measures. In fact, we obtain a practical definition of the trace measure
for both finite and infinite traces of PTS that subsumes a well-known result
for discrete probabilistic transition systems. Finally we consider two example
systems with uncountable state spaces and apply our theory to calculate their
trace measures.


title: Infinite Secret Sharing -- Examples

abstract:
  The motivation for extending secret sharing schemes to cases when either the
set of players is infinite or the domain from which the secret and/or the
shares are drawn is infinite or both, is similar to the case when switching to
abstract probability spaces from classical combinatorial probability. It might
shed new light on old problems, could connect seemingly unrelated problems, and
unify diverse phenomena.
  Definitions equivalent in the finitary case could be very much different when
switching to infinity, signifying their difference. The standard requirement
that qualified subsets should be able to determine the secret has different
interpretations in spite of the fact that, by assumption, all participants have
infinite computing power. The requirement that unqualified subsets should have
no, or limited information on the secret suggests that we also need some
probability distribution. In the infinite case events with zero probability are
not necessarily impossible, and we should decide whether bad events with zero
probability are allowed or not.
  In this paper, rather than giving precise definitions, we enlist an abundance
of hopefully interesting infinite secret sharing schemes. These schemes touch
quite diverse areas of mathematics such as projective geometry, stochastic
processes and Hilbert spaces. Nevertheless our main tools are from probability
theory. The examples discussed here serve as foundation and illustration to the
more theory oriented companion paper.


title: Finding Approximate Nash Equilibria of Bimatrix Games via Payoff Queries

abstract:
  We study the deterministic and randomized query complexity of finding
approximate equilibria in bimatrix games. We show that the deterministic query
complexity of finding an $\epsilon$-Nash equilibrium when $\epsilon <
\frac{1}{2}$ is $\Omega(k^2)$, even in zero-one constant-sum games. In
combination with previous results \cite{FGGS13}, this provides a complete
characterization of the deterministic query complexity of approximate Nash
equilibria. We also study randomized querying algorithms. We give a randomized
algorithm for finding a $(\frac{3 - \sqrt{5}}{2} + \epsilon)$-Nash equilibrium
using $O(\frac{k \cdot \log k}{\epsilon^2})$ payoff queries, which shows that
the $\frac{1}{2}$ barrier for deterministic algorithms can be broken by
randomization. For well-supported Nash equilibria (WSNE), we first give a
randomized algorithm for finding an $\epsilon$-WSNE of a zero-sum bimatrix game
using $O(\frac{k \cdot \log k}{\epsilon^4})$ payoff queries, and we then use
this to obtain a randomized algorithm for finding a $(\frac{2}{3} +
\epsilon)$-WSNE in a general bimatrix game using $O(\frac{k \cdot \log
k}{\epsilon^4})$ payoff queries. Finally, we initiate the study of lower bounds
against randomized algorithms in the context of bimatrix games, by showing that
randomized algorithms require $\Omega(k^2)$ payoff queries in order to find a
$\frac{1}{6k}$-Nash equilibrium, even in zero-one constant-sum games. In
particular, this rules out query-efficient randomized algorithms for finding
exact Nash equilibria.


title: Non-invasive light observer

abstract:
  Photonic technologies lack non-invasive monitoring tools to inspect the light
inside optical waveguides. This is one of the main barriers to large scale of
integration, even though photonic platforms are potentially ready to host
several thousands of elements on a single chip. Here, we demonstrate
non-invasive light observation in silicon photonics devices by exploiting
photon interaction with intra-gap energy states localized at the waveguide
surface. Light intensity is measured through a ContactLess Integrated Photonic
Probe (CLIPP) that introduces no measurable extra-photon absorption and a phase
perturbation as low as 0.2 mrad, comparable to thermal fluctuations of less
than 3 mK. Multipoint light monitoring is demonstrated with a sensitivity of
-30 dBm and a dynamic range of 40 dB. CLIPP technology is simple, inherently
CMOS compatible, and scalable to hundreds of probing points per chip. This
concept provides a viable way to real-time conditioning and feedback control of
densely-integrated photonic systems.


title: Repeatable two-mode phase measurement

abstract:
  A measurement scheme to perform a repeatable phase detection on a two-mode
field is presented. The interaction with the probe state (the output state of a
phase-insensitive high-gain amplifier) is described by a Hamiltonian which is
physically realizable in the rotating wave approximation. Information on the
system is obtained through unconventional heterodyne measurements performed on
the probe field after the interaction with the system. The expressions for the
probability distribution and the state reduction are given.


title: Upconversion single photon detection near 2 um

abstract:
  We have demonstrated upconversion detection at the single photon level in the
2 um spectral window using a pump wavelength near 1550nm, a periodically poled
lithium niobate (PPLN) waveguide, and a volume Bragg grating (VBG) to reduce
noise. We achieve a system photon detection efficiency of 10%, with a noise
count rate of 24,500 counts per second, competitive with other 2 um single
photon detection technologies. This detector has potential applications in
environmental gas monitoring, life science, and classical and quantum
communication.


title: Probabilistic Infinite Secret Sharing

abstract:
  The study of probabilistic secret sharing schemes using arbitrary probability
spaces and possibly infinite number of participants lets us investigate
abstract properties of such schemes. It highlights important properties,
explains why certain definitions work better than others, connects this topic
to other branches of mathematics, and might yield new design paradigms.
  A probabilistic secret sharing scheme is a joint probability distribution of
the shares and the secret together with a collection of secret recovery
functions for qualified subsets. The scheme is measurable if the recovery
functions are measurable. Depending on how much information an unqualified
subset might have, we define four scheme types: perfect, almost perfect, ramp,
and almost ramp. Our main results characterize the access structures which can
be realized by schemes of these types.
  We show that every access structure can be realized by a non-measurable
perfect probabilistic scheme. The construction is based on a paradoxical pair
of independent random variables which determine each other.
  For measurable schemes we have the following complete characterization. An
access structure can be realized by a (measurable) perfect, or almost perfect
scheme if and only if the access structure, as a subset of the Sierpi\'nski
space $\{0,1\}^P$, is open, if and only if it can be realized by a span
program. The access structure can be realized by a (measurable) ramp or almost
ramp scheme if and only if the access structure is a $G_\delta$ set
(intersection of countably many open sets) in the Sierpi\'nski topology, if and
only if it can be realized by a Hilbert-space program.


title:
Phonons and Spin Excitations in Fe-Based Superconductor
  Ca10Pt4As8(Fe1-xPtxAs)10 (x ~ 0.2)

abstract:
  By means of neutron inelastic scattering, magnetic excitations and phonons
were measured for a single crystal of slightly overdoped superconductor
Ca10Pt4As8(Fe1-xPtxAs)10 (x ~ 0.2) with the transition temperature Tc of ~33 K.
Below Tc, magnetic excitation spectra \{chi}"(Q, {\omega}) measured at Q = QM
[magnetic {\Gamma} points] are gapped, and in the relatively higher {\omega}
region, the \{chi}"(QM, {\omega})-increase was observed with decreasing T,
where the maximum of the increase was found at ~18 meV at 3 K (<< Tc). These
characteristics are favorable to orbital-fluctuation-mediated superconductivity
with the so-called S++symmetry of the order parameter. The energy dependence of
{\delta}Q-temperature(T) curve of the magnetic excitations seems to have
anomalous behavior in rather wide T region above Tc, {\delta}Q being the width
of the Q scan profile. In the phonon measurements, we observed softening of the
in-plane TA mode, which corresponds to the elastic constant C66. This softening
seems to start at rather high temperature T, as T is lowered. Additionally,
anomalous increase in spectral weights of the TO-phonons at around QM in the
region 35 < {\omega} < 40 meV was found even above Tc, as T is lowered from
ambient T . Because the spectral weights in this {\omega} region mainly
correspond to the in-plane motions of Fe atoms and because orbital fluctuations
are expected to be strong at around QM, the result may present clues to
investigate a possible coupling between the fluctuations of the orbitals and
lattice system.


title: User Selection in MIMO Interfering Broadcast Channels

abstract:
  Interference alignment aims to achieve maximum degrees of freedom in an
interference system. For achieving Interference alignment in interfering
broadcast systems a closed-form solution is proposed in [1] which is an
extension of the grouping scheme in [2]. In a downlink scenario where there are
a large number of users, the base station is required to select a subset of
users such that the sum rate is maximized. To search for the optimal user
subset using brute-force approach is computationally exhaustive because of the
large number of possible user subset combinations. We propose a user selection
algorithm achieving sum rate close to that of optimal solution. The algorithm
employs coordinate ascent approach and exploits orthogonality between the
desired signal space and the interference channel space in the reciprocal
system to select the user at each step. For the sake of completeness, we have
also extended the sum rate approach based algorithm to Interfering broadcast
channel. The complexity of both these algorithms is shown to be linear with
respect to the total number of users as compared to exponential in brute-force
search.


title: Nonequivalence of equivalence principles

abstract:
  Equivalence principles played a central role in the development of general
relativity. Furthermore, they have provided operative procedures for testing
the validity of general relativity, or constraining competing theories of
gravitation. This has led to a flourishing of different, and inequivalent,
formulations of these principles, with the undesired consequence that often the
same name, "equivalence principle", is associated with statements having a
quite different physical meaning. In this paper we provide a precise
formulation of the several incarnations of the equivalence principle,
clarifying their uses and reciprocal relations. We also discuss their possible
role as selecting principles in the design and classification of viable
theories of gravitation.


title:
Imaged sub-stellar companions: not as eccentric as they appear? The
  effect of an unseen inner mass on derived orbits

abstract:
  Increasing numbers of sub-stellar companions are now being discovered via
direct imaging. Orbital elements for some of these objects have been derived
using star--companion astrometry, and several of these appear to have
eccentricities significantly greater than zero. We show that stellar motion
caused by an undetected inner body may result in the companion elements derived
in such a way being incorrect, which could lead to an overestimation of the
eccentricity. The magnitude of this effect is quantified in several regimes and
we derive the maximum eccentricity error a third body could introduce in a
general form, which may be easily applied to any imaged system. Criteria for
identifying systems potentially susceptible to this scenario are presented, and
we find that around half of the planets/companion brown dwarfs currently imaged
could be liable to these errors when their orbital elements are derived. In
particular, this effect could be relevant for systems within 100 pc with
companions at >50 AU, if they also harbour an unseen $\sim$ 10 Jupiter mass
object at $\sim$ 10 AU. We use the Fomalhaut system as an example and show that
a 10% error could be induced on the planet's eccentricity by an observationally
allowed inner mass, which is similar in size to the current error from
astrometry.


title: Musical recommendations and personalization in a social network

abstract:
  This paper presents a set of algorithms used for music recommendations and
personalization in a general purpose social network www.ok.ru, the second
largest social network in the CIS visited by more then 40 millions users per
day. In addition to classical recommendation features like "recommend a
sequence" and "find similar items" the paper describes novel algorithms for
construction of context aware recommendations, personalization of the service,
handling of the cold-start problem, and more. All algorithms described in the
paper are working on-line and are able to detect and address changes in the
user's behavior and needs in the real time.
  The core component of the algorithms is a taste graph containing information
about different entities (users, tracks, artists, etc.) and relations between
them (for example, user A likes song B with certainty X, track B created by
artist C, artist C is similar to artist D with certainty Y and so on). Using
the graph it is possible to select tracks a user would most probably like, to
arrange them in a way that they match each other well, to estimate which items
from a fixed list are most relevant for the user, and more.
  In addition, the paper describes the approach used to estimate algorithms
efficiency and analyze the impact of different recommendation related features
on the users' behavior and overall activity at the service.


title: Fermions on adS

abstract:
  We construct the Feynman propagator for Dirac fermions on anti-de Sitter
space-time and present an analytic expression for the bi-spinor of parallel
transport. We then renormalise the vacuum expectation value of the
stress-energy tensor and end by analysing its renormalised expectation value at
finite temperatures.


title:
Charged Particle Multiplicity and Pseudorapidity Density Measurements in
  pp collisions with ALICE at the LHC

abstract:
  These proceedings describe the charged-particle pseudorapidity densities and
multiplicity distributions measured by the ALICE detector in pp collisions at
$\sqrt{s} = 0.9$ and 7 TeV in specific phase space regions. The pseudorapidity
range $|\eta| < 0.8$, together with $p_{\rm T}$ cuts at 0.15, 0.5 and 1 GeV/$c$
is considered. The classes of events considered are those having at least one
charged particle in the kinematical ranges just described. The results obtained
by ALICE are compared to Monte Carlo predictions.


title: Arratia flow with drift and the Trotter formula for Brownian web

abstract:
  An analog of the Trotter formula for the Arratia flow is presented.
Perturbations of the Brownian web by mappings associated with an ordinary
differential equation with a smooth right part are considered and proved to be
convergent exclusively in the weak sense. The flow obtained as a limit is the
Arratia flow with drift.


title: Radiative topological states in resonant photonic crystals

abstract:
  We present a theory of topological edge states in one-dimensional resonant
photonic crystals with a compound unit cell. Contrary to the traditional
electronic topological states the states under consideration are radiative,
i.e., they decay in time due to the light escape through the structure
boundaries. We demonstrate that the states survive despite their radiative
decay and can be detected both in time- and frequency-dependent light
reflection.


title:
Unified Subharmonic Oscillation Conditions for Peak or Average Current
  Mode Control

abstract:
  This paper is an extension of the author's recent research in which only buck
converters were analyzed. Similar analysis can be equally applied to other
types of converters. In this paper, a unified model is proposed for buck,
boost, and buck-boost converters under peak or average current mode control to
predict the occurrence of subharmonic oscillation. Based on the unified model,
the associated stability conditions are derived in closed forms. The same
stability condition can be applied to buck, boost, and buck-boost converters.
Based on the closed-form conditions, the effects of various converter
parameters including the compensator poles and zeros on the stability can be
clearly seen, and these parameters can be consolidated into a few ones.
High-order compensators such as type-II and PI compensators are considered.
Some new plots are also proposed for design purpose to avoid the instability.
The instability is found to be associated with large crossover frequency. A
conservative stability condition, agreed with the past research, is derived.
The effect of the voltage loop ripple on the instability is also analyzed.


title: UV-IR transmutation for hybrid realizations of Z_k parafermion systems

abstract:
  Recent experiments brought Majorana particles closer to reality and raised
interest in realizing $\mathbb{Z}_k$ parafermions for general value of $k$ in
hybrid structures. Of particular interest is the prospect of realizing a two
dimensional system with the edge states described by $\mathbb{Z}_k$ parafermion
conformal field theory (CFT) by coupling one dimensional hybrid systems.
However in order to understand the effective perturbation due to local
inter-wire coupling, it is crucial to relate short distance ultra-violet (UV)
degrees of freedom to primary fields of the CFT describing long distance
infra-red (IR) physics. Here we consider two recent proposals for realizing a
one dimensional system described by $\mathbb{Z}_k$ parafermion CFT upon tuning
to quantum critical points: a parafermion chain and a pair of $\nu=2/k$ quantum
Hall chiral edge states under uniform backscattering and pairing, where the
latter is represented by self-dual sine-Gordon model. We explicitly derive the
relation between distinct UV degrees of freedom relevant for each proposals and
the primary fields of $\mathbb{Z}_3$ parafermion CFT. Our results point to a
marked difference in the effect of local coupling between wires represented by
each proposals, regarding robustness of the edge states in the resulting two
dimensional systems.


title: Central limit theorem for eigenvectors of heavy tailed matrices

abstract:
  We consider the eigenvectors of symmetric matrices with independent heavy
tailed entries, such as matrices with entries in the domain of attraction of
$\alpha$-stable laws, or adjacencymatrices of Erdos-Renyi graphs. We denote by
$U=[u_{ij}]$ the eigenvectors matrix (corresponding to increasing eigenvalues)
and prove that the bivariate process $$B^n_{s,t}:=n^{-1/2}\sum_{1\le i\le ns,
1\le j\le nt}(|u_{ij}|^2 -n^{-1}),$$ indexed by $s,t\in [0,1]$, converges in
law to a non trivial Gaussian process. An interesting part of this result is
the $n^{-1/2}$ rescaling, proving that from this point of view, the
eigenvectors matrix $U$ behaves more like a permutation matrix (as it was
proved by Chapuy that for $U$ a permutation matrix, $n^{-1/2}$ is the right
scaling) than like a Haar-distributed orthogonal or unitary matrix (as it was
proved by Rouault and Donati-Martin that for $U$ such a matrix, the right
scaling is $1$).


title:
Breakdown of I-Love-Q universality in rapidly rotating relativistic
  stars

abstract:
  It was shown recently, that normalized relations between the moment of
inertia (I), the quadrupole moment (Q) and the tidal deformability (Love
number) exist and for slowly-rotating neutron stars they are almost independent
of the equation of state (EOS). We extend the computation of the I-Q relation
to models rotating up to the mass-shedding limit and show that the universality
of the relations is lost. With increasing rotation rate, the normalized I-Q
relation departs significantly from its slow-rotation limit deviating up to 40%
for neutron stars and up to 75% for strange stars. The deviation is also EOS
dependent and for a broad set of hadronic and strange matter EOS the spread due
to rotation is comparable to the spread due to the EOS, if one considers
sequences with fixed rotational frequency. Still, for a restricted sample of
modern realistic EOS one can parameterize the deviations from universality as a
function of rotation only. The previously proposed I-Love-Q relations should
thus be used with care, because they lose their universality in astrophysical
situations involving compact objects rotating faster than a few hundred Hz.


title: RGE Effects on neutrino masses in partial split supersymmetry

abstract:
  We show that the running of the Higgs-gaugino-higgsino couplings present in
Partial Split Supersymmetry can severely affect the neutrino masses generated
through Bilinear R-parity Violation. We find a working scenario where the
predicted neutrino observables satisfy the experimental constraints when the
running is neglected. After including the running, we show that already with a
split supersymmetric scale of 10000 GeV the atmospheric mass leaves the allowed
experimental window, and that the solar mass leaves it even earlier, with a
split supersymmetric scale of 1000 GeV. This shows that the correct prediction
of neutrino observables in these models necessitates the inclusion of the
running of these couplings.


title: Action at a distance and causality in quantum theory

abstract:
  The relation between quantum theory and special relativity is peculiar. On
the one hand it is close and essential. Steven Weinberg [1], for example, takes
the position that the standard model is an inevitable consequence of the
marriage of the two theories. On the other, the action at a distance implied by
the famous paper by Einstein, Podolsky, and Rosen [2] is certainly contrary to
the implications of special relativity in spite of the fact that it does not
allow transmission of information. The setting of quantum theory is a Hilbert
spaceH and a path inH whose development in time is governed by a one parameter
group of unitary transformations while the setting for special relativity can
be thought of as Minkowski space with the time development not absolute, but
dependent on the inertial system of the observer. The problem is to show how
these two very different viewpoints can be reconciled in a way that includes an
explanation of the "action at a distance" conundrum.


title: Ntuples for NLO Events at Hadron Colliders

abstract:
  We present an event-file format for the dissemination of
next-to-leading-order (NLO) predictions for QCD processes at hadron colliders.
The files contain all information required to compute generic jet-based
infrared-safe observables at fixed order (without showering or hadronization),
and to recompute observables with different factorization and renormalization
scales. The files also make it possible to evaluate cross sections and
distributions with different parton distribution functions. This in turn makes
it possible to estimate uncertainties in NLO predictions of a wide variety of
observables without recomputing the short-distance matrix elements. The event
files allow a user to choose among a wide range of commonly-used jet algorithms
and jet-size parameters.
  We provide event files for a $W$ or $Z$ boson accompanied by up to four jets,
and for pure-jet events with up to four jets. The files are for the Large
Hadron Collider with a center of mass energy of 7 or 8 TeV.
  A C++ library along with a Python interface for handling these files are also
provided and described in this article. The library allows a user to read the
event files and recompute observables transparently for different pdf sets and
factorization and renormalization scales.


title:
Neural perceptual model to global-local vision for recognition of the
  logical structure of administrative documents

abstract:
  This paper gives the definition of Transparent Neural Network "TNN" for the
simulation of the globallocal vision and its application to the segmentation of
administrative document image. We have developed and have adapted a recognition
method which models the contextual effects reported from studies in
experimental psychology. Then, we evaluated and tested the TNN and the
multi-layer perceptron "MLP", which showed its effectiveness in the field of
the recognition, in order to show that the TNN is clearer for the user and more
powerful on the level of the recognition. Indeed, the TNN is the only system
which makes it possible to recognize the document and its structure.


title:
Hierarchical Clustering of Hyperspectral Images using Rank-Two
  Nonnegative Matrix Factorization

abstract:
  In this paper, we design a hierarchical clustering algorithm for
high-resolution hyperspectral images. At the core of the algorithm, a new
rank-two nonnegative matrix factorizations (NMF) algorithm is used to split the
clusters, which is motivated by convex geometry concepts. The method starts
with a single cluster containing all pixels, and, at each step, (i) selects a
cluster in such a way that the error at the next step is minimized, and (ii)
splits the selected cluster into two disjoint clusters using rank-two NMF in
such a way that the clusters are well balanced and stable. The proposed method
can also be used as an endmember extraction algorithm in the presence of pure
pixels. The effectiveness of this approach is illustrated on several synthetic
and real-world hyperspectral images, and shown to outperform standard
clustering techniques such as k-means, spherical k-means and standard NMF.


title:
Ranking basic belief assignments in decision making under uncertain
  environment

abstract:
  Dempster-Shafer theory (D-S theory) is widely used in decision making under
the uncertain environment. Ranking basic belief assignments (BBAs) now is an
open issue. Existing evidence distance measures cannot rank the BBAs in the
situations when the propositions have their own ranking order or their inherent
measure of closeness. To address this issue, a new ranking evidence distance
(RED) measure is proposed. Compared with the existing evidence distance
measures including the Jousselme's distance and the distance between betting
commitments, the proposed RED measure is much more general due to the fact that
the order of the propositions in the systems is taken into consideration. If
there is no order or no inherent measure of closeness in the propositions, our
proposed RED measure is reduced to the existing evidence distance. Numerical
examples show that the proposed RED measure is an efficient alternative to rank
BBAs in decision making under uncertain environment.


title:
On Convergent Finite Difference Schemes for Variational - PDE Based
  Image Processing

abstract:
  We study an adaptive anisotropic Huber functional based image restoration
scheme. By using a combination of L2-L1 regularization functions, an adaptive
Huber functional based energy minimization model provides denoising with edge
preservation in noisy digital images. We study a convergent finite difference
scheme based on continuous piecewise linear functions and use a variable
splitting scheme, namely the Split Bregman, to obtain the discrete minimizer.
Experimental results are given in image denoising and comparison with additive
operator splitting, dual fixed point, and projected gradient schemes illustrate
that the best convergence rates are obtained for our algorithm.


title: Source Delay in Mobile Ad Hoc Networks

abstract:
  Source delay, the time a packet experiences in its source node, serves as a
fundamental quantity for delay performance analysis in networks. However, the
source delay performance in highly dynamic mobile ad hoc networks (MANETs) is
still largely unknown by now. This paper studies the source delay in MANETs
based on a general packet dispatching scheme with dispatch limit $f$ (PD-$f$
for short), where a same packet will be dispatched out up to $f$ times by its
source node such that packet dispatching process can be flexibly controlled
through a proper setting of $f$. We first apply the Quasi-Birth-and-Death (QBD)
theory to develop a theoretical framework to capture the complex packet
dispatching process in PD-$f$ MANETs. With the help of the theoretical
framework, we then derive the cumulative distribution function as well as mean
and variance of the source delay in such networks. Finally, extensive
simulation and theoretical results are provided to validate our source delay
analysis and illustrate how source delay in MANETs are related to network
parameters.


title: Generalized Fitting subgroups of finite groups

abstract:
  In this paper we consider the Fitting subgroup $F(G)$ of a finite group $G$
and its generalizations: the quasinilpotent radical $F^*(G)$ and the
generalized Fitting subgroup $\tilde{F}(G)$ defined by $\tilde{F}(G)\supseteq
\Phi(G)$ and $\tilde{F}(G)/\Phi(G)=Soc(G/\Phi(G))$. We sum up known properties
of $\tilde{F}(G)$ and suggest some new ones. Let $R$ be a subgroup of a group
$G$. We shall call a subgroup $H$ of $G$ the $R$-subnormal subgroup if $H$ is
subnormal in $ \langle H,R\rangle$. In this work the influence of $R$-subnormal
subgroups (maximal, Sylow, cyclic primary) on the structure of finite groups
are studied in the case when $R\in\{F(G), F^*(G),\tilde{F}(G)\}$.


title:
Radial Transport of Large-Scale Magnetic Fields in Accretion Disks. I.
  Steady Solutions and an Upper Limit on the Vertical Field Strength

abstract:
  Large-scale magnetic fields are key ingredients of magnetically driven disk
accretion. We study how large-scale poloidal fields evolve in accretion disks,
with the primary aim of quantifying the viability of magnetic accretion
mechanisms in protoplanetary disks. We employ a kinematic mean-field model for
poloidal field transport and focus on steady states where inward advection of a
field balances with outward diffusion due to effective resistivities. We
analytically derive the steady-state radial distribution of poloidal fields in
highly conducting accretion disks. The analytic solution reveals an upper limit
on the strength of large-scale vertical fields attainable in steady states. Any
excess poloidal field will be diffused away within a finite time, and we
demonstrate this with time-dependent numerical calculations of the mean-field
equations. We apply this upper limit to large-scale vertical fields threading
protoplanetary disks. We find that the maximum attainable strength is about 0.1
G at 1 AU, and about 1 mG at 10 AU from the central star. When combined with
recent magnetic accretion models, the maximum field strength translates into
the maximum steady-state accretion rate of $\sim 10^{-7} M_\odot {\rm
yr}^{-1}$, in agreement with observations. We also find that the maximum field
strength is ~ 1 kG at the surface of the central star provided that the disk
extends down to the stellar surface. This implies that any excess stellar
poloidal field of strength >~ kG can be transported to the surrounding disk.
This might in part resolve the magnetic flux problem in star formation.


title: Impulse Noise Removal In Speech Using Wavelets

abstract:
  A new method for removing impulse noise from speech in the wavelet transform
domain is proposed. The method utilizes the multiresolution property of the
wavelet transform, which provides finer time resolution at the higher
frequencies than the short-time Fourier transform (STFT), to effectively
identify and remove impulse noise. It uses two features of speech to
discriminate speech from impulse noise: one is the slow time-varying nature of
speech and the other is the Lipschitz regularity of the speech components. On
the basis of these features, an algorithm has been developed to identify and
suppress wavelet coefficients that correspond to impulse noise. Experiment
results show that the new method is able to significantly reduce impulse noise
without degrading the quality of the speech signal or introducing any audible
artifacts.


title:
An iterative algorithm for computed tomography image reconstruction from
  limited-angle projections

abstract:
  In application of tomography imaging, limited-angle problem is a quite
practical and important issue. In this paper, an iterative
reprojection-reconstruction (IRR) algorithm using a modified Papoulis-Gerchberg
(PG) iterative scheme is developed for reconstruction from limited-angle
projections which contain noise. The proposed algorithm has two iterative
update processes, one is the extrapolation of unknown data, and the other is
the modification of the known noisy observation data. And the algorithm
introduces scaling factors to control the two processes, respectively. The
convergence of the algorithm is guaranteed, and the method of choosing the
scaling factors is given with energy constraints. The simulation result
demonstrates our conclusions and indicates that the algorithm proposed in this
paper can obviously improve the reconstruction quality.


title: Deadlock detection in linear recursive programs

abstract:
  Deadlock detection in recursive programs that admit dynamic resource creation
is extremely complex and solutions either give imprecise answers or do not
scale.
  We define an algorithm for detecting deadlocks of "linear recursive programs"
of a basic model. The theory that underpins the algorithm is a generalization
of the theory of permutations of names to so-called "mutations", which
transform tuples by introducing duplicates and fresh names.
  Our algorithm realizes the back-end of deadlock analyzers for object-oriented
programming languages, once the association programs/basic-model-programs has
been defined as front-end.


title:
Channel Flow of a Tensorial Shear-Thinning Maxwell Model: Lattice
  Boltzmann Simulations

abstract:
  We introduce a nonlinear generalized tensorial Maxwell-type constitutive
equation to describe shear-thinning glass-forming fluids, motivated by a recent
microscopic approach to the nonlinear rheology of colloidal suspensions. The
model captures a nonvanishing dynamical yield stress at the glass transition
and incorporates normal-stress differences. A modified lattice-Boltzmann (LB)
simulation scheme is presented that includes non-Newtonian contributions to the
stress tensor and deals with flow-induced pressure differences. We test this
scheme in pressure-driven 2D Poiseuille flow of the nonlinear generalized
Maxwell fluid. In the steady state, comparison with an analytical solution
shows good agreement. The transient dynamics after startup and cessation of the
pressure gradient are studied; the simulation reproduces a finite stopping time
for the cessation flow of the yield-stress fluid in agreement with previous
analytical estimates.


title:
Emergence of pressure-induced metamagnetic-like state in Mn-doped
  CdGeAs2 chalcopyrite

abstract:
  The effect of hydrostatic pressure on resistivity and magnetic ac
susceptibility has been studied in Mn-doped CdGeAs2 room-temperature (RT)
ferromagnetic chalcopyrite with two types of MnAs micro-clusters. The slight
increase of temperature by about 30 K in the region between RT and Curie
temperature TC causes a significant change in the positions of pressure-induced
semiconductor-metal transition and magnetic phase transitions in low pressure
area. By conducting measurements of the anomalous Hall resistance in the field
H \leq 5 kOe, we present experimental evidence for pressure-induced
metamagnetic-like state during the paramagnetic phase at pressure P = 5 GPa.


title:
How Much Should I Pay for Privacy Concerns in Truthful Online Crowd
  Sensing?

abstract:
  Crowd sensing is a new paradigm which leverages the pervasive smartphones to
efficiently collect sensing data, enabling numerous novel applications. To
achieve good service quality for a crowd sensing application, incentive
mechanisms are indispensable to attract more user participation. Most of
existing mechanisms only apply for the offline scenario, where the system has
full information about the users' sensing profiles, i.e., a set of locations or
mobility as well as the type of smartphones used, and their true costs. On the
contrary, we focus on a more real scenario where users with their own privacy
concerns arrive one by one online in a random order. We model the problem as a
privacy-respecting online auction in which users are willing to negotiate
access to certain private information and submit their sensing profiles
satisfying privacy concerns to the platform (the provider of crowd sensing
applications) over time, and the platform aims to the total total value of the
services provided by selected users under a budget constraint. We then design
two online mechanisms for a budgeted crowd sensing application, satisfying the
computational efficiency, individual rationality, budget feasibility,
truthfulness, consumer sovereignty, constant competitiveness and privacy
concerns. Through extensive simulations, we evaluate the performance and
validate the theoretical properties of our online mechanisms.


title:
OutFlank Routing: Increasing Throughput in Toroidal Interconnection
  Networks

abstract:
  We present a new, deadlock-free, routing scheme for toroidal interconnection
networks, called OutFlank Routing (OFR). OFR is an adaptive strategy which
exploits non-minimal links, both in the source and in the destination nodes.
When minimal links are congested, OFR deroutes packets to carefully chosen
intermediate destinations, in order to obtain travel paths which are only an
additive constant longer than the shortest ones. Since routing performance is
very sensitive to changes in the traffic model or in the router parameters, an
accurate discrete-event simulator of the toroidal network has been developed to
empirically validate OFR, by comparing it against other relevant routing
strategies, over a range of typical real-world traffic patterns. On the
16x16x16 (4096 nodes) simulated network OFR exhibits improvements of the
maximum sustained throughput between 14% and 114%, with respect to Adaptive
Bubble Routing.


title:
Comparison of Gravitational Wave Detector Network Sky Localization
  Approximations

abstract:
  Gravitational waves emitted during compact binary coalescences are a
promising source for gravitational-wave detector networks. The accuracy with
which the location of the source on the sky can be inferred from gravitational
wave data is a limiting factor for several potential scientific goals of
gravitational-wave astronomy, including multi-messenger observations. Various
methods have been used to estimate the ability of a proposed network to
localize sources. Here we compare two techniques for predicting the uncertainty
of sky localization -- timing triangulation and the Fisher information matrix
approximations -- with Bayesian inference on the full, coherent data set. We
find that timing triangulation alone tends to over-estimate the uncertainty in
sky localization by a median factor of $4$ for a set of signals from
non-spinning compact object binaries ranging up to a total mass of $20
M_\odot$, and the over-estimation increases with the mass of the system. We
find that average predictions can be brought to better agreement by the
inclusion of phase consistency information in timing-triangulation techniques.
However, even after corrections, these techniques can yield significantly
different results to the full analysis on specific mock signals. Thus, while
the approximate techniques may be useful in providing rapid, large scale
estimates of network localization capability, the fully coherent Bayesian
analysis gives more robust results for individual signals, particularly in the
presence of detector noise.


title:
The Rigorous Stochastic Matrix Multiplication Scheme for the
  Calculations of Reduced Equilibrium Density Matrices of Open Multilevel
  Quantum Systems

abstract:
  Understanding the roles of the temporary and spatial structures of quantum
functional noise in open multilevel quantum molecular systems attracts a lot of
theoretical interests. I want to establish a rigorous and general framework for
functional quantum noises from the constructive and computational perspectives,
$\it{i.e.}$ how to generate the random trajectories to reproduce the kernel and
path ordering of the influence functional with effective Monte Carlo methods
for arbitrary spectral densities. This construction approach aims to unify the
existing stochastic models to rigorously describe the temporary and spatial
structure of Gaussian quantum noises. In this paper, I review the Euclidean
imaginary time influence functional and propose the stochastic matrix
multiplication scheme to calculate reduced equilibrium density matrices (REDM).
  In addition, I review and discuss the Feynman-Vernom influence functional
according to the Gaussian quadratic integral, particularly its imaginary part
which is critical to the rigorous description of the quantum detailed balance.
As a result, I establish the conditions under which the influence functional
can be interpreted as the average of exponential functional operator over
real-valued Gaussian processes for open multilevel quantum systems. I also show
the difference between the local and nonlocal phonons within this framework.
With the stochastic matrix multiplication scheme, I compare the normalized REDM
with the Boltzmann equilibrium distribution for open multilevel quantum
systems.


title: Error Analysis of Nuclear Matrix Elements

abstract:
  We estimate the expected errors of nuclear matrix elements coming from the
uncertainty on the NN interaction. We use a coarse grained (GR) interaction
fitted to NN scattering data, with several prescriptions for the long-part of
the interaction, including one pion exchange and chiral two-pion exchange
interactions.


title: Measurements without Probabilities in the Final State Proposal

abstract:
  The black hole final state proposal reconciles the infalling vacuum with the
unitarity of the Hawking radiation, but only for some experiments. We study
experiments that first verify the exterior, then the interior purification of
the same Hawking particle. (This is the same protocol that renders the firewall
paradox operationally meaningful in standard quantum mechanics.) We show that
the decoherence functional fails to be diagonal, even upon inclusion of
external "pointer" systems. Hence, probabilities for outcomes of these
measurements are not defined. We conclude that the final state proposal does
not offer a consistent alternative to the firewall hypothesis.


title: Random walks generated by equilibrium contact processes

abstract:
  We consider dynamic random walks where the nearest neighbour jump rates are
determined by an underlying supercritical contact process in equilibrium. This
has previously been studied by den Hollander and dos Santos and den Hollander,
dos Santos, Sidoravicius. We show the CLT for such a random walk, valid for all
supercritical infection rates for the contact process environment.


title:
Second Harmonic Generation in h-BN and MoS$_2$ monolayers: the role of
  electron-hole interaction

abstract:
  In this letter we show by means of first principle numerical simulations that
electron-hole interaction significantly contributes to the second-harmonic
generation spectrum of h-BN or MoS$_2$ monolayers. Specifically, it doubles the
signal intensity at the excitonic resonances with respect to the contribution
from independent electronic transitions. This result hints that the intensity
of second-harmonic signal of those materials can be tuned by changing the
dielectric screening, that controls the strength of the electron-hole
interaction.


title:
Direct optical sensing of single unlabeled small proteins and
  super-resolution microscopy of their binding sites

abstract:
  More than twenty years ago, scientists succeeded in pushing the limits of
optical detection to single molecules using fluorescence. This breakthrough has
revolutionized biophysical measurements, but restrictions in photophysics and
labeling protocols have motivated many efforts to achieve fluorescence-free
single-molecule sensitivity in biological studies. Although several interesting
mechanisms using vibrational spectroscopy, photothermal detection, plasmonics
or microcavities have been proposed for biosensing at the single-protein level,
no method has succeeded in direct label-free detection of single proteins.
Here, we present the first results using interferometric detection of
scattering (iSCAT) from single proteins without the need for any label, optical
nanostructure or microcavity. Furthermore, we demonstrate super-resolution
imaging of protein binding with nanometer localization precision. The ease of
iSCAT instrumentation promises a breakthrough for industrial usage as well as
fundamental laboratory experiments.


title:
Tuneable drug-loading capability of chitosan hydrogels with varied
  network architectures

abstract:
  Advanced bioactive systems with defined macroscopic properties and
spatio-temporal sequestration of extracellular biomacromolecules are highly
desirable for next generation therapeutics. Here, chitosan hydrogels were
prepared with neutral or negatively-charged crosslinkers in order to promote
selective electrostatic complexation with charged drugs. Chitosan (CT) was
functionalised with varied dicarboxylic acids, such as tartaric acid (TA),
poly(ethylene glycol) bis(carboxymethyl) ether (PEG), 1.4-Phenylenediacetic
acid (4Ph) and 5-Sulfoisophthalic acid monosodium salt (PhS), whereby PhS was
hypothesised to act as a simple mimetic of heparin. ATR FT-IR showed the
presence of C=O amide I, N-H amide II and C=O ester bands, providing evidence
of covalent network formation. The crosslinker content was reversely quantified
by 1H-NMR on partially-degraded network oligomers, so that 18 mol% PhS was
exemplarily determined. Swellability, compressability, material morphology, and
drug-loading capability were successfully adjusted based on the selected
network architecture. Here, hydrogel incubation with model drugs of varied
electrostatic charge, i.e. allura red (AR, --), methyl orange (MO, -) or
methylene blue (MB, +), resulted in direct hydrogel-dye electrostatic
complexation. Importantly, the cationic compound, MB, showed different
incorporation behaviours, depending on the electrostatic character of the
selected crosslinker. In light of this tuneable drug-loading capability, these
CT hydrogels would be highly attractive as drug reservoirs towards e.g. the
fabrication of tissue models in vitro.


title:
Asymptotic Properties of Bayes Risk of a General Class of Shrinkage
  Priors in Multiple Hypothesis Testing Under Sparsity

abstract:
  Consider the problem of simultaneous testing for the means of independent
normal observations. In this paper, we study some asymptotic optimality
properties of certain multiple testing rules induced by a general class of
one-group shrinkage priors in a Bayesian decision theoretic framework, where
the overall loss is taken as the number of misclassified hypotheses. We assume
a two-groups normal mixture model for the data and consider the asymptotic
framework adopted in Bogdan et al. (2011) who introduced the notion of
asymptotic Bayes optimality under sparsity in the context of multiple testing.
The general class of one-group priors under study is rich enough to include,
among others, the families of three parameter beta, generalized double Pareto
priors, and in particular the horseshoe, the normal-exponential-gamma and the
Strawderman-Berger priors. We establish that within our chosen asymptotic
framework, the multiple testing rules under study asymptotically attain the
risk of the Bayes Oracle up to a multiplicative factor, with the constant in
the risk close to the constant in the Oracle risk. This is similar to a result
obtained in Datta and Ghosh (2013) for the multiple testing rule based on the
horseshoe estimator introduced in Carvalho et al. (2009, 2010). We further show
that under very mild assumption on the underlying sparsity parameter, the
induced decision rules based on an empirical Bayes estimate of the
corresponding global shrinkage parameter proposed by van der Pas et al. (2014),
attain the optimal Bayes risk up to the same multiplicative factor
asymptotically. We provide a unifying argument applicable for the general class
of priors under study. In the process, we settle a conjecture regarding
optimality property of the generalized double Pareto priors made in Datta and
Ghosh (2013). Our work also shows that the result in Datta and Ghosh (2013) can
be improved further.


title: Simulating cosmic reionization: How large a volume is large enough?

abstract:
  We present the largest-volume (425 Mpc/h=607 Mpc on a side) full radiative
transfer simulation of cosmic reionization to date. We show that there is
significant additional power in density fluctuations at very large scales. We
systematically investigate the effects this additional power has on the
progress, duration and features of reionization, as well as on selected
reionization observables. We find that comoving simulation volume of ~100 Mpc/h
per side is sufficient for deriving a convergent mean reionization history, but
that the reionization patchiness is significantly underestimated. We use
jackknife splitting to quantify the convergence of reionization properties with
simulation volume for both mean-density and variable-density sub-regions. We
find that sub-volumes of ~100 Mpc/h per side or larger yield convergent
reionization histories, except for the earliest times, but smaller volumes of
~50 Mpc/h or less are not well converged at any redshift. Reionization history
milestones show significant scatter between the sub-volumes, of Delta z=0.6-1
for ~50 Mpc/h volumes, decreasing to Delta z=0.3-0.5 for ~100 Mpc/h volumes,
and $\Delta z$~0.1 for ~200 Mpc/h volumes. If we only consider mean-density
sub-regions the scatter decreases, but remains at Delta z~0.1-0.2 for the
different size sub-volumes. Consequently, many potential reionization
observables like 21-cm rms, 21-cm PDF skewness and kurtosis all show good
convergence for volumes of ~200 Mpc/h, but retain considerable scatter for
smaller volumes. In contrast, the three-dimensional 21-cm power spectra at
large scales (k<0.25 h/Mpc) do not fully converge for any sub-volume size.
These additional large-scale fluctuations significantly enhance the 21-cm
fluctuations, which should improve the prospects of detection considerably,
given the lower foregrounds and greater interferometer sensitivity at higher
frequencies. (abridged)


title:
Asteroseismology of DAV star HS0507+0434B, including the core
  composition profiles

abstract:
  The DAV star, HS0507+0434B, was observed by Fu et al. (2013) in 2007 and from
2009 December to 2010 January. There were a total of six triplets with nearly
equal split, which were identified as $l$ = 1 modes caused by rotation. In
order to fit the six $l$ = 1 modes, grids of white dwarf models are generated
by WDEC. For the core composition profiles, we choose the linear fittings to
carbon profile of white dwarf models from MESA, which can be considered as
results of real nuclear burning process. Coupled with diffusion equilibrium
H/He and He/C mixtures, we make grids of models in WDEC and do asteroseismology
works on HS0507+0434B. There is a total of 9.50 seconds error for our
best-fitting model, which is smaller than the result (a total of 22.1 seconds
error) of Fu et al. (2013), when fitting the six $l$ = 1 modes. The two other
previous identified pulsation mode frequencies (286.1 s and 743.40 s) may also
be well fitted by our best-fitting model. The model parameters are $T_{eff}$ =
11450 K, log$g$ = 8.088, $M_{*}$ = 0.640 $M_{\odot}$, log($M_{H}$/$M_{*}$) =
-6, and log($M_{He}$/$M_{*}$) = -3.


title: Pion electromagnetic form factor in the Covariant Spectator Theory

abstract:
  The pion electromagnetic form factor at spacelike momentum transfer is
calculated in relativistic impulse approximation using the Covariant Spectator
Theory. The same dressed quark mass function and the equation for the pion
bound-state vertex function as discussed in the companion paper are used for
the calculation, together with a dressed quark current that satisfies the
Ward-Takahashi identity. The results obtained for the pion form factor are in
agreement with experimental data, they exhibit the typical monopole behavior at
high-momentum transfer, and they satisfy some remarkable scaling relations.


title: Transport coefficients of the QGP

abstract:
  The FASTSUM collaboration presents a study on the temperature dependence of
the electrical conductivity $\sigma$ in the quark-gluon plasma, using the
methods of lattice QCD. Correlators of the exactly conserved vector current are
measured at different temperatures across the deconfinement transition, using
ensembles of $2+1$ flavours of dynamical fermions on anisotropic lattices. We
then employ bayesian methods (MEM) to extract the relevant spectral functions,
which are found to be consistent with $\sigma/T$ rising as a function of $T$.
The robustness of the results is verified by a detailed analysis of the
systematics involved in the bayesian reconstruction of the spectral functions.


title: Hypothesis Testing for Topological Data Analysis

abstract:
  Persistent homology is a vital tool for topological data analysis. Previous
work has developed some statistical estimators for characteristics of
collections of persistence diagrams. However, tools that provide statistical
inference for observations that are persistence diagrams are limited.
Specifically, there is a need for tests that can assess the strength of
evidence against a claim that two samples arise from the same population or
process. We propose the use of randomization-style null hypothesis significance
tests (NHST) for these situations. The test is based on a loss function that
comprises pairwise distances between the elements of each sample and all the
elements in the other sample. We use this method to analyze a range of
simulated and experimental data. Through these examples we experimentally
explore the power of the p-values. Our results show that the
randomization-style NHST based on pairwise distances can distinguish between
samples from different processes, which suggests that its use for hypothesis
tests upon persistence diagrams is reasonable. We demonstrate its application
on a real dataset of fMRI data of patients with ADHD.


title: The Real Dynamics of Bieberbach's Example

abstract:
  Bieberbach constructed in 1933 domains in $ \bf {C}^2$ which were
biholomorphic to $ \bf {C}^2$ but not dense. The existence of such domains was
unexpected. The special domains Bieberbach considered are basins of attraction
of a cubic H\'enon map. This classical method of construction is one of the
first applications of dynamical systems to complex analysis. In this paper, the
boundaries of the real sections of Bieberbach's domains will be calculated
explicitly as the stable manifolds of the saddle points. The real filled Julia
sets and the real Julia sets of Bieberbach's map will also be calculated
explicitly and illustrated with computer generated graphics. Basic differences
between real and the complex dynamics will be shown.


title:
Mining the Temporal Evolution of the Android Bug Reporting Community via
  Sliding Windows

abstract:
  The open source development community consists of both paid and volunteer
developers as well as new and experienced users. Previous work has applied
social network analysis (SNA) to open source communities and has demonstrated
value in expertise discovery and triaging. One problem with applying SNA
directly to the data of the entire project lifetime is that the impact of local
activities will be drowned out. In this paper we provide a method for
aggregating, analyzing, and visualizing local (small time periods) interactions
of bug reporting participants by using the SNA to measure the betweeness
centrality of these participants. In particular we mined the Android bug
repository by producing social networks from overlapping 30-day windows of bug
reports, each sliding over by day. In this paper we define three patterns of
participant behaviour based on their local centrality. We propose a method of
analyzing the centrality of bug report participants both locally and globally,
then we conduct a thorough case study of the bug reporter's activity within the
Android bug repository. Furthermore, we validate the conclusions of our method
by mining the Android version control system and inspecting the Android release
history. We found that windowed SNA analysis elicited local behaviour that were
invisible during global analysis.


title:
Conductance through disordered graphene nanoribbons: Standard and
  anomalous electron localization

abstract:
  Conductance fluctuations produced by the presence of disorder in zigzag and
armchair graphene nanoribbons are studied. We show that quantum transport in
zigzag nanoribbons takes place via edge states which are exponentially
localized, as in the standard Anderson localization problem, whereas for
armchair nanoribbons the symmetry of the graphene sublattices produces
anomalous localization, or delocalization. We show that these two different
electron localizations lead to significant differences of the conductance
statistics between zigzag and armchair nanoribbons. In particular, armchair
nanoribbons show nonconventional large conductance fluctuations relative to
those of Anderson-localized electrons. We calculate analytically the complete
distribution of conductances for both types of ribbons. Without free fitting
parameters, we verify our theoretical results by performing numerical
simulations of disordered zigzag and armchair nanoribbons of experimentally
achievable lengths and widths.


title: One-Loop Matching for Parton Distributions: Non-Singlet Case

abstract:
  We derive one-loop matching condition for non-singlet quark distributions in
transverse-momentum cut-off scheme, including unpolarized, helicity and
transversity distributions. The matching is between the quasi-distribution
defined by static correlation at finite nucleon momentum and the light-cone
distribution measurable in experiments. The result is useful for extracting the
latter from the former in a lattice QCD calculation.


title:
Semistability of Principal Bundles on a K\"ahler Manifold with a
  Non-Connected Structure Group

abstract:
  We investigate principal $G$-bundles on a compact K\"ahler manifold, where
$G$ is a complex algebraic group such that the connected component of it
containing the identity element is reductive. Defining (semi)stability of such
bundles, it is shown that a principal $G$-bundle $E_G$ admits an
Einstein-Hermitian connection if and only if $E_G$ is polystable. We give an
equivalent formulation of the (semi)stability condition. A question is to
compare this definition with that of math.AG/0506511.


title:
Connectivity of confined 3D Networks with Anisotropically Radiating
  Nodes

abstract:
  Nodes in ad hoc networks with randomly oriented directional antenna patterns
typically have fewer short links and more long links which can bridge together
otherwise isolated subnetworks. This network feature is known to improve
overall connectivity in 2D random networks operating at low channel path loss.
To this end, we advance recently established results to obtain analytic
expressions for the mean degree of 3D networks for simple but practical
anisotropic gain profiles, including those of patch, dipole and end-fire array
antennas. Our analysis reveals that for homogeneous systems (i.e. neglecting
boundary effects) directional radiation patterns are superior to the isotropic
case only when the path loss exponent is less than the spatial dimension.
Moreover, we establish that ad hoc networks utilizing directional transmit and
isotropic receive antennas (or vice versa) are always sub-optimally connected
regardless of the environment path loss. We extend our analysis to investigate
boundary effects in inhomogeneous systems, and study the geometrical reasons
why directional radiating nodes are at a disadvantage to isotropic ones.
Finally, we discuss multi-directional gain patterns consisting of many equally
spaced lobes which could be used to mitigate boundary effects and improve
overall network connectivity.

categories: cs.IT cond-mat.dis-nn cond-mat.stat-mech cs.NI math.IT


title: Cyclotomic Carter-Payne homomorphisms

abstract:
  We construct a new family of homomorphisms between (graded) Specht modules of
the quiver Hecke algebras of type A. These maps have many similarities with the
homomorphisms constructed by Carter and Payne in the special case of the
symmetric groups, although the maps that we obtain are both more and less
general than these.


title:
Long-Lived Vortex Structures in Collisional Pure and Gas-Discharge
  Nonneutral Electron Plasmas

abstract:
  The analysis of experimental investigations of equilibrium, interaction and
dynamics of vortex structures in pure electron and gas-discharge electron
nonneutral plasmas during the time much more than the electron-neutral
collision time has been carried out. The problem of long confinement of the
column of pure electron plasma in Penning-Malmberg trap is considered. The
mechanism of stability of long-lived vortex structure in gas-discharge
nonneutral electron plasma is investigated. The collapse of electron sheath in
gas-discharge nonneutral electron plasma in Penning cell at high pressures of
neutral gas is described. The interaction between the stable vortex structure
and the annular electron sheath, and the action of vortex structures on the
transport of electrons along and across the magnetic field are discussed.


title: Strongly Koszul edge rings

abstract:
  We classify the finite connected simple graphs whose edge rings are strongly
Koszul. From the classification, it follows that if the edge ring is strongly
Koszul, then its toric ideal possesses a quadratic Gr\"obner basis.


title:
Non-commutative integration, zeta functions and the Haar state for
  $SU_{q}(2)$

abstract:
  We study a notion of non-commutative integration, in the spirit of modular
spectral triples, for the quantum group $SU_{q}(2)$. In particular we define
the non-commutative integral as the residue at the spectral dimension of a zeta
function, which is constructed using a Dirac operator and a weight. We consider
the Dirac operator introduced by Kaad and Senior and a family of weights
depending on two parameters, which are related to the diagonal automorphisms of
$SU_{q}(2)$. We show that, after fixing one of the parameters, the
non-commutative integral coincides with the Haar state of $SU_{q}(2)$. Moreover
we can impose an additional condition on the zeta function, which also fixes
the second parameter. For this unique choice the spectral dimension coincides
with the classical dimension.


title: Phenomenology of neutrino oscillations and mixing

abstract:
  We review the status of three-neutrino mixing and the results of global
analyses of short-baseline neutrino oscillation data in 3+1 and 3+2 neutrino
mixing schemes.


title:
Weak Convergence Rates of Population versus Single-Chain Stochastic
  Approximation MCMC Algorithms

abstract:
  In this paper, we establish the theory of weak convergence (toward a normal
distribution) for both single-chain and population stochastic approximation
MCMC algorithms. Based on the theory, we give an explicit ratio of convergence
rates for the population SAMCMC algorithm and the single-chain SAMCMC
algorithm. Our results provide a theoretic guarantee that the population SAMCMC
algorithms are asymptotically more efficient than the single-chain SAMCMC
algorithms when the gain factor sequence decreases slower than O(1/t), where t
indexes the number of iterations. This is of interest for practical
applications.


title:
New identities for the polarized partitions and partitions with
  $d$-distant parts

abstract:
  In this paper we present a new class of integer partition identities. The
number of partitions with d-distant parts can be represented as a sum of the
number of partitions with 1-distant parts whose even parts are greater than
twice the number of odd parts. We also provide a direct bijection between these
classes of partitions.


title: McMullen polynomials and Lipschitz flows for free-by-cyclic groups

abstract:
  Consider a group G and an epimorphism u_0:G\to\Z inducing a splitting of G as
a semidirect product ker(u_0)\rtimes_\varphi\Z with ker(u_0) a finitely
generated free group and \varphi\in Out(ker(u_0)) representable by an expanding
irreducible train track map. Building on our earlier work [Dynamics on
free-by-cyclic groups, arXiv:1301.7739], in which we we realized G as \pi_1(X)
for an Eilenberg-Maclane 2-complex X equipped with a semiflow \psi, and
inspired by McMullen's Teichm\"uller polynomial for fibered hyperbolic
3-manifolds, we construct a polynomial invariant \m for (X,\psi) and
investigate its properties.
  Specifically, \m determines a convex polyhedral cone \C_X in H^1(G;\R), a
convex, real-analytic function \H:\C_X\to\R, and specializes to give an
integral Laurent polynomial \m_u(\zeta) for each integral u\in\C_X. We show
that \C_X is equal to the "cone of sections" of (X,\psi) (the convex hull of
all cohomology classes dual to sections of of \psi), and that for each
(compatible) cross section \Theta_u with first return map
f_u:\Theta_u\to\Theta_u, the specialization \m_u(\zeta) encodes the
characteristic polynomial of the transition matrix of f_u. More generally, for
every class u\in\C_X there exists a geodesic metric d_u and a codimension-1
foliation \Omega_u of X transverse to \psi so that after reparametrizing the
flow \psi^u_s maps leaves of \Omega_u to leaves via a local
e^{s\H(u)}-homothety.
  Among other things, we additionally prove that \C_X is equal to (the cone
over) the component of the BNS-invariant containing u_0 and that each primitive
integral u\in\C_X induces a splitting of G as an ascending HNN-extension over a
finite-rank free group along an injective endomorphism \phi_u. For any such
splitting, we show that the stretch factor of \phi_u is exactly given by
e^{\H(u)}. In particular, we see that \C_X and \H depend only on the group G
and epimorphism u_0.


title: Primordial non-Gaussianity in the bispectra of large-scale structure

abstract:
  The statistics of large-scale structure in the Universe can be used to probe
non-Gaussianity of the primordial density field, complementary to existing
constraints from the cosmic microwave background. In particular, the scale
dependence of halo bias, which affects the halo distribution at large scales,
represents a promising tool for analyzing primordial non-Gaussianity of local
form. Future observations, for example, may be able to constrain the
trispectrum parameter gNL that is difficult to study and constrain using the
CMB alone. We investigate how galaxy and matter bispectra can distinguish
between the two non-Gaussian parameters fNL and gNL, whose effects give nearly
degenerate contributions to the power spectra. We use a generalization of the
univariate bias approach, making the hypothesis that the number density of
halos forming at a given position is a function of the local matter density
contrast and of its local higher-order statistics. Using this approach, we
calculate the halo-matter bispectra and analyze their properties. We determine
a connection between the sign of the halo bispectrum on large scales and the
parameter gNL. We also construct a combination of halo and matter bispectra
that is sensitive to fNL, with little contamination from gNL. We study both the
case of single and multiple sources to the primordial gravitational potential,
discussing how to extend the concept of stochastic halo bias to the case of
bispectra. We use a specific halo mass-function to calculate numerically the
bispectra in appropriate squeezed limits, confirming our theoretical findings.


title: Confirmation of the planet around HD 95086 by direct imaging

abstract:
  VLT/NaCo angular differential imaging at L' (3.8 microns) revealed a probable
giant planet comoving with the young and early-type HD 95086 also known to
harbor an extended debris disk. The discovery was based on the proper motion
analysis of two datasets spanning 15 months. However, the second dataset
suffered from bad atmospheric conditions, which limited the significance of the
redetection at the 3 sigma level. In this Letter, we report new VLT/NaCo
observations of HD 95086 obtained on 2013 June 26-27 at L' to recover the
planet candidate. We unambiguously redetect the companion HD 95086 b with
multiple independent pipelines at a signal-to-noise ratio greater than or equal
to 5. Combined with previously reported measurements, our astrometry decisively
shows that the planet is comoving with HD 95086 and inconsistent with a
background object. With a revised mass of 5 pm 2 Jupiter masses, estimated from
its L' photometry and "hot-start" models at 17 pm 4 Myr, HD 95086 b becomes a
new benchmark for further physical and orbital characterization of young giant
planets.


title: Multigraded Betti numbers of simplicial forests

abstract:
  We prove that multigraded Betti numbers of a simplicial forest are always
either 0 or 1. Moreover a nonzero multidegree appears exactly at one
homological degree in the resolution. Our work generalizes work of Bouchat on
edge ideals of graph forests.


title: Color Differences between Clockwise and Counterclockwise Spiral Galaxies

abstract:
  While spiral galaxies observed from Earth clearly seem to spin in different
directions, little is yet known about other differences between galaxies that
spin clockwise and galaxies that spin counterclockwise. Here we compared the
color of 64,399 spiral galaxies that spin clockwise to 63,215 spiral galaxies
that spin counterclockwise. The results show that clockwise galaxies tend to be
bluer than galaxies that spin counterclockwise. The probability that the color
differences can be attributed to chance is ~0.019.


title:
Quantum walk with a general coin: Exact solution and asymptotic
  properties

abstract:
  In this paper we present closed-form expressions for the wave function that
governs the evolution of the discrete-time quantum walk on a line when the coin
operator is arbitrary. The formulas were derived assuming that the walker can
either remain put in the place or proceed in a fixed direction but never move
backward, although they can be easily modified to describe the case in which
the particle can travel in both directions. We use these expressions to explore
the properties of magnitudes associated to the process, as the probability mass
function or the probability current, even though we also consider the
asymptotic behavior of the exact solution. Within this approximation, we will
estimate upper and lower bounds, consider the origins of an emerging
approximate symmetry, and deduce the general form of the stationary probability
density of the relative location of the walker.

categories: quant-ph cond-mat.stat-mech math-ph math.MP


title: On the quantum stability of Q-balls

abstract:
  We consider the evolution and decay of Q-balls under the influence of quantum
fluctuations. We argue that the most important effect resulting from these
fluctuations is the modification of the effective potential in which the Q-ball
evolves. This is in addition to spontaneous decay into elementary particle
excitations and fission into smaller Q-balls previously considered in the
literature, which -- like most tunnelling processes -- are likely to be
strongly suppressed. We illustrate the effect of quantum fluctuations in a
particular model $\phi^6$ potential, for which we implement the inhomogeneous
Hartree approximation to quantum dynamics and solve for the evolution of
Q-balls in 3+1 dimensions. We find that the stability range as a function of
(field space) angular velocity $\omega$ is modified significantly compared to
the classical case, so that small-$\omega$ Q-balls are less stable than in the
classical limit, and large-$\omega$ Q-balls are more stable. This can be
understood qualitatively in a simple way.


title:
Turbulence patterns and neutrino flavor transitions in high-resolution
  supernova models

abstract:
  During the shock-wave propagation in a core-collapse supernova (SN), matter
turbulence may affect neutrino flavor conversion probabilities. Such effects
have been usually studied by adding parametrized small-scale random
fluctuations (with arbitrary amplitude) on top of coarse, spherically symmetric
matter density profiles. Recently, however, two-dimensional (2D) SN models have
reached a space resolution high enough to directly trace anisotropic density
profiles, down to scales smaller than the typical neutrino oscillation length.
In this context, we analyze the statistical properties of a large set of SN
matter density profiles obtained in a high-resolution 2D simulation, focusing
on a post-bounce time (2 s) suited to study shock-wave effects on neutrino
propagation on scales as small as O(100) km and possibly below. We clearly find
the imprint of a broken (Kolmogorov-Kraichnan) power-law structure, as
generically expected in 2D turbulence spectra. We then compute the flavor
evolution of SN neutrinos along representative realizations of the turbulent
matter density profiles, and observe no or modest damping of the neutrino
crossing probabilities on their way through the shock wave. In order to check
the effect of possibly unresolved fluctuations at scales below O(100) km, we
also apply a randomization procedure anchored to the power spectrum calculated
from the simulation, and find consistent results within \pm 1 sigma
fluctuations. These results show the importance of anchoring turbulence effects
on SN neutrinos to realistic, fine-grained SN models.


title:
Parallel Magnetic Resonance Imaging as Approximation in a Reproducing
  Kernel Hilbert Space

abstract:
  In Magnetic Resonance Imaging (MRI) data samples are collected in the spatial
frequency domain (k-space), typically by time-consuming line-by-line scanning
on a Cartesian grid. Scans can be accelerated by simultaneous acquisition of
data using multiple receivers (parallel imaging), and by using more efficient
non-Cartesian sampling schemes. As shown here, reconstruction from samples at
arbitrary locations can be understood as approximation of vector-valued
functions from the acquired samples and formulated using a Reproducing Kernel
Hilbert Space (RKHS) with a matrix-valued kernel defined by the spatial
sensitivities of the receive coils. This establishes a formal connection
between approximation theory and parallel imaging. Theoretical tools from
approximation theory can then be used to understand reconstruction in k-space
and to extend the analysis of the effects of samples selection beyond the
traditional g-factor noise analysis to both noise amplification and
approximation errors. This is demonstrated with numerical examples.


title: Crystallizing hard-sphere glasses by doping with active particles

abstract:
  Crystallization and vitrification are two different routes to form a solid.
Normally these two processes suppress each other, with the glass transition
preventing crystallization at high density (or low temperature). This is even
true for systems of colloidal hard spheres, which are commonly used as building
blocks for novel functional materials with potential applications, e.g.
photonic crystals. By performing Brownian dynamics simulations of glassy
systems consisting of mixtures of active and passive hard spheres, we show that
the crystallization of such hard-sphere glasses can be dramatically promoted by
doping the system with small amounts of active particles. Surprisingly, even
hard-sphere glasses of packing fraction up to $\phi = 0.635$ crystallize, which
is around $0.5\%$ below the random close packing at $\phi \simeq 0.64$. Our
results suggest a novel way of fabricating crystalline materials from
(colloidal) glasses. This is particularly important for materials that get
easily kinetically trapped in glassy states, and crystal nucleation hardly
occurs.


title:
Large enhancement of Forster resonance energy transfer on graphene
  platforms

abstract:
  In the view of the applications of Forster resonant energy transfer (FRET) in
biological systems which especially require FRET in the inrared region we
investigate the great advantage of graphene plasmonics in such studies.
Focusing on the fundamental aspects of FRET between a donor-acceptor pair on a
graphene platform showing that FRET mediated by the plasmons in graphene is
broadband and enhanced by six orders of magnitude. We briefly discuss the
impact of phonon-polaritonic substrates.


title: A coronal wave as CME footprint

abstract:
  I report a coronal wave observed in Fexii, soft X-ray, and Halpha on November
6, 2006, jointly with a CME and a flare to show the spatial and temporal
relation of the wave and the CME. I also take advantage of the spectral
resolution of the wave to obtain an approximation of its temperature. Finally,
I compare the magnetic field topology to the wave location. The observations in
two band passes show bright fronts that are co-spatial when observed at the
same time, therefore I believe that the same wave is observed in different band
passes. The wave front is not observable in Halpha, but just in Fexii and in
soft X-ray, indicating that the temperature of the wave front is slightly
higher than the chromospheric temperature. The ratio of emission through two
SXI filters gives a temperature of 7 10^6 K for the wave front. The
northern-most edge of the CME footprint related to this wave corresponds to the
last location of the wave on the limb. The image processing reveals stationary
brightenings produced on the passage of the wave front. The potential spherical
extrapolation of the sun shows that those stationary brightenings are lying in
jumps of magnetic field lines connectivity.


title: The merging cluster of galaxies Abell 3376: an optical view

abstract:
  Abell 3376 is a merging cluster of galaxies at redshift z=0.046, famous
mostly for its giant radio arcs, and shows an elongated and highly
substructured X-ray emission, but has not been analysed in detail at optical
wavelengths. We have obtained wide field images of Abell 3376 in the B band and
derive the GLF applying a statistical subtraction of the background in three
regions: a circle of 0.29 deg radius (1.5 Mpc) encompassing the whole cluster,
and two circles centered on each of the two brightest galaxies (BCG2,
northeast, coinciding with the peak of X-ray emission, and BCG1, southwest) of
radii 0.15 deg (0.775 Mpc). We also compute the GLF in the zone around BCG1,
which is covered by the WINGS survey in the B and V bands, by selecting cluster
members in the red sequence in a (B-V) versus V diagram. Finally, we discuss
the dynamical characteristics of the cluster implied by a Serna & Gerbal
analysis. The GLFs are not well fit by a single Schechter function, but
satisfactory fits are obtained by summing a Gaussian and a Schechter function.
The GLF computed by selecting galaxies in the red sequence in the region
surrounding BCG1 can also be fit by a Gaussian plus a Schechter function. An
excess of galaxies in the brightest bins is detected in the BCG1 and BCG2
regions. The dynamical analysis based on the Serna & Gerbal method shows the
existence of a main structure of 82 galaxies which can be subdivided into two
main substructures of 25 and 6 galaxies. A smaller structure of 6 galaxies is
also detected. The B band GLFs of Abell 3376 are clearly perturbed, as already
found in other merging clusters. The dynamical properties are consistent with
the existence of several substructures, in agreement with a previously
published X-ray analysis.


title: Isaac Newton's sinister heraldry

abstract:
  After Isaac Newton was knighted by Queen Anne in 1705 he adopted an unusual
coat of arms: a pair of human tibiae crossed on a black background, like a
pirate flag without the skull. After some general reflections on Newton's
monumental scientific achievements and on his enigmatic life, we investigate
the story of his coat of arms. We also discuss how its simple design
illustrates the concept of chirality, which would later play an important role
in the philosophical arguments about Newton's conception of space, as well as
in the development of modern chemistry and particle physics.


title: Hypercharged Dark Matter and Direct Detection as a Probe of Reheating

abstract:
  The lack of new physics at the LHC so far weakens the argument for TeV scale
thermal dark matter. On the other hand, heavier, non-thermal dark matter is
generally difficult to test experimentally. Here we consider the interesting
and generic case of hypercharged dark matter, which can allow for heavy dark
matter masses without spoiling testability. Planned direct detection
experiments will be able to see a signal for masses up to an incredible
$10^{10}$ GeV, and this can further serve to probe the reheating temperature up
to about $10^9$ GeV, as determined by the non-thermal dark matter relic
abundance. The $Z$-mediated nature of the dark matter scattering may be
determined in principle by comparing scattering rates on different detector
nuclei, which in turn can reveal the dark matter mass. We will discuss the
extent to which future experiments may be able to make such a determination.


title:
Recollision scenario without tunneling : Role of the ionic core
  potential

abstract:
  The standard model of strong laser physics, the recollision scenario, omits
the ionic core potential after tunneling. Strikingly, although the Coulomb
interaction drives all stages of recollision, the maximum energy the electrons
bring back to the core is found by ignoring it. We resolve this long-standing
paradox by showing that this good agreement stems from a fortuitous
cancellation at high intensities. Instead of the three step model, we find that
the Coulomb interaction can be fully integrated into a purely classical
scenario that explains recollisions without invoking tunneling.


title:
Shock-induced $\mathcal{PT}$-symmetric potentials in gas-filled photonic
  crystal fibers

abstract:
  We have investigated the interaction between a strong soliton and a weak
probe with certain configurations that allow optical trapping in gas-filled
hollow-core photonic crystal fibers in the presence of the shock effect. We
have shown theoretically and numerically that the shock term can lead to an
unbroken parity-time $ \left(\mathcal{PT}\right) $ symmetry potential in these
kinds of fibers. Reciprocity breaking, a remarkable feature of the $
\mathcal{PT} $ symmetry, is also demonstrated numerically. Our results will
open different configurations and avenues for observing $ \mathcal{PT}
$-symmetry breaking in optical fibers, without the need to resort to cumbersome
dissipative structures.