title:
The Coherent Interlayer Resistance of a Single, Rotated Interface
  between Two Stacks of AB Graphite

abstract:
  The coherent, interlayer resistance of a misoriented, rotated interface
between two stacks of AB graphite is determined for a variety of misorientation
angles. The quantum-resistance of the ideal AB stack is on the order of 1 to 10
m$\Omega \mu{\rm m}^2$. For small rotation angles, the coherent interlayer
resistance exponentially approaches the ideal quantum resistance at energies
away from the charge neutrality point. Over a range of intermediate angles, the
resistance increases exponentially with cell size for minimum size unit cells.
Larger cell sizes, of similar angles, may not follow this trend. The energy
dependence of the interlayer transmission is described.


title:
The epigenome of evolving Drosophila neo-sex chromosomes: dosage
  compensation and heterochromatin formation

abstract:
  Drosophila Y chromosomes are composed entirely of silent heterochromatin,
while male X chromosomes have highly accessible chromatin and are
hypertranscribed due to dosage compensation. Here, we dissect the molecular
mechanisms and functional pressures driving heterochromatin formation and
dosage compensation of the recently formed neo-sex chromosomes of Drosophila
miranda. We show that the onset of heterochromatin formation on the neo-Y is
triggered by an accumulation of repetitive DNA. The neo-X has evolved partial
dosage compensation and we find that diverse mutational paths have been
utilized to establish several dozen novel binding consensus motifs for the
dosage compensation complex on the neo-X, including simple point mutations at
pre-binding sites, insertion and deletion mutations, microsatellite expansions,
or tandem amplification of weak binding sites. Spreading of these silencing or
activating chromatin modifications to adjacent regions results in massive
mis-expression of neo-sex linked genes, and little correspondence between
functionality of genes and their silencing on the neo-Y or dosage compensation
on the neo-X. Intriguingly, the genomic regions being targeted by the dosage
compensation complex on the neo-X and those becoming heterochromatic on the
neo-Y show little overlap, possibly reflecting different propensities along the
ancestral chromosome to adopt active or repressive chromatin configurations.
Our findings have broad implications for current models of sex chromosome
evolution, and demonstrate how mechanistic constraints can limit evolutionary
adaptations. Our study also highlights how evolution can follow predictable
genetic trajectories, by repeatedly acquiring the same 21-bp consensus motif
for recruitment of the dosage compensation complex, yet utilizing a diverse
array of random mutational changes to attain the same phenotypic outcome.


title:
A variational formulation of electrostatics in a medium with spatially
  varying dielectric permittivity

abstract:
  In biological and synthetic materials, many important processes involve
charges that are present in a medium with spatially varying dielectric
permittivity. To accurately understand the role of electrostatic interactions
in such systems, it is important to take into account the spatial dependence of
the permittivity of the medium. However, due to the ensuing theoretical and
computational challenges, this inhomogeneous dielectric response of the medium
is often ignored or excessively simplified. We develop a variational
formulation of electrostatics to accurately investigate systems that exhibit
this inhomogeneous dielectric response. Our formulation is based on a true
energy functional of the polarization charge density. The defining
characteristic of a true energy functional is that at its minimum it evaluates
to the actual value of the energy; this is a feature not found in many commonly
used electrostatic functionals. We explore in detail the charged systems that
exhibit sharp discontinuous change in dielectric permittivity, and we show that
for this case our functional reduces to a functional of only the surface
polarization charge density. We apply this reduced functional to study model
problems for which analytical solutions are well known. We demonstrate, in
addition, that the functional has many properties that make it ideal for use in
molecular dynamics simulations.


title: Superconducting single-photon detector made of MoSi film

abstract:
  We fabricated and characterised nanowire superconducting single-photon
detectors (SSPDs) made of 4 nm thick amorphous Mo$_x$Si$_{1-x}$ films. At 1.7 K
the best devices exhibit a detection efficiency up to 18% at 1.2 um wavelength
of unpolarised light, a characteristic response time of about 6 ns and timing
jitter of 120 ps. The detection efficiency was studied in wavelength range from
650 nm to 2500 nm. At wavelengths below 1200 nm these detectors reach their
maximum detection efficiency limited by photon absorption in the thin MoSi
film.


title: Looking at the photoproduction of massive gauge bosons at the LHeC

abstract:
  In this contribution we report on the investigation of the photoproduction of
W and Z bosons in the planned electron-proton/nucleus collider, the LHeC. The
production cross sections and the number of events are provided and theoretical
uncertainties are discussed. We also analyze the sensitivity of the LHeC
experiment to physics beyond Standard Model by studying the role played by
anomalous WWgamma coupling in the presented process.


title:
Generalized Amitsur-Levitski theorem and equations for sheets in a
  reductive complex Lie algebra

abstract:
  I connect an old result of mine on a Lie algebra generalization of the
Amitsur-Levitski theorem with equations for sheets in a reductive Lie algebra
and with recent results of Kostant-Wallach on the variety of singular elements
in a reductive Lie algebra.


abstract:
  Discovery of a Higgs boson and precise measurements of its properties open a
new window to test physics beyond the standard model. Models with Universal
Extra Dimensions are not exception. Kaluza-Klein excitations of the standard
model particles contribute to the production and decay of the Higgs boson. In
particular, the parameters associated with third generation quarks are
constrained by Higgs data, which are relatively insensitive to other searches
often involving light quarks and leptons. We investigate implications of the
126 GeV Higgs in Next-to-Minimal Universal Extra Dimensions, and show that
boundary terms and bulk masses allow a lower compactification scale as compared
to in Minimal Universal Extra Dimensions.


title:
Thermally populated intrinsic localized modes in pure alkali halide
  crystals

abstract:
  The possibility of thermal excitation of intrinsic localized modes (ILMs)
arising from anharmonicity in ionic perfect crystals is studied numerically for
realistic model systems in one and three dimensions. Implications are discussed
for an interesting high-temperature feature seen in earlier inelastic neutron
scattering experiments on single crystal NaI. The general conclusion is that
ILM formation energies are far too large for thermal excitation of ILMs to
account for the observed feature in a pure crystal.


title:
Influence of nanoscale temperature rises on photoacoustic generation:
  discrimination between optical absorbers based on nonlinear photoacoustics at
  high frequency

abstract:
  In the thermoelastic regime, photoacoustic sensing of optical absorption
relies on conversion from light to acoustic energy via the coefficient of
thermal expansion \beta. In this work, we confront confront experimental
measurements to theoretical predictions of nonlinear photoacoustic generation
based on the dynamic variation of \beta(T) during the optical excitation of
absorbers in aqueous solution. The photoacoustic generation from solutions of
organic dye and gold nanospheres (with same optical densities), illuminated
with 532 nm nanosecond pulses, was detected using a high frequency ultrasound
transducer (center frequency 20 MHz). Photoacoustic emission was observed with
gold nanospheres at low fluence (a few mJ/cm2) for an equilibrium temperature
around 4{\deg}C, where the linear photoacoustic effect in water vanishes,
highlighting the nonlinear emission from the solution of nanospheres. Under the
same condition, no emission was observed with the absorbing organic dye. At a
fixed fluence of 5 mJ/cm2, the photoacoustic amplitude was studied as a
function of the equilibrium temperature from 2{\deg}C to 20{\deg}C. While the
photoacoustic amplitude from the organic dye followed \beta(T) in water and
vanished around 4{\deg}C, the photoacoustic amplitude from the gold nanospheres
remained significant over the whole temperature range. These experimental
results are shown to be in qualitative agreement with theoretical calculations
based on the nanoscale and nanosecond transient changes of the coefficient of
thermal expansion of water around the gold nanospheres. Our results suggest
that in the context of high frequency photoacoustic imaging, nanoparticles may
be discriminated from molecular absorbers based on either the nonlinear
fluence-dependence or the equilibrium temperature-dependence of the
photoacoustic amplitude.


title:
Neutrino production from photo-hadronic interactions of the gamma flux
  from Active Galactic Nuclei with their gas content

abstract:
  The diffuse neutrino flux from FRI and BL Lac type galaxies generated from
interactions of their own gamma radiation with the gas and dust at the sources
is reported. This neutrino-production channel has not been studied in detail up
to now. The calculations are based on individual estimations of the neutrino
flux in two nearby AGN's: Centaurus A and M87, assuming the validity of the AGN
unification model. The predictions for Centaurus A and M87 involved the
parameterization of the measured gamma-ray luminosities and the modeling of the
material of the galaxies both based on observations performed by several
detectors. No hadronic origin for the TeV photons is assumed. The results show
that, although the corresponding neutrino flux ($E^{2} \Phi_{\nu + \bar{\nu}} <
10^{-13} s^{-1} sr^{-1} GeV cm^{-2}$) is not competitive at high-energies
($E_\nu > 1 TeV$) with that from hadronic models, FRI and BL Lac galaxies with
gamma emission should be already contributing to the diffuse flux of neutrinos
in the universe.


title:
Using diffuse radio emission in clusters of galaxies to probe the cosmic
  web, cosmic rays and dark matter

abstract:
  The study of diffuse radio sources is essential to our knowledge of the
physical conditions in clusters of galaxies and of the role that large scale
magnetic fields play in the propagation of the relativistic particles in the
intracluster medium (ICM). Due to dissipative processes, the thermal plasma of
the ICM contains useless information about the formation of structures and CRs.
Such past and current information is carried intact by its non-thermal emission
caused by highly relativistic particles spiraling in large-scale magnetic
fields. The diffuse radio emission is not associated with the active galactic
nucleus phenomenon and has no optical counterpart. Instead it is associated
with the ICM and it is characterized by steep spectrum. The low surface radio
brightness features are thought to be formed via re-acceleration of a relic
population of relativistic electrons, or proton-proton collisions with the ICM.
Diffuse radio sources are classified typically as `relics', `halos',
'mini-halos' and 'radio-ghosts'. We use a sample of 67 nearby clusters of
galaxies at redshift, 0.02 < z < 0.1, to tackle the relation between the
diffuse radio emission and the large scale structure (cosmic web), dark matter
(DM) and cosmic rays (CRs). Our sample of clusters at low redshift containing
areas of radio flux below the Jy level is well suited for the study of DM. DM
halos can substantially contribute to the counts of sources at low brightness.
We report on the work in progress.


title:
A Cache Reconfiguration Approach for Saving Leakage and Refresh Energy
  in Embedded DRAM Caches

abstract:
  In recent years, the size and leakage energy consumption of large last level
caches (LLCs) has increased. To address this, embedded DRAM (eDRAM) caches have
been considered which have lower leakage energy consumption; however eDRAM
caches consume a significant amount of energy in the form of refresh energy. In
this paper, we present a technique for saving both leakage and refresh energy
in eDRAM caches. We use dynamic cache reconfiguration approach to intelligently
turn-off part of the cache to save leakage energy and refresh only valid data
of the active (i.e. not turned-off) cache to save refresh energy. We evaluate
our technique using an x86-64 simulator and SPEC2006 benchmarks and compare it
with a recently proposed technique for saving refresh energy, named Refrint.
The experiments have shown that our technique provides better performance and
energy efficiency than Refrint. Using our technique, for a 2MB LLC and 40
micro-seconds eDRAM refresh period, the average saving in energy over eDRAM
baseline (which periodically refreshes all cache lines) is 22.8%.


title:
Characterization of EASIROC as Front-End for the readout of the SiPM at
  the focal plane of the Cherenkov telescope ASTRI

abstract:
  The Extended Analogue Silicon Photo-multiplier Integrated Read Out Chip,
EASIROC, is a chip proposed as front-end of the camera at the focal plane of
the imaging Cherenkov ASTRI SST-2M telescope prototype. This paper presents the
results of the measurements performed to characterize EASIROC in order to
evaluate its compliance with the ASTRI SST-2M focal plane requirements. In
particular, we investigated the trigger time walk and the jitter effects as a
function of the pulse amplitude. The EASIROC output signal is found to vary
linearly as a function of the input pulse amplitude with very low level of
electronic noise and cross-talk (<1%). Our results show that it is suitable as
front-end chip for the camera prototype, although, specific modifications are
necessary to adopt the device in the final version of the telescope.


title: How good is the Chord algorithm?

abstract:
  The Chord algorithm is a popular, simple method for the succinct
approximation of curves, which is widely used, under different names, in a
variety of areas, such as, multiobjective and parametric optimization,
computational geometry, and graphics. We analyze the performance of the Chord
algorithm, as compared to the optimal approximation that achieves a desired
accuracy with the minimum number of points. We prove sharp upper and lower
bounds, both in the worst case and average case setting.


title:
Self-Organizing Maps Parametrization of Deep Inelastic Structure
  Functions with Error Determination

abstract:
  We present and discuss a new method to extract parton distribution functions
from hard scattering processes based on an alternative type of neural network,
the Self-Organizing Map. Quantitative results including a detailed treatment of
uncertainties are presented within a Next to Leading Order analysis of
inclusive electron proton deep inelastic scattering data.


title:
Triply Extended Group of Translations of $\mathbb{R}^{4}$ as Defining
  Group of NCQM: relation to various gauges

abstract:
  The role of the triply extended group of translations of $\mathbb{R}^{4}$, as
the defining group of two dimensional noncommutative quantum mechanics (NCQM),
has been studied in \cite{ncqmjmp}. In this paper, we revisit the coadjoint
orbit structure and various irreducible representations of the group associated
with them. The two irreducible representations corresponding to the Landau and
symmetric gauges are found to arise from the underlying defining group. The
group structure of the transformations, preserving the commutation relations of
NCQM, has been studied along with specific examples. Finally, the relationship
of a certain family of UIRs of the underlying defining group with a family of
deformed complex Hermite polynomials has been explored .


title:
Free-energy functionals of the electrostatic potential for
  Poisson-Boltzmann theory

abstract:
  In simulating charged systems, it is often useful to treat some ionic
components of the system at the mean-field level and solve the
Poisson-Boltzmann (PB) equation to get their respective density profiles. The
numerically intensive task of solving the PB equation at each step of the
simulation can be bypassed using variational methods that treat the
electrostatic potential as a dynamic variable. But such approaches require the
access to a true free-energy functional; a functional that not only provides
the correct solution of the PB equation upon extremization, it also evaluates
to the true free energy of the system at its minimum. Moreover, the numerical
efficiency of such procedures is further enhanced if the free-energy functional
is local and is expressed in terms of the electrostatic potential. Existing PB
functionals of the electrostatic potential, while possessing the local
structure, are not free-energy functionals. We present a variational
formulation with a local free-energy functional of the potential. In addition,
we also construct a nonlocal free-energy functional of the electrostatic
potential. These functionals are suited for employment in simulation schemes
based on the ideas of dynamical optimization.


title: Szego kernels and Poincare series

abstract:
  Let $M = \tilde{M}/\Gamma$ be a Kahler manifold, where $\tilde{M}$ is the
universal Kahler cover, and where $\Gamma$ is the deck transformation group.
Let $(L, h) \to M$ be a positive Hermitian holomorophic line bundle. Lift the
Hermitian line bundle to $\tilde{M}$ and consider the relation between the
orthogonal projection onto holomorphic sections on the quotient and onto $L^2$
holomorphic sections on $\tilde{M}$. We prove that the quotient Szego kernel is
given by the periodization of the $L^2$ Szego kernel of the universal cover,
i.e. its sum over the deck group $\Gamma$. Although this is a standard result
for symmetric spaces (it is used in the Selberg trace formula) and is also
standard for heat and wave kernels, it seems that a proof of the sum over Gamma
formula was lacking for Szego kernels of positive line bundles over general
Kahler manifolds.
  We apply the result to give a simple proof of Napier's theorem on the
holomorphic convexity of $\tilde{M}$ with respect to $\tilde{L}^N$ and to
surjectivity of Poincar\'e series. We also simplify the discussion of Poincare
series in Kollar's book.


title:
Generating true minima in constrained variational formulations via
  modified Lagrange multipliers

abstract:
  Variational principles are important in the investigation of large classes of
physical systems. They can be used both as analytical methods as well as
starting points for the formulation of powerful computational techniques such
as dynamical optimization methods. Systems with charged objects in dielectric
media and systems with magnetically active particles are important examples. In
these examples and other important cases, the variational principles describing
the system are required to obey a number of constraints. These constraints are
implemented within the variational formulation by means of Lagrange
multipliers. Such constrained variational formulations are in general not
unique. For the application of efficient simulation methods, one must find
specific formulations that satisfy a number of important conditions. An often
required condition is that the functional be positive-definite, in other words,
its extrema be actual minima. In this article, we present a general approach to
attack the problem of finding, among equivalent variational functionals, those
that generate true minima. The method is based on the modification of the
Lagrange multiplier which allows us to generate large families of effective
variational formulations associated with a single original constrained
variational principle. We demonstrate its application to different examples
and, in particular, to the important cases of Poisson and Poisson-Boltzmann
equations. We show how to obtain variational formulations for these systems
with extrema that are always minima.

categories: cond-mat.soft math-ph math.MP physics.class-ph


title: Implosion of coronal loops during the impulsive phase of a solar flare

abstract:
  We study the relationship between implosive motions in a solar flare, and the
energy redistribution in the form of oscillatory structures and particle
acceleration. The flare SOL2012-03-09T03:53 (M6.4) shows clear evidence for an
irreversible (stepwise) coronal implosion. Extreme-ultraviolet (EUV) images
show at least four groups of coronal loops at different heights overlying the
flaring core undergoing fast contraction during the impulsive phase of the
flare. These contractions start around a minute after the flare onset, and the
rate of contraction is closely associated with the intensity of the hard X-ray
(HXR) and microwave emissions. They also seem to have a close relationship with
the dimming associated with the formation of the Coronal Mass Ejection (CME)
and a global EUV wave. Several studies now have detected contracting motions in
the corona during solar flares that can be interpreted as the implosion
necessary to release energy. Our results confirm this, and tighten the
association with the flare impulsive phase. We add to the phenomenology by
noting the presence of oscillatory variations revealed by GOES soft X-rays
(SXR) and spatially-integrated EUV emission at 94 and 335 {\AA}. We identify
pulsations of $\approx 60$ seconds in SXR and EUV data, which we interpret as
persistent, semi-regular compressions of the flaring core region which modulate
the plasma temperature and emission measure. The loop oscillations, observed
over a large region, also allow us to provide rough estimates of the energy
temporarily stored in the eigenmodes of the active-region structure as it
approaches its new equilibrium.


title:
Infinite Dimensional Choi-Jamiolkowski States and Time Reversed Quantum
  Markov Semigroups

abstract:
  We propose a definition of infinite dimensional Choi-Jamiolkowski state
associated with a completely positive trace preserving map. We introduce the
notion of Theta-KMS adjoint of a quantum Markov semigroup, which is identified
with the time reversed semigroup. The break down of Theta-KMS symmetry (or
Theta-standard quantum detailed balance in the sense of Fagnola-Umanita) is
measured by means of the von Neumann relative entropy of the Choi-Jamiolkowski
states associated with the semigroup and its Theta-KMS adjoint.


title:
Generating Anisotropic Collapse and Expansion Solutions of Einstein's
  Equations

abstract:
  Analytic gravitational collapse and expansion solutions with anisotropic
pressure are generated. Metric functions are found by requiring zero heat flow
scalar. It emerges that a single function generates the anisotropic solutions.
Each generating function contains an arbitrary function of time which can be
chosen to fit various astrophysical time profiles. Two examples are provided: a
bounded collapse metric and an expanding cosmological solution


title:
Project 8: Determining neutrino mass from tritium beta decay using a
  frequency-based method

abstract:
  A general description is given of Project 8, a new approach to measuring the
neutrino mass scale via the beta decay of tritium. In Project 8, the energy of
electrons emitted in beta decay is determined from the frequency of cyclotron
radiation emitted as the electrons spiral in a uniform magnetic field.


title:
Elliptic Ding-Iohara Algebra and Commutative Families of the Elliptic
  Macdonald Operator

abstract:
  The elliptic Ding-Iohara algebra is an elliptic quantum group obtained from
the free field realization of the elliptic Macdonald operator. In this article,
we show the construction of two families of commuting operators which contain
the elliptic Macdonald operator by using the elliptic Ding-Iohara algebra and
the elliptic Feigin-Odesskii algebra.


title:
Air shower registration algorithm and mathematical processing of showers
  with radio signal at the Yakutsk array

abstract:
  The paper describes the techniques and method of registration of air shower
radio emission at the Yakutsk array of extensive air showers at a frequency of
32 MHz. At this stage, emission registration involves two set of antennas, the
distance between them is 500m. One set involves 8 antennas, second - 4
antennas. The antennas are perpendicularly crossed dipoles with radiation
pattern North South,West East and raised 1.5 m above the ground. Each set of
antennas connected to an industrial PC. The registration requires one of two
triggers. First trigger are generated by scintillation detectors of Yakutsk
array. Scintillation detectors cover area of 12 km^2 and registers air showers
with energy more than 10^17 eV. The second trigger is generated by Small
Cherenkov Array that covers area of 1 km^2 and registers air showers with
energy 10^15 - 5*10^17 eV. Small Cherenkov Array is part of Yakutsk array and
involve Cherenkov detectors located at a distance of 50, 100, 250 m. For
further selection we are using an additional criterion the radio pulse must be
localized in the area corresponding to the delay time on first and second
triggers. In addition, descriptions of the algorithm and the flowcharts of the
program for the air shower selection and further analysis are given. This
method registers EAS radio emission with energy 10^16 - 10^19 eV. With the
absolute calibration, the amplitudes of all antennas converted to a single
value. Air shower radio emission dependences from zenith angle and shower
energy are plotted.


title: A Note on Gluing Dirac Type Operators on a Mirror Quantum Two-Sphere

abstract:
  The goal of this paper is to introduce a class of operators, which we call
quantum Dirac type operators on a noncommutative sphere, by a gluing
construction from copies of noncommutative disks, subject to an appropriate
local boundary condition. We show that the resulting operators have compact
resolvents, and so they are elliptic operators.


title:
Influence of Stellar Multiplicity On Planet Formation. I. Evidence of
  Suppressed Planet Formation Due to Stellar Companions Within 20 AU and
  Validation of Four Planets From the Kepler Multiple Planet Candidates

abstract:
  The planet occurrence rate for multiple stars is important in two aspects.
First, almost half of stellar systems in the solar neighborhood are multiple
systems. Second, the comparison of the planet occurrence rate for multiple
stars to that for single stars sheds light on the influence of stellar
multiplicity on planet formation and evolution. We developed a method of
distinguishing planet occurrence rates for single and multiple stars. From a
sample of 138 bright (KP <13.5) Kepler multi-planet candidate systems, we
compared the stellar multiplicity rate of these planet host stars to that of
field stars. Using dynamical stability analyses and archival Doppler
measurements, we find that the stellar multiplicity rate of planet host stars
is significantly lower than field stars for semi-major axes less than 20 AU,
suggesting that planet formation and evolution are suppressed by the presence
of a close-in companion star at these separations. The influence of stellar
multiplicity at larger separations is uncertain because of search in-
completeness due to a limited Doppler observation time baseline and a lack of
high resolution imaging observation. We calculated the planet confidence for
the sample of mutlti-planet candidates, and find that the planet confidences
for KOI 82.01, KOI 115.01, KOI 282.01 and KOI 1781.02 are higher than 99.7% and
thus validate the planetary nature of these four planet candidates. This sample
of bright Kepler multi-planet candidates with refined stellar and orbital
parameters, planet confidence estimation, and nearby stellar companion
identification offers a well-characterized sample for future theoretical and
observational study.


title:
An Explicit Formulation of the Earth Movers Distance with Continuous
  Road Map Distances

abstract:
  The Earth movers distance (EMD) is a measure of distance between probability
distributions which is at the heart of mass transportation theory. Recent
research has shown that the EMD plays a crucial role in studying the potential
impact of Demand-Responsive Transportation (DRT) and Mobility-on-Demand (MoD)
systems, which are growing paradigms for one-way vehicle sharing where people
drive (or are driven by) shared vehicles from a point of origin to a point of
destination. While the ubiquitous physical transportation setting is the road
network, characterized by systems of roads connected together by interchanges,
most analytical works about vehicle sharing represent distances between points
in a plane using the simple Euclidean metric. Instead, we consider the EMD when
the ground metric is taken from a class of one-dimensional, continuous metric
spaces, reminiscent of road networks. We produce an explicit formulation of the
Earth movers distance given any finite road network R. The result generalizes
the EMD with a Euclidean R1 ground metric, which had remained one of the only
known non-discrete cases with an explicit formula. Our formulation casts the
EMD as the optimal value of a finite-dimensional, real-valued optimization
problem, with a convex objective function and linear constraints. In the
special case that the input distributions have piece-wise uniform (constant)
density, the problem reduces to one whose objective function is convex
quadratic. Both forms are amenable to modern mathematical programming
techniques.


title: On the Internal Dynamics of the Shanghai Ranking

abstract:
  The Academic Ranking of World Universities (ARWU) published by researchers at
Shanghai Jiao Tong University has become a major source of information for
university administrators, country officials, students and the public at large.
Recent discoveries regarding its internal dynamics allow the inversion of
published ARWU indicator scores to reconstruct raw scores for five hundred
world class universities. This paper explores raw scores in the ARWU and in
other contests to contrast the dynamics of rank-driven and score-driven tables,
and to explain why the ARWU ranking is a score-driven procedure. We show that
the ARWU indicators constitute sub-scales of a single factor accounting for
research performance, and provide an account of the system of gains and
non-linearities used by ARWU. The paper discusses the non-linearities selected
by ARWU, concluding that they are designed to represent the regressive
character of indicators measuring research performance. We propose that the
utility and usability of the ARWU could be greatly improved by replacing the
unwanted dynamical effects of the annual re-scaling based on raw scores of the
best performers.


title:
Unusual pressure effects on the superconductivity of indirectly
  electron-doped (Ba1-xLax)Fe2As2 epitaxial films

abstract:
  Applying an external pressure to indirectly electron-doped 122-type
(Ba1-xLax)Fe2As2 epitaxial films enhances the superconducting critical
temperature (Tc) up to 30.3 K. Different from the other family compounds, the
Tc is enhanced not only in the under-doped region but also in the optimally
doped and over-doped regions. Narrowing of the superconducting transition width
and an increase in the carrier density take place simultaneously in the whole
doping region, except at the heavily over-doped limit. This characteristic is
unique to and observed only in (Ba1-xLax)Fe2As2, in which the La doping is
stabilized via non-equilibrium growth of the vapor phase epitaxy, among the
122-type iron-based superconductors, AFe2As2 (A = Ba, Sr, and Ca).


title:
SO(2)-congruent projections of convex bodies with rotation about the
  origin

abstract:
  We prove that if two convex bodies $ K, L \subset \mathbb{R}^3$ satisfy the
property that the orthogonal projections of $K$ and $L$ onto every plane
containing the origin are roations of each other, then either $K$ and $L$
coincide or $L$ is the image of $K$ under a reflection about the origin


title: Finite Length Analysis of LDPC Codes

abstract:
  In this paper, we study the performance of finite-length LDPC codes in the
waterfall region. We propose an algorithm to predict the error performance of
finite-length LDPC codes over various binary memoryless channels. Through
numerical results, we find that our technique gives better performance
prediction compared to existing techniques.


title:
Degenerations of Complex Dynamical Systems II: Analytic and Algebraic
  Stability

abstract:
  We study pairs $(f, \Gamma)$ consisting of a non-Archimedean rational
function $f$ and a finite set of vertices $\Gamma$ in the Berkovich projective
line, under a certain stability hypothesis. We prove that stability can always
be attained by enlarging the vertex set $\Gamma$. As a byproduct, we deduce
that meromorphic maps preserving the fibers of a rationally-fibered complex
surface are algebraically stable after a proper modification. The first article
in this series examined the limit of the equilibrium measures for a
degenerating 1-parameter family of rational functions on the Riemann sphere.
Here we construct a convergent countable-state Markov chain that computes the
limit measure.
  A classification of the periodic Fatou components for non-Archimedean
rational functions, due to Rivera-Letelier, plays a key role in the proofs of
our main theorems. The appendix contains a proof of this classification for all
tame rational functions.


title: Bounds on depth of tensor products of modules

abstract:
  Let $R$ be a local complete intersection ring and let $M$ and $N$ be nonzero
finitely generated $R$-modules. We employ Auslander's transpose in the study of
the vanishing of Tor and obtain useful bounds for the depth of the tensor
product $M\otimes_{R}N$. An application of our main argument shows that, if $M$
is locally free on the the punctured spectrum of $R$, then either
$\depth(M\otimes_{R}N)\geq \depth(M)+\depth(N)-\depth(R)$, or
$\depth(M\otimes_{R}N)\leq \cod(R)$. Along the way we generalize an important
theorem of D. A. Jorgensen and determine the number of consecutive vanishing of
$\Tor_i^R(M,N)$ required to ensure the vanishing of all higher $\Tor_i^R(M,N)$.


title:
Structural stability of lattice-matched heterovalent semiconductor
  superlattices

abstract:
  Lattice-matched heterovalent alloys and superlattices have some unique
physical properties. For example, their band gap can change by a large amount
without significant change in their lattice constants, thus they have great
potential for optelectronic applications. Using first-principles total energy
calculation and Monte Carlo simulation as well as lattice harmonic expansion,
we systematically study the stability of the heterovalent superlattices. We
show that the chemical trend of stability of lattice-matched heterovalent
superlattices is significantly different from lattice-mismatched isovalent
superlattices, because for lattice-mismatched isovalent superlattices the
stability is mostly determined by strain, whereas for lattice-matched
nonisovalent superlattices the interfacial energy depend not only on the bond
energy but also on the Coulomb energy derived from donor- and acceptor-like
wrong bonds. In the short-period heterovalent superlattices, the abrupt [111]
interface has the lowest energy even though it is polar, whereas for the
long-period heterovalent superlattices, the [110] interface has the lowest
energy. On the contrary, [201] superlattices are usually the most stable for
lattice-mismatched isovalent superlattices.


title: Split-ball resonator

abstract:
  We introduce a new concept of split-ball resonator and demonstrate a strong
magnetic dipole response for both gold and silver spherical plasmonic
nanoparticles with nanometer-scale cuts. Tunability of the magnetic dipole
resonance throughout the visible spectral range is demonstrated by changing the
depth and width of the nanoscale cut. We realize this novel concept
experimentally by employing the laser-induced transfer method to produce
near-perfect spheres and helium ion beam milling to make cuts with the
nanometer resolution. Due to high quality of the spherical particle shape
governed by strong surface tension forces during the laser transfer process and
clean, straight side walls of the cut made by helium ion milling, the magnetic
resonance is observed at 600 nm in gold and at 565 nm in silver nanoparticles.
Structuring arbitrary features on the surface of nanoscale spherical resonators
provides new ways for engineering hybrid resonant modes and ultra-high
near-field enhancement.


title: Self-Organized Cooperative Criticality in Coupled Complex Systems

abstract:
  We show that the coupled complex systems can evolve into a new kind of
self-organized critical state where each subsystem is not critical, however,
they cooperate to be critical. This criticality is different from the classical
BTW criticality where the single system itself evolves into a critical state.
We also find that the outflows can be accumulated in the coupled systems. This
will lead to the emergency of spatiotemporal intermittency in the critical
state.


title:
First order least squares method with weakly imposed boundary condition
  for convection dominated diffusion problems

abstract:
  We present and analyze a first order least squares method for convection
dominated diffusion problems, which provides robust L2 a priori error estimate
for the scalar variable even if the given data f in L2 space. The novel
theoretical approach is to rewrite the method in the framework of discontinuous
Petrov - Galerkin (DPG) method, and then show numerical stability by using a
key equation discovered by J. Gopalakrishnan and W. Qiu [Math. Comp. 83(2014),
pp. 537-552]. This new approach gives an alternative way to do numerical
analysis for least squares methods for a large class of differential equations.
We also show that the condition number of the global matrix is independent of
the diffusion coefficient. A key feature of the method is that there is no
stabilization parameter chosen empirically. In addition, Dirichlet boundary
condition is weakly imposed. Numerical experiments verify our theoretical
results and, in particular, show our way of weakly imposing Dirichlet boundary
condition is essential to the design of least squares methods - numerical
solutions on subdomains away from interior layers or boundary layers have
remarkable accuracy even on coarse meshes, which are unstructured
quasi-uniform.


title:
Total Jensen divergences: Definition, Properties and k-Means++
  Clustering

abstract:
  We present a novel class of divergences induced by a smooth convex function
called total Jensen divergences. Those total Jensen divergences are invariant
by construction to rotations, a feature yielding regularization of ordinary
Jensen divergences by a conformal factor. We analyze the relationships between
this novel class of total Jensen divergences and the recently introduced total
Bregman divergences. We then proceed by defining the total Jensen centroids as
average distortion minimizers, and study their robustness performance to
outliers. Finally, we prove that the k-means++ initialization that bypasses
explicit centroid computations is good enough in practice to guarantee
probabilistically a constant approximation factor to the optimal k-means
clustering.


title:
LHC and Tevatron constraints on a W' model interpretation of the top
  quark forward-backward asymmetry

abstract:
  Aspects of a flavor-changing W' model with right-handed couplings are
addressed in this paper in light of Tevatron and LHC data. Our fit to the
Tevatron top-quark forward-backward asymmetry and the tt_bar inclusive cross
section includes higher-order loop effects in the effective interaction. The
higher order corrections change the best fit value of the W' effective coupling
strength as a function of the W' mass. The consistency of the model is checked
against the shape of the tt_bar invariant mass distribution. We use these
updated W' parameters to compute the expected contributions from W't associated
production and, for the first time, W'W' pair production at the LHC. We do a
full Monte Carlo simulation of the tt_bar+X final state, including interference
between the tW' induced tt_bar j process and the standard model tt_bar j
process. Interference effects are shown to be quantitatively important,
particularly when the W' mass is large. The jet multiplicity distribution in
tt_bar-jet production at 8 TeV constrains the W' model severely.


title: Some Wilf-equivalences for vincular patterns

abstract:
  We prove several Wilf-equivalences for vincular patterns of length 4, some of
which generalize to infinite families of vincular patterns. We also present
functional equations for the generating functions for the number of
permutations of length n avoiding a single pattern for the patterns 124-3,
134-2, 231-4, 241-3, 132-4, and 142-3. This nearly completes the
Wilf-classification of vincular patterns of length 4. As a corollary, these
results imply Wilf-equivalences for certain barred patterns of length 5 with a
single bar.


title: A Jarn\'ik type theorem for planar curves: everything about the parabola

abstract:
  The well known theorems of Khintchine and Jarn\'ik in metric Diophantine
approximation provide comprehensive description of the measure theoretic
properties of real numbers approximable by rational numbers with a given error.
Various generalisations of these fundamental results have been obtained for
other settings, in particular, for curves and more generally manifolds. In this
paper we develop the theory for planar curves by completing the theory in the
case of parabola. This represents the first comprehensive study of its kind in
the theory of Diophantine approximation on manifolds.


title: Horospherical limit points of S-arithmetic groups

abstract:
  Suppose Gamma is an S-arithmetic subgroup of a connected, semisimple
algebraic group G over a global field Q (of any characteristic). It is well
known that Gamma acts by isometries on a certain CAT(0) metric space X_S that
is a Cartesian product of Euclidean buildings and Riemannian symmetric spaces.
For a point p on the visual boundary of X_S, we show there exists a horoball
based at p that is disjoint from some Gamma-orbit in X_S if and only if p lies
on the boundary of a certain type of flat in X_S that we call "Q-good." This
generalizes a theorem of G.Avramidi and D.W.Morris that characterizes the
horospherical limit points for the action of an arithmetic group on its
associated symmetric space.


title: Gamma-ray emission from massive stars interacting with AGN jets

abstract:
  Dense populations of stars surround the nuclear regions of galaxies. In
active galactic nuclei, these stars can interact with the relativistic jets
launched by the supermasive black hole. In this work, we study the interaction
of early-type stars with relativistic jets in active galactic nuclei. A
bow-shaped double-shock structure is formed as a consequence of the interaction
of the jet and the stellar wind of each early-type star. Particles can be
accelerated up to relativistic energies in these shocks and emit high-energy
radiation. We compute, considering different stellar densities of the galactic
core, the gamma-ray emission produced by non-thermal radiative processes. This
radiation may be significant in some cases, and its detection might yield
valuable information on the properties of the stellar population in the galaxy
nucleus, as well as on the relativistic jet. This emission is expected to be
particularly relevant for nearby non-blazar sources.


title: Probabilistically nilpotent Hopf algebras

abstract:
  In this paper we investigate nilpotenct and probabilistically nilpotent Hopf
algebras. We define nilpotency via a descending chain of commutators and give a
criterion for nilpotency via a family of central invertible elements. These
elements can be obtained from a {\it commutator matrix} $A$ which depends only
on the Grothendieck ring of $H.$ When $H$ is almost cocommutative we introduce
a probabilistic method. We prove that every semisimple quasitriangular Hopf
algebra is probabilistically nilpotent. In a sense we thereby answer the title
of our paper {\it Are we counting or measuring anything?} by {\it Yes we are}.


title: Current Dependence of Spin Torque Switching Barrier

abstract:
  The current dependence of the switching barrier for spin torque switching of
an in-plane magnetized ferromagnet was studied. Two scaling currents, I_{c}$
and I_{c}^{*}(>I_{c}), were introduced to distinguish the magnetization
stability. In the low-current region I<I_{c}, the switching barrier is linear
to the current with another scaling current \tilde{I}_{c}, while such linear
scaling does not hold in the high-current region I_{c} < I < I_{c}^{*}. The
linear scaling is valid for the high temperature and the long current pulse
duration time.


title: Using functional equations to enumerate 1324-avoiding permutations

abstract:
  We consider the problem of enumerating permutations with exactly r
occurrences of the pattern 1324 and derive functional equations for this
general case as well as for the pattern avoidance (r=0) case. The functional
equations lead to a new algorithm for enumerating length n permutations that
avoid 1324. This approach is used to enumerate the 1324-avoiders up to n=31. We
also extend those functional equations to account for the number of inversions
and derive analogous algorithms.


title:
Asymptotics for a nonlinear integral equation with a generalized heat
  kernel

abstract:
  This paper is concerned with a nonlinear integral equation $$ (P)\qquad
u(x,t)=\int_{{\bf R}^N}G(x-y,t)\varphi(y)dy+\int_0^t\int_{{\bf
R}^N}G(x-y,t-s)f(y,s:u)dyds, \quad $$ where $N\ge 1$, $\varphi\in L^\infty({\bf
R}^N)\cap L^1({\bf R}^N,(1+|x|^K)dx)$ for some $K\ge 0$. Here $G=G(x,t)$ is a
generalization of the heat kernel. We are interested in the asymptotic
expansions of the solution of $(P)$ behaving like a multiple of the integral
kernel $G$ as $t\to\infty$.


title:
Stock price direction prediction by directly using prices data: an
  empirical study on the KOSPI and HSI

abstract:
  The prediction of a stock market direction may serve as an early
recommendation system for short-term investors and as an early financial
distress warning system for long-term shareholders. Many stock prediction
studies focus on using macroeconomic indicators, such as CPI and GDP, to train
the prediction model. However, daily data of the macroeconomic indicators are
almost impossible to obtain. Thus, those methods are difficult to be employed
in practice. In this paper, we propose a method that directly uses prices data
to predict market index direction and stock price direction. An extensive
empirical study of the proposed method is presented on the Korean Composite
Stock Price Index (KOSPI) and Hang Seng Index (HSI), as well as the individual
constituents included in the indices. The experimental results show notably
high hit ratios in predicting the movements of the individual constituents in
the KOSPI and HIS.


title: Wheel-free planar graphs

abstract:
  A \emph{wheel} is a graph formed by a chordless cycle $C$ and a vertex $u$
not in $C$ that has at least three neighbors in $C$. We prove that every
3-connected planar graph that does not contain a wheel as an induced subgraph
is either a line graph or has a clique cutset. We prove that every planar graph
that does not contain a wheel as an induced subgraph is 3-colorable.


title: Finiteness of stable orthogonal modular varieties of non-general type

abstract:
  We prove that there are only finitely many even lattices L of signature (2,n)
with n>14 such that the modular variety defined by the stable orthogonal group
of L is not of general type.


title:
Proceedings Wivace 2013 - Italian Workshop on Artificial Life and
  Evolutionary Computation

abstract:
  The Wivace 2013 Electronic Proceedings in Theoretical Computer Science
(EPTCS) contain some selected long and short articles accepted for the
presentation at Wivace 2013 - Italian Workshop on Artificial Life and
Evolutionary Computation, which was held at the University of Milan-Bicocca,
Milan, on the 1st and 2nd of July, 2013.


title:
$L^p$ $(p\geq 1)$ solutions of multidimensional BSDEs with monotone
  generators in general time intervals

abstract:
  In this paper, we are interested in solving general time interval
multidimensional backward stochastic differential equations in $L^p$ $(p\geq
1)$. We first study the existence and uniqueness for $L^p$ $(p>1)$ solutions by
the method of convolution and weak convergence when the generator is monotonic
in $y$ and Lipschitz continuous in $z$ both non-uniformly with respect to $t$.
Then we obtain the existence and uniqueness for $L^1$ solutions with an
additional assumption that the generator has a sublinear growth in $z$
non-uniformly with respect to $t$.


title:
Pair-Tunneling Induced Localized Waves in a Vector Nonlinear
  Schr\"{o}dinger Equation

abstract:
  We investigate the localized waves of the coupled two-mode nonlinear
Schr\"{o}dinger equations with a pair-tunneling term representing strongly
interacting particles can tunnel between the modes as a fragmented pair.
Facilitated by Darboux transformation, we have derived exact solution of
nonlinear vector waves such as bright solitons, Kuznetsov-Ma soliton, Akhmediev
breathers and rogue waves and demonstrated their interesting temporal-spatial
structures. The phase diagram that demarcates the parameter ranges of the
nonlinear waves is obtained.
  Our results have implications in such diverse fields as Bose-Einstein
condensate, nonlinear fibers and super fluids.


title: Tensorial conservation law for nematic polymers

abstract:
  We derive the "conservation law" for nematic polymers in tensorial form valid
for quadrupolar orientational order in contradistinction to the conservation
law in the case of polar orientational order. Due to microscopic differences in
the coupling between the orientational field deformations and the density
variations for polar and quadrupolar order, we find that respective order
parameters satisfy fundamentally distinct constraints. Being necessarily scalar
in its form, the tensorial conservation law is obtained straightforwardly from
the gradients of the polymer nematic tensor field and connects the spatial
variation of this tensor field with density variations. We analyze the
differences between the polar and the tensorial forms of the conservation law,
present some explicit orientational fields that satisfy this new constraint and
discuss the role of singular "hairpins", which do not affect local quadrupolar
order of polymer nematics, but nevertheless influence its gradients.


title:
Generation and evolution of stable stellar magnetic fields in young
  A-type stars

abstract:
  While the presence of magnetic fields on low-mass stars is attributed to a
dynamo process essentially driven by convective motions, the existence of
magnetic fields on intermediate-mass stars has very likely other reasons.
Presuming that the fields we see are nearly constant in time, the paper focuses
on the generation of stable magnetic configurations at the early stages of
stellar evolution. The convective processing of an initial magnetic field
during the pre-main-sequence phase is studied in a very simple model star.
Azimuthal magnetic fields are found to be typical remnants in the upcoming
radiative envelope after the convection has receded.


title:
W40 region in the Gould Belt : An embedded cluster and H II region at
  the junction of filaments

abstract:
  We present a multiwavelength study of W40 star-forming region using IR
observations in UKIRT JHK bands, Spitzer IRAC bands & Herschel PACS bands; 2.12
micron H2 narrow-band imaging; & radio observations from GMRT (610 & 1280 MHz),
in a FoV of ~34'x40'. Spitzer observations along with NIR observations are used
to identify 1162 Class II/III & 40 Class I sources in the FoV. The NN stellar
surface density analysis shows that majority of these YSOs constitute the
embedded cluster centered on the source IRS1A South. Some YSOs, predominantly
younger population, are distributed along & trace the filamentary structures at
lower stellar surface density. The cluster radius is obtained as 0.44pc -
matching well with the extent of radio emission - with a peak density of
650pc^-2. The JHK data is used to map the extinction which is subsequently used
to compute the cloud mass. It has resulted in 126 Msun & 71 Msun for the
central cluster & the northern IRS5 region, respectively. H2 narrow-band
imaging displays significant emission, which prominently resembles fluorescent
emission arising at the borders of dense regions. Radio analysis shows this
region as having blister morphology, with the radio peak coinciding with a
protostellar source. Free-free emission SED analysis is used to obtain physical
parameters of the overall region & the IRS5 sub-region. This multiwavelength
scenario is suggestive of star formation having resulted from merging of
multiple filaments to form a hub. Star formation seems to have taken place in
two successive epochs, with the first epoch traced by the central cluster & the
high-mass star(s) - followed by a second epoch which is spreading into the
filaments as uncovered by the Class I sources & even younger protostellar
sources along the filaments. The IRS5 HII region displays indications of
swept-up material which has possibly led to the formation of protostars.


title:
A GPU cluster optimized multigrid scheme for computing unsteady
  incompressible fluid flow

abstract:
  A multigrid scheme is proposed for the pressure equation of the
incompressible unsteady fluid flow equations, allowing efficient implementation
on clusters of modern CPUs, many integrated core devices (MICs), and graphics
processing units (GPUs). It is shown that the total number of the
synchronization events can be significantly reduced when a deep, 2h grid
hierarchy is replaced with a two-level scheme using 16h-32h restriction,
fitting to the the width of the SIMD engine of modern CPUs and GPUs. In
addition, optimal memory transfer is also ensured, since no strided memory
access is required. We report increasing arithmetic intensity of the smoothing
steps when compared to the conventional additive correction multigrid (ACM),
however it is counterbalanced in runtime by the decreasing number of the
expensive restriction steps. A systematic construction methodology for the
coarse grid stencil is also presented that helps in moderating the excess
arithmetic intensity associated with the aggressive coarsening. Our higher
order interpolated stencil improves convergence rate via minimizing spurious
interference between the coarse and the fine scale solutions. The method is
demonstrated on solving the pressure equation for 2D incompressible fluid flow:
The benchmark setups cover shear driven laminar flow in cavity, and direct
numerical simulation (DNS) of a turbulent jet. We have compared our scheme to
the ACM in terms of the arithmetic intensity of the iterations and the number
of the synchronization calls required. Also the strong scaling is plotted for
our scheme when using a hybrid OpenCl/MPI based parallelization.


title:
A new approach to the assessment of stochastic errors of radio source
  position catalogues

abstract:
  Assessing the external stochastic errors of radio source position catalogues
derived from VLBI observations is important for tasks such as estimating the
quality of the catalogues and their weighting during combination. One of the
widely used methods to estimate these errors is the three-cornered-hat
technique, which can be extended to the N-cornered-hat technique. A critical
point of this method is how to properly account for the correlations between
the compared catalogues. We present a new approach to solving this problem that
is suitable for simultaneous investigations of several catalogues. To compute
the correlation between two catalogues $A$ and $B$, the differences between
these catalogues and a third arbitrary catalogue $C$ are computed. Then the
correlation between these differences is considered as an estimate of the
correlation between catalogues $A$ and $B$. The average value of these
estimates over all catalogues $C$ is taken as a final estimate of the target
correlation. In this way, an exhaustive search of all possible combinations
allows one to compute the paired correlations between all catalogues. As an
additional refinement of the method, we introduce the concept of weighted
correlation coefficient. This technique was applied to nine recently published
radio source position catalogues. We found large systematic differences between
catalogues, that significantly impact determination of their stochastic errors.
Finally, we estimated the stochastic errors of the nine catalogues.


title:
The Beurling--Malliavin Multiplier Theorem and its analogs for the de
  Branges spaces

abstract:
  Let $\omega$ be a non-negative function on $\mathbb{R}$. We are looking for a
non-zero $f$ from a given space of entire functions $X$ satisfying $$(a)
\quad|f|\leq \omega\text{\quad or\quad(b)}\quad |f|\asymp\omega.$$ The
classical Beurling--Malliavin Multiplier Theorem corresponds to $(a)$ and the
classical Paley--Wiener space as $X$. We survey recent results for the case
when $X$ is a de Branges space $\he$. Numerous answers mainly depend on the
behaviour of the phase function of the generating function $E$.


title: Possible extended forms of thermodynamic entropy

abstract:
  Thermodynamic entropy is determined by a heat measurement through the
Clausius equality. The entropy then formalizes a fundamental limitation of
operations by the second law of thermodynamics. The entropy is also expressed
as the Shannon entropy of the microscopic degrees of freedom. Whenever an
extension of thermodynamic entropy is attempted, we must pay special attention
to how its three different aspects just mentioned are altered. In this paper,
we discuss possible extensions of the thermodynamic entropy.


title: Microscopic description of the odd-even effect in cold fission

abstract:
  The time dependent equations of motion for the pair breaking effect were
corroborated with a condition that fixes dynamically the number of particles on
the two fission fragment. The single particle level scheme was calculated with
the Woods-Saxon superasymmetric two center shell model. This model provides a
continuous variation of the energies from one nucleus up to two separated
fragments. The dissipated energy resorts from the time dependent pairing
equations. A peculiar phenomenon was observed experimentally in cold fission:
the odd partition yields are favored over the even ones. This odd-even effect
for cold fission was explained microscopically.


title:
On classification of quantum groups and Belavin-Drinfeld twisted
  cohomologies

abstract:
  The present article is a continuation of QA/1303.4046, where we discussed the
classification of quantum groups with quasi-classical limit $\mathfrak{g}$ and
introduced a theory of Belavin-Drinfeld cohomology associated to any
non-skewsymmetric $r$-matrix. Depending on the form of the corresponding
double, there exists a one-to-one correspondence between gauge equivalence
classes of Lie bialgebra structures on
$\mathfrak{g}\otimes_{\mathbb{C}}\mathbb{K}$, where
$\mathbb{K}=\mathbb{C}((\hbar))$, and untwisted or twisted cohomology classes.
In the present paper we investigate twisted cohomologies for $sl(n)$ associated
to generalized Cremmer-Gervais $r$-matrices, and twisted cohomologies for
$o(n)$.


title: Multimode strong-coupling quantum optomechanics

abstract:
  We study theoretically the dynamics of multiple mechanical oscillators
coupled to a single cavity field mode via linear or quadratic optomechanical
interactions. We focus specifically on the strong coupling regime where the
cavity decays much faster than the mechanical modes, and the optomechanical
coupling is comparable to or larger than the mechanical frequency, so that both
the optical and mechanical systems operate in the deep quantum regime. Using
the examples of one and two mechanical oscillators we show that the system can
classically exhibit bistability and bifurcations, and we explore how these
manifest themselves in interference, entanglement, and correlation in the
quantum theory, while revealing the impact of decoherence of the mechanical
system due to cavity fluctuations and coherent driving.


title: Re-analysis of the $\Lambda(1520)$ photoproduction reaction

abstract:
  Based on previous studies that support the important role of the $N^*(2120)
D_{13}$ resonance in the $\gamma p \to K^+ \Lambda(1520)$ reaction, we make a
re-analysis of this $\Lambda(1520)$ photoproduction reaction taking into
account the recent CLAS differential cross-section data. In addition to the
contact, $t-$channel $\bar K$ exchange, $s-$channel nucleon pole and
$N^*(2120)$ [previously called $N^*(2080)$] resonance contributions, which have
been already considered in previous works, we also study the $u-$channel
$\Lambda(1115)$ hyperon pole term. The latter mechanism has always been ignored
in all theoretical analysis, which has mostly relied on the very forward $K^+$
angular LEPS data. It is shown that when the contributions from the $N^*(2120)$
resonance and the $\Lambda(1115)$ hyperon are taken into account, both the new
CLAS and the previous LEPS data can be simultaneously described. We also show
that the contribution from the $u-$channel $\Lambda(1115)$ pole term produces
an enhancement for large $K^+$ angles, and it becomes more and more relevant as
the photon energy increases, being essential to describe the CLAS differential
cross sections at backward angles. Furthermore, we find that the new CLAS data
also favor the existence of the $N^*(2120)$ resonance, and that these
measurements can be used to further constrain its properties.


title:
Beating the superparamagnetic size limit of nanoparticles on a
  ferroelectric substrate

abstract:
  When decreasing the size of nanoscale magnetic particles their magnetization
becomes vulnerable to thermal fluctuations as approaching the superparamgnetic
limit, hindering thus applications relying on a stable magnetization. Here, we
show theoretically that a magnetoelectric coupling to a ferroelectric substrate
renders possible the realization of substantially smaller nano clusters with
thermally stable magnetization. For an estimate of cluster size we perform
calculations with realistic material parameters for iron nano particles on
ferroelectric BaTiO3 substrate. We find, steering the polarization of BaTiO3
with electric fields affects the magnetism of the deposited magnetic clusters.
These findings point to a qualitatively new class of superparamagnetic
composites.


title: Time-dependent Modeling of Pulsar Wind Nebulae

abstract:
  A spatially independent model that calculates the time evolution of the
electron spectrum in a spherically expanding pulsar wind nebula (PWN) is
presented, allowing one to make broadband predictions for the PWN's non-thermal
radiation. The source spectrum of electrons injected at the termination shock
of the PWN is chosen to be a broken power law. In contrast to previous PWN
models of a similar nature, the source spectrum has a discontinuity in
intensity at the transition between the low and high-energy components. To test
the model, it is applied to the young PWN G21.5--0.9, where it is found that a
discontinuous source spectrum can model the emission at all wavelengths better
than a continuous one. The model is also applied to the unidentified sources
HESS J1427--608 and HESS J1507--622. Parameters are derived for these two
candidate nebulae that are consistent with the values predicted for other PWNe.
For HESS J1427--608 a present-day magnetic field of $B\s{age}=0.4\,\mu\text{G}$
is derived. As a result of the small present-day magnetic field, this source
has a low synchrotron luminosity, while remaining bright at GeV/TeV energies.
It is therefore possible to interpret HESS J1427--608 within the ancient PWN
scenario. For the second candidate PWN HESS J1507--622, a present-day magnetic
field of $B\s{age}=1.7\,\mu\text{G}$ is derived. Furthermore, for this
candidate PWN a scenario is favoured in the present paper in which HESS
J1507--622 has been compressed by the reverse shock of the supernova remnant.


title: On a question of Abraham Robinson's

abstract:
  In this note we give a negative answer to Abraham Robinson's question whether
a finitely generated extension of an undecidable field is always undecidable.
We construct 'natural' undecidable fields of transcendence degree 1 over Q all
of whose proper finite extensions are decidable. We also construct undecidable
algebraic extensions of Q that allow decidable finite extensions.


title:
Self-Sustained Turbulence without Dynamical Forcing: A Two-Dimensional
  Study of a Bistable Interstellar Medium

abstract:
  In this paper, the nonlinear evolution of a bistable interstellar medium is
investigated using two-dimensional simulations with a realistic cooling rate,
thermal conduction, and physical viscosity. The calculations are performed
using periodic boundary conditions without any external dynamical forcing. As
the initial condition, a spatially uniform unstable gas under thermal
equilibrium is considered. At the initial stage, the unstable gas quickly
segregates into two phases, or cold neutral medium (CNM) and warm neutral
medium (WNM). Then, self-sustained turbulence with velocity dispersion of
$0.1-0.2\;\mathrm{km\;s^{-1}}$ is observed in which the CNM moves around in the
WNM. We find that the interfacial medium (IFM) between the CNM and WNM plays an
important role in sustaining the turbulence. The self-sustaining mechanism can
be divided into two steps. First, thermal conduction drives fast flows
streaming into concave CNM surfaces towards the WNM. The kinetic energy of the
fast flows in the IFM is incorporated into that of the CNM through the phase
transition. Second, turbulence inside the CNM deforms interfaces and forms
other concave CNM surfaces, leading to fast flows in the IFM. This drives the
first step again and a cycle is established by which turbulent motions are
self-sustained.


title: Establishing digital molecular communications in blood vessels

abstract:
  In this paper we propose a solution for transmitting digital information
within the cardiocirculatory system. In particular, we make use of a channel
delivering burst of molecules, emitted by mobile transmitters, which diffuse in
the blood towards fixed receivers, that are attached to the vessel walls. This
communication scheme has been inspired by the real signaling between platelets
and endothelial cells, the behavior of which has been investigated
experimentally. We thus believe that our proposal can be successfully deployed
in living bodies. On the basis of the results achieved through simulations on
the communication system capabilities, we propose a simple but effective
receiver scheme, and we outline the future research directions.


title: A general method for common intervals

abstract:
  Given an elementary chain of vertex set V, seen as a labelling of V by the
set {1, ...,n=|V|}, and another discrete structure over $V$, say a graph G, the
problem of common intervals is to compute the induced subgraphs G[I], such that
$I$ is an interval of [1, n] and G[I] satisfies some property Pi (as for
example Pi= "being connected"). This kind of problems comes from comparative
genomic in bioinformatics, mainly when the graph $G$ is a chain or a tree
(Heber and Stoye 2001, Heber and Savage 2005, Bergeron et al 2008).
  When the family of intervals is closed under intersection, we present here
the combination of two approaches, namely the idea of potential beginning
developed in Uno, Yagiura 2000 and Bui-Xuan et al 2005 and the notion of
generator as defined in Bergeron et al 2008. This yields a very simple generic
algorithm to compute all common intervals, which gives optimal algorithms in
various applications. For example in the case where $G$ is a tree, our
framework yields the first linear time algorithms for the two properties:
"being connected" and "being a path". In the case where $G$ is a chain, the
problem is known as: common intervals of two permutations (Uno and Yagiura
2000), our algorithm provides not only the set of all common intervals but also
with some easy modifications a tree structure that represents this set.


title:
Multiplicity of normalized solutions for a class of nonlinear
  Schrodinger-Poisson-Slater equations

abstract:
  In this paper, we prove a multiplicity result of solutions for the following
stationary Schr\"odinger-Poisson-Slater equations
\begin{equation}\label{eq-abstract} -\Delta u - \lambda u + (\left | x \right
|^{-1}\ast \left | u \right |^2) u - |u|^{p-2}u = 0 \ \mbox{ in } \
\mathbb{R}^{3}, \end{equation} where $\lambda\in \R$ is a parameter, and $p\in
(2,6)$. The solutions we obtained have a prescribed $L^2$-norm. Our proofs are
mainly inspired by a recent work of Bartsch and De Valeriola [7].


title:
The orbits of subdwarf-B + main-sequence binaries. II. Three eccentric
  systems; BD+29 3070, BD +34 1543 and Feige 87

abstract:
  The predicted orbital-period distribution of the subdwarf-B (sdB) population
is bi-modal with a peak at short (< 10 days) and long (> 250 days) periods.
Observationally, many short-period sdB systems are known, but the predicted
long period peak is missing as orbits have only been determined for a few
long-period systems. As these predictions are based on poorly understood
binary-interaction processes, it is of prime importance to confront the
predictions with reliable observational data. We therefore initiated a
monitoring program to find and characterize long-period sdB stars. In this
paper we aim to determine the orbital parameters of the three long-period
sdB+MS binaries BD+29 3070, BD+34 1543 and Feige 87, to constrain their
absolute dimensions and the physical parameters of the components.
High-resolution spectroscopic time series were obtained with HERMES at the
Mercator telescope on La Palma, and analyzed to determine the radial velocities
of both the sdB and MS components. Photometry from the literature was used to
construct the spectral-energy distribution (SED) of the binaries. Atmosphere
models were used to fit these SEDs and to determine the surface gravities and
temperatures of both components of all systems. Spectral analysis was used to
check the results of the SEDs. An orbital period of 1283 +- 63 d, a mass ratio
of q = 0.39 +- 0.04 and a significant non-zero eccentricity of e = 0.15 +- 0.01
were found for BD+29 3070. For BD+34 1543 we determined P = 972 +- 2 d, q =
0.57 +- 0.01 and again a clear non-zero eccentricity of e = 0.16 +- 0.01. Last,
for Feige 87 we found P = 936 +- 2 d, q = 0.55 +- 0.01 and e = 0.11 +- 0.01.
BD+29 3070, BD+34 1543 and Feige 87 are long period sdB + MS binaries on
clearly eccentric orbits. These results are in conflict with the predictions of
stable Roche-lobe overflow models.


title:
Fully cosmological virtual massive galaxies at z=0: kinematical,
  morphological, and stellar population characterisation

abstract:
  We present the results of a numerical adaptive mesh refinement hydrodynamical
and N-body simulation in a $\Lambda CDM$ cosmology. We focus on the analysis of
the main properties of massive galaxies ($M_* > 10^{11}\,M_{\odot}$) at $z=0$.
For all the massive virtual galaxies we carry out a careful study of their one
dimensional density, luminosity, velocity dispersion, and stellar population
profiles. In order to best compare with observational data, the method to
estimate the velocity dispersion is calibrated by using an approach similar to
that performed in the observations, based on the stellar populations of the
simulated galaxies. With these ingredients, we discuss the different properties
of massive galaxies in our sample according to their morphological types,
accretion histories and dynamical properties. We find that the galaxy merging
history is the leading actor in shaping the massive galaxies that we see
nowadays. Indeed, galaxies having experienced a turbulent life are the most
massive in the sample and show the steepest metallicity gradients. Beside the
importance of merging, only a small fraction of the final stellar mass has been
formed ex-situ (10-50%), while the majority of the stars formed within the
galaxy. These accreted stars are significantly older and less metallic than the
stars formed in-situ and tend to occupy the most external regions of the
galaxies.


title: Propagating Regular Counting Constraints

abstract:
  Constraints over finite sequences of variables are ubiquitous in sequencing
and timetabling. Moreover, the wide variety of such constraints in practical
applications led to general modelling techniques and generic propagation
algorithms, often based on deterministic finite automata (DFA) and their
extensions. We consider counter-DFAs (cDFA), which provide concise models for
regular counting constraints, that is constraints over the number of times a
regular-language pattern occurs in a sequence. We show how to enforce domain
consistency in polynomial time for atmost and atleast regular counting
constraints based on the frequent case of a cDFA with only accepting states and
a single counter that can be incremented by transitions. We also prove that the
satisfaction of exact regular counting constraints is NP-hard and indicate that
an incomplete algorithm for exact regular counting constraints is faster and
provides more pruning than the existing propagator from [3]. Regular counting
constraints are closely related to the CostRegular constraint but contribute
both a natural abstraction and some computational advantages.


title:
Why asymmetric interparticle interaction can result in convergent heat
  conductivity

abstract:
  We show that the asymmetric inter-particle interactions may induce rapid
decay of heat current autocorrelation in one-dimensional momentum conserving
lattices. When the asymmetry degree and the temperature are appropriate, the
decay is sufficient rapid for resulting a convergence conductivity practically.
To understand the underlying mechanism, we further studied the relaxation
behavior of the hydrodynamic modes. It is shown that for lattice with symmetric
potential, the heat mode relaxs in the superdiffusive manner, while in the case
of asymmetric potential, the heat mode may relax in the normal manner.


title:
Stress relaxation for granular materials near Jamming under cyclic
  compression

abstract:
  We have explored isotropically jammed states of semi-2D granular materials
through cyclic compression. In each compression cycle, systems of either
identical ellipses or bi-disperse disks, transition between jammed and unjammed
states. We determine the evolution of the average pressure, P, and structure
through consecutive jammed states. We observe a transition point, {\phi}m,
above which P persists over many cycles; below {\phi}m, P relaxes slowly. The
relaxation time scale associated with P increases with packing fraction, while
the relaxation time scale for collective particle motion remains constant. The
collective motion of the ellipses is hindered compared to disks, due to the
rotational constraints on elliptical particles.


title:
Preparation and tunable mid-IR optical properties of ternary
  Cd_{1-x}Pb_xS nanocrystals by mechanical alloying

abstract:
  Composition-tunable ternary Cd1-xPbxS nanocrystals (NCs) are very important
materials for remote sensing and detecting in the infrared (IR) wavelength
region. They are, however, almost exclusively prepared by wet chemical routes
which leads to surface-capped nanoparticles. The surface capping molecules
could move their absorption peak from mid-IR to near IR wavelength region.
However, surface clean Cd1-xPbxS nanocrystals (NCs) would demonstrate intrinsic
optical spectrum in the mid-IR region. Herein, we present a physical mechanical
alloying process being applied to prepare tens of grams of surface clean
Cd1-xPbxS nanocrystals within the composition range of x=0.5 to 1. The
resulting nanocrystals have average sizes smaller than 9 nm, are chemically
homogenous, show a continuous lattice expansion with Pb content and a nonlinear
band gap-composition relationship, demonstrating the ability to continuously
and precisely tune the band gap energies of ternary Cd1-xPbxS semiconductor
nanocrystals from mid-IR region (2638 nm) to NIR wavelength region (1059 nm)
through chemical composition.


title:
Orbital motions and the conservation-law/preferred-frame $\alpha_3$
  parameter

abstract:
  We analytically calculate some orbital effects induced by the
Lorentz-invariance/momentum-conservation PPN parameter $\alpha_3$ in a
gravitationally bound binary system made of a compact primary orbited by a test
particle. We neither restrict ourselves to any particular orbital configuration
nor to specific orientations of the primary's spin axis
$\boldsymbol{\hat{\psi}}$. We use our results to put preliminary upper bounds
on $\alpha_3$ in the weak-field regime by using the latest data from Solar
System's planetary dynamics. By linearly combining the supplementary perihelion
precessions $\Delta\dot\varpi$ of the Earth, Mars and Saturn, determined with
the EPM2011 ephemerides, we infer $|\alpha_3|\lesssim 6\times 10^{-10}$. Our
result is about 3 orders of magnitude better than the previous weak-field
constraints existing in the literature, and of the same order of magnitude of
the bound expected from the future BepiColombo mission to Mercury. It is, by
construction, independent of the other preferred-frame PPN parameters
$\alpha_1,\alpha_2$, both preliminarily constrained down to a $\approx 10^{-6}$
level. The wide pulsar-white dwarf binary PSR J0407+1607 yields a preliminary
upper bound on the strong-field version $\hat{\alpha}_3$ of the
Lorentz-invariance/momentum-conservation PPN parameter of the order of $3\times
10^{-17}$. It relies upon certain assumptions on the unknown values of the
pulsar's spin axis orientation $\boldsymbol{\hat{\psi}}$, the orbital node
$\Omega$ and the inclination $I$. Neither the pulsar's proper motion, still
undetected, nor a possible value of the pulsar's mass $m_{\rm p}$ up to two
solar masses substantially affect our result.


title:
Quasistatic adhesive contact delaminating in mixed mode and its
  numerical treatment

abstract:
  An adhesive unilateral contact between visco-elastic bodies at small strains
and in a Kelvin-Voigt rheology is scrutinized, neglecting inertia. The
flow-rule for debonding the adhesive is considered rate independent,
unidirectional, and non-associative due to dependence on the mixity of modes of
delamination, namely Mode I (opening) needs (=dissipates) less energy than Mode
II (shearing). Such mode-mixity dependence of delamination is a very pronounced
(and experimentally confirmed) phenomenon typically considered in engineering
models.
  An efficient semi-implicit-in-time FEM discretization leading to recursive
quadratic mathematical programs is devised. Its convergence and thus the
existence of weak solutions is proved. Computational experiments implemented by
BEM illustrate the modeling aspects and the numerical efficiency of the
discretization.


title:
Dynamics of Sheared Ellipses and Circular Disks: Effects of Particle
  Shape

abstract:
  Much recent effort has focused on glassy and jamming properties of spherical
particles. Very little is known about such phenomena for non-spherical
particles, and we take a first step by studying ellipses. We find important
differences between the dynamical and structural properties of disks and
two-dimensional ellipses subject to continuous Couette shear. In particular,
ellipses show slow dynamical evolution, without a counterpart in disks, in the
mean velocity, local density, orientational order, and local stress. starting
from an unjammed state, ellipses can first jam under shear, and then slowly
unjam. The slow unjamming process is understood as a result of gradual changes
in their orientations, leading to a denser packing. For disks, the rotation of
particles only contributes to relaxation of frictional forces, and hence, does
not significantly cause structural changes. For the shear-jammed states, the
global building up and relaxation of stress, which occurs in the form of stress
avalanches, is qualitatively different for disks and ellipses, and is
manifested by different forms of rate-dependence for ellipses vs. disks. Unlike
the weak rate dependence typical for many granular systems, ellipses show
power-law dependence on the shearing rate, {\Omega}.


title: Exact Solutions of One-Dimensional TGV

abstract:
  L2-TGV-regularization has been introduced by Bredies, Kunisch, and Pock. This
regularization method requires careful tuning of two regularization parameters.
The focus of this paper is to derive analytical results, which allow for
characterizing parameter settings, which make this method in fact different
from L2-TV (the ROF-model) and L2-TV2 regularization, respectively. In this
paper we also provide explicit solutions of TGV-denoising for particular
one-dimensional function data.


title:
Brou\'e's abelian defect group conjecture and 3-decomposition numbers of
  the sporadic simple Conway group Co_1

abstract:
  In the representation theory of finite groups, Brou\'e's abelian defect group
conjecture says that for any prime p if a p-block A of a finite group G has an
abelian defect group P, then A and its Brauer corresponding block B of the
normaliser N_G(P) of P in G are derived equivalent. We prove that Brou\'e's
conjecture, and even Rickard's splendid equivalence conjecture, are true for
the unique 3-block A of defect 2 of the sporadic simple Conway group Co_1,
implying that both conjectures hold for all 3-blocks of Co_1. To do so, we
determine the 3-decomposition numbers of A, and we actually show that A is Puig
equivalent to the principal 3-block of the symmetric group S_6 of degree 6.


title: Scalar glueball in a soft-wall model of AdS/QCD

abstract:
  The scalar glueball is investigated in a soft-wall model of AdS/QCD.
Constraints of the mass of the scalar glueball are given through an analysis of
a relation between the bulk mass and the anomalous dimension. The mass of the
ground scalar glueball is located at $0.96^{+0.04}_{-0.07}
\rm{GeV}<m_G<1.36^{+0.05}_{-0.10}\rm{GeV}$. In terms of a background dilaton
field $\Phi(z)=cz^2$, the two-point correlation function for the scalar gluon
operator is obtained. The two-point correlation function at $\Delta=4$ gives a
different behavior compared with the one in QCD.


title:
Finite Type Invariants of w-Knotted Objects: From Alexander to Kashiwara
  and Vergne

abstract:
  This preprint was split in two and became the first two parts of a four-part
series (arXiv:1405.1956, arXiv:1405:1955, and two in preparation). The
remaining relevance of this preprint is due to the series of videotaped
lectures (wClips) that are linked within.


title: Higgs phenomenology in Type-I 2HDM with U(1)_H Higgs gauge symmetry

abstract:
  It is well known that generic two-Higgs-doublet models (2HDMs) suffer from
potentially large Higgs-mediated flavor-changing neutral current (FCNC)
problem, unless additional symmetries are imposed on the Higgs fields thereby
respecting the Natural Flavor Conservation Criterion (NFC) by Glashow and
Weinberg. A common way to respect the NFC is to impose Z_2 symmetry which is
softly broken by a dim-2 operator. Another new way is to introduce local U(1)_H
Higgs flavor symmetry that distinguishes one Higgs doublet from the other. In
this paper, we consider the Higgs phenomenology in Type-I 2HDMs with the U(1)_H
symmetry with the simplest U(1)_H assignments that the SM fermions are all
neutral under U(1)_H, and we make detailed comparison with the ordinary Type-I
2HDM. After imposing various constraints such as vacuum stability and
perturbativity as well as the electroweak precision observables and collider
search bounds on charged Higgs boson, we find that the allowed Higgs signal
strengths in our model are much broader than those in the ordinary Type-I 2HDM,
because of newly introduced U(1)_H-charged singlet scalar and U(1)_H gauge
boson. Still the ATLAS data on gg to h to gamma gamma cannot be accommodated.
Our model could be distinguished from the ordinary 2HDM with the Z_2 symmetry
in a certain parameter region and some channels. If the couplings of the new
boson turn out to be close to those in the SM, it would be essential to search
for extra U(1)_H gauge boson and/or one more neutral scalar boson to
distinguish two models.


title:
A computational model for histone mark propagation reproduces the
  distribution of heterochromatin in different human cell types

abstract:
  Chromatin is a highly compact and dynamic nuclear structure that consists of
DNA and associated proteins. The main organizational unit is the nucleosome,
which consists of a histone octamer with DNA wrapped around it. Histone
proteins are implicated in the regulation of eukaryote genes and they carry
numerous reversible post-translational modifications that control DNA-protein
interactions and the recruitment of chromatin binding proteins.
Heterochromatin, the transcriptionally inactive part of the genome, is densely
packed and contains histone H3 that is methylated at Lys 9 (H3K9me). The
propagation of H3K9me in nucleosomes along the DNA in chromatin is antagonizing
by methylation of H3 Lysine 4 (H3K4me) and acetylations of several lysines,
which is related to euchromatin and active genes. We show that the related
histone modifications form antagonized domains on a coarse scale. These histone
marks are assumed to be initiated within distinct nucleation sites in the DNA
and to propagate bi-directionally. We propose a simple computer model that
simulates the distribution of heterochromatin in human chromosomes. The
simulations are in agreement with previously reported experimental observations
from two different human cell lines. We reproduced different types of barriers
between heterochromatin and euchromatin providing a unified model for their
function. The effect of changes in the nucleation site distribution and of
propagation rates were studied. The former occurs mainly with the aim of
(de-)activation of single genes or gene groups and the latter has the power of
controlling the transcriptional programs of entire chromosomes. Generally, the
regulatory program of gene transcription is controlled by the distribution of
nucleation sites along the DNA string.


title: Generalized 4th Appelrot class: phase topology

abstract:
  The article continues the author's publication in [Mech. Tverd. Tela, No. 35,
2005 and No. 38, 2008], in which we investigate the integrable dynamical system
induced on one four-dimensional submanifold of the phase space of the problem
of a rigid body motion in a double force field. When the intensity of one of
the fields tends to zero this systems turns into the family of the espesially
remarkable motions of the Kowalevski top belonging to the 4th Appelrot class.
We introduce a method to describe the phase topology in the case when algebraic
dependency is known of the phase variables in terms of separation variables.
This method is based on some construction with Boolean vector functions. For
the considered system with two degrees of freedom we fulfil the rough
topological analysis.


title:
Absence of split pairs in the cross-correlations of a highly transparent
  normal metal-superconductor-normal metal electron beam splitter

abstract:
  The nonlocal conductance and the current cross-correlations are investigated
within scattering theory for three-terminal normal metal-superconductor-normal
metal (NSN) hybrid structures. The positive cross-correlations at high
transparency found by M\'elin, Benjamin and Martin [Phys. Rev. B 77, 094512
(2008)] are not due to crossed Andreev reflection. On the other hand, local
processes can be enhanced by reflectionless tunneling but this mechanism has
little influence on nonlocal processes and on current cross-correlations.
Therefore Cooper pair splitting cannot be enhanced by reflectionless tunneling.
Overall, this shows that NSN structures with highly transparent or effectively
highly transparent interfaces are not suited to experimentally producing
entangled split pairs of electrons.


title:
On the zeros of the second derivative of the Riemann zeta function under
  the Riemann hypothesis

abstract:
  The number of zeros and the distribution of the real part of non-real zeros
of the derivatives of the Riemann zeta function have been investigated by
Berndt, Levinson, Montgomery, and Akatsuka. Berndt, Levinson, and Montgomery
investigated the general case, meanwhile Akatsuka gave sharper estimates for
the first derivative of the Riemann zeta function under the truth of the
Riemann hypothesis. In this paper, we extend the results of Akatsuka to the
second derivative of the Riemann zeta function.


title:
Group classification of variable coefficient generalized Kawahara
  equations

abstract:
  An exhaustive group classification of variable coefficient generalized
Kawahara equations is carried out. As a result, we derive new variable
coefficient nonlinear models admitting Lie symmetry extensions. All
inequivalent Lie reductions of these equations to ordinary differential
equations are performed. We also present some examples on the construction of
exact and numerical solutions.


title: The K-theoretical range of Cuntz-Krieger algebras

abstract:
  We augment Restorff's classification of purely infinite Cuntz-Krieger
algebras by describing the range of his invariant on purely infinite
Cuntz-Krieger algebras. We also describe its range on purely infinite graph
C*-algebras with finitely many ideals, and provide 'unital' range results for
purely infinite Cuntz-Krieger algebras and unital purely infinite graph
C*-algebras.


title:
A Low-Voltage, Low-Power 4-bit BCD Adder, designed using the Clock Gated
  Power Gating, and the DVT Scheme

abstract:
  This paper proposes a Low-Power, Energy Efficient 4-bit Binary Coded Decimal
(BCD) adder design where the conventional 4-bit BCD adder has been modified
with the Clock Gated Power Gating Technique. Moreover, the concept of DVT
(Dual-vth) scheme has been introduced while designing the full adder blocks to
reduce the Leakage Power, as well as, to maintain the overall performance of
the entire circuit. The reported architecture of 4-bit BCD adder is designed
using 45 nm technology and it consumes 1.384 {\mu}Watt of Average Power while
operating with a frequency of 200 MHz, and a Supply Voltage (Vdd) of 1 Volt.
The results obtained from different simulation runs on SPICE, indicate the
superiority of the proposed design compared to the conventional 4-bit BCD
adder. Considering the product of Average Power and Delay, for the operating
frequency of 200 MHz, a fair 47.41 % reduction compared to the conventional
design has been achieved with this proposed scheme.


title:
The way to reduce electrical charge of a droplet dispensed from a
  pipette tip

abstract:
  Recently, our group reported that an any aqueous droplet dispensed from a
pipette tip has considerable amount of electrical charge. This natural
electrical charge of a droplet could cause undesired, unfamiliar experimental
results. Since the origin of the charge of a droplet is related to the pipette
tip material, we modified the inside material of the pipette tip with
poly(dimethylsiloxane)-graphene nanocomposites. The droplets dispensed from the
modified pipette tip has lower electrical charge than that from the common
pipette tip. We compare the experimental results with the droplets from common
pipette tip and modified pipette tip. This fluid dynamics video includes the
principle of the spontaneous electrification of the droplet and the results of
the droplet in oil experiments.


title: Global gradient bounds for the parabolic p-Laplacian system

abstract:
  A by now classical result due to DiBenedetto states that the spatial gradient
of solutions to the parabolic $p$-Laplacian system is locally H\"older
continuous in the interior. However, the boundary regularity is not yet well
understood. In this paper we prove a boundary $L^\infty$-estimate for the
spatial gradient $Du$ of solutions to the parabolic $p$-Laplacian system
\begin{equation*} \partial_t u - \Div \big(|Du|^{p-2}Du\big) = 0 \quad\mbox{in
$\Omega\times(0,T)$} \end{equation*} for $p\ge 2$, together with a quantitative
estimate. In particular, this implies the global Lipschitz regularity of
solutions. The result continues to hold for the so called asymptotically
regular parabolic systems.


title:
High Performance Piezoelectric Devices Based on Aligned Arrays of
  Nanofibers of Poly[(vinylidenefluoride-co-trifluoroethylene]

abstract:
  Multifunctional capability, flexible design, rugged lightweight construction,
and self-powered operation are desired attributes for electronics that directly
interface with the human body or with advanced robotic systems. For these and
related applications, piezoelectric materials, in forms that offer the ability
to bend and stretch, are attractive for pressure/force sensors and mechanical
energy harvesters. In this paper we introduce a large area, flexible
piezoelectric material that consists of sheets of electrospun fibers of the
polymer poly[(vinylidenefluoride-co-trifluoroethylene]. The flow and mechanical
conditions associated with the spinning process yield free-standing,
three-dimensional architectures of aligned arrangements of such fibers, in
which the polymer chains adopt strongly preferential orientations. The
resulting material offers exceptional piezoelectric characteristics, to enable,
as an example, ultra-high sensitivity for measuring pressure, even at
exceptionally small values (0.1 Pa). Quantitative analysis provides detailed
insights into the pressure sensing mechanisms, and engineering design rules.
Applications range from self-powered micro-mechanical elements, to
self-balancing robots and sensitive impact detectors.


title: An Anti-Perfect Dynamo Result

abstract:
  It is shown that if the flow vector is a coordinate basis vector, then
perfect dynamo action is not possible, regardless of whether the steady flow is
compressible. Criteria determining the basis vector property are found to be
expressible in terms of Lie derivatives, and construction of basis vector sets
is straightforward.


title: Black-box optimization using geodesics in statistical manifolds

abstract:
  Information geometric optimization (IGO) is a general framework for
stochastic optimization problems aiming at limiting the influence of arbitrary
parametrization choices. The initial problem is transformed into the
optimization of a smooth function on a Riemannian manifold, defining a
parametrization-invariant first order differential equation. However, in
practice, it is necessary to discretize time, and then, parametrization
invariance holds only at first order in the step size.
  We define the Geodesic IGO update (GIGO), which uses the Riemannian manifold
structure to obtain an update entirely independent from the parametrization of
the manifold. We test it with classical objective functions.
  Thanks to Noether's theorem from classical mechanics, we find an efficient
way to write a first order differential equation satisfied by the geodesics of
the statistical manifold of Gaussian distributions, and thus to compute the
corresponding GIGO update. We then compare GIGO, pure rank-$\mu$ CMA-ES
\cite{CMATuto} and xNES \cite{xNES} (two previous algorithms that can be
recovered by the IGO framework), and show that while the GIGO and xNES updates
coincide when the mean is fixed, they are different in general, contrary to
previous intuition. We then define a new algorithm (Blockwise GIGO) that
recovers the xNES update from abstract principles.


title:
Numerical evaluation of the three-point scalar-tensor cross-correlations
  and the tensor bi-spectrum

abstract:
  Utilizing the Maldacena formalism and extending the earlier efforts to
compute the scalar bi-spectrum, we construct a numerical procedure to evaluate
the three-point scalar-tensor cross-correlations as well as the tensor
bi-spectrum in single field inflationary models involving the canonical scalar
field. We illustrate the accuracy of the adopted procedure by comparing the
numerical results with the analytical results that can be obtained in the
simpler cases of power law and slow roll inflation. We also carry out such a
comparison in the case of the Starobinsky model described by a linear potential
with a sudden change in the slope, which provides a non-trivial and interesting
(but, nevertheless, analytically tractable) scenario involving a brief period
of deviation from slow roll. We then utilize the code we have developed to
evaluate the three-point correlation functions of interest (and the
corresponding non-Gaussianity parameters that we introduce) for an arbitrary
triangular configuration of the wavenumbers in three different classes of
inflationary models which lead to features in the scalar power spectrum, as
have been recently considered by the Planck team. We also discuss the
contributions to the three-point functions during preheating in inflationary
models with a quadratic minimum. We conclude with a summary of the main results
we have obtained.


title: An Efficient Index for Visual Search in Appearance-based SLAM

abstract:
  Vector-quantization can be a computationally expensive step in visual
bag-of-words (BoW) search when the vocabulary is large. A BoW-based appearance
SLAM needs to tackle this problem for an efficient real-time operation. We
propose an effective method to speed up the vector-quantization process in
BoW-based visual SLAM. We employ a graph-based nearest neighbor search (GNNS)
algorithm to this aim, and experimentally show that it can outperform the
state-of-the-art. The graph-based search structure used in GNNS can efficiently
be integrated into the BoW model and the SLAM framework. The graph-based index,
which is a k-NN graph, is built over the vocabulary words and can be extracted
from the BoW's vocabulary construction procedure, by adding one iteration to
the k-means clustering, which adds small extra cost. Moreover, exploiting the
fact that images acquired for appearance-based SLAM are sequential, GNNS search
can be initiated judiciously which helps increase the speedup of the
quantization process considerably.