  CO is one of the most abundant ice components on interstellar dust grains.
When it is mixed with amorphous solid water (ASW) or located on its surface, an
absorption band of CO at 2152 cm$^{-1}$ is always present in laboratory
measurements. This spectral feature is attributed to the interaction of CO with
dangling-OH bonds (dOH) in ASW. However, this band is absent in observational
spectra of interstellar ices. This raises the question whether CO forms a
relatively pure layer on top of ASW or is in close contact with ASW, but not
via dangling bonds. We aim to determine whether the incorporation of NH$_3$ or
CO$_2$ into ASW blocks the dOH and therefore reduces the 2152 cm$^{-1}$ band.
We performed laboratory experiments to simulate the layered structure of the
ice mantle, that is, we grew CO ice on top of 1) pure ASW, 2)
NH$_3$:H$_2$O=10:100 mixed ice, and 3) CO$_2$:H$_2$O=20:100 mixed ice. Infrared
spectra were measured to quantify the strength of the 2152 cm$^{-1}$ band. In
addition, a second set of experiments were performed to determine how the
incorporation of NH$_3$ into ASW affects the dOH band. We found that annealing
the ice reduces the 2152 cm$^{-1}$ band and that NH$_3$ blocks the dOH on ASW
surface and therefore reduces the 2152 cm$^{-1}$ band more effectively than
CO$_2$. We suggest that this difference between NH$_3$ and CO$_2$ can be
ascribed to the polarity of the guest molecule (NH$_3$ is a polar species,
whereas CO$_2$ is apolar). The polarity implies that the formation of an H-bond
between the N atom of ammonia and the dOH is a barrier-less reaction. We also
determined the pore surface area of the ice mixtures as a function of the
annealing temperature, and found that the nondetection of 2152 cm$^{-1}$ band
does not necessarily exclude the possibility of a porous ice mantle.


  Quantum entanglement is the key resource for quantum information processing.
Device-independent certification of entangled states is a long standing open
question, which arouses the concept of self-testing. The central aim of
self-testing is to certify the state and measurements of quantum systems
without any knowledge of their inner workings, even when the used devices
cannot be trusted. Specifically, utilizing Bell's theorem, it is possible to
place a boundary on the singlet fidelity of entangled qubits. Here, beyond this
rough estimation, we experimentally demonstrate a complete self-testing process
for various pure bipartite entangled states up to four dimensions, by simply
inspecting the correlations of the measurement outcomes. We show that this
self-testing process can certify the exact form of entangled states with
fidelities higher than 99.9% for all the investigated scenarios, which
indicates the superior completeness and robustness of this method. Our work
promotes self-testing as a practical tool for developing quantum techniques.


  For a graph G with real weights assigned to the vertices (edges), the MAX
H-SUBGRAPH problem is to find an H-subgraph of G with maximum total weight, if
one exists. The all-pairs MAX H-SUBGRAPH problem is to find for every pair of
vertices u,v, a maximum H-subgraph containing both u and v, if one exists. Our
main results are new strongly polynomial algorithms for the all-pairs MAX
H-SUBGRAPH problem for vertex weighted graphs. We also give improved algorithms
for the MAX-H SUBGRAPH problem for edge weighted graphs, and various related
problems, including computing the first k most significant bits of the distance
product of two matrices. Some of our algorithms are based, in part, on fast
matrix multiplication.


  Generalized \dK modules are introduced to solve an open problem: the odd
Ext-module $\Eod(M)$ of a \dK module $M$ over a $d$-Koszul algebra $\m$ is a \K
module over the even Yoneda algebra $\Eev(\m)$.


  A semigroupoid is a set equipped with a partially defined associative
operation. Given a semigroupoid \Lambda we construct a C*-algebra C*(\Lambda)
from it. We then present two main examples of semigroupoids, namely the Markov
semigroupoid associated to an infinite 0-1 matrix, and the semigroupoid
associated to a row-finite higher-rank graph without sources. In both cases the
semigroupoid C*-algebra is shown to be isomorphic to the algebras usually
attached to the corresponding combinatorial object, namely the Cuntz-Krieger
algebras and the higher-rank graph C*-algebras, respectively. In the case of a
higher-rank graph (\Lambda,d), it follows that the dimension function d is
superfluous for defining the corresponding C*-algebra.


  Here we prove unitarity of the recently found fourth-order self-dual model of
spin-2 by investigating the analytic structure of its propagator. The model
describes massive particles of helicity +2 (or -2) in $D=2+1$ and corresponds
to the quadratic truncation of a higher derivative topologically massive
gravity about a flat background. It is an intriguing example of a theory where
a term in the propagator of the form $1/\lbrack\Box^2 (\Box - m^2)\rbrack $
does not lead to ghosts. The crucial role of the linearized Weyl symmetry in
getting rid of the ghosts is pointed out. We use a peculiar pair of gauge
conditions which fix the linearized reparametrizations and linearized Weyl
symmetries separetely.


  Precisely engineered tunnel junctions exhibit a long sought effect that
occurs when the energy of the electron is comparable to the potential energy of
the tunneling barrier. The resistance of metal-insulator-metal tunnel junctions
oscillates with an applied voltage when electrons that tunnel directly into the
barrier's conduction band interfere upon reflection at the classical turning
points: the insulator-metal interface, and the dynamic point where the incident
electron energy equals the potential barrier inside the insulator. A model of
tunneling between free electron bands using the exact solution of the
Schroedinger equation for a trapezoidal tunnel barrier qualitatively agrees
with experiment.


  One of the current challenges in nanoscience is tailoring phononic devices,
such as thermal regulators and thermal computing. This has long been a rather
elusive task because the thermal-switching ratio is not as high as electronic
analogs. Mapping from a topological kirigami assembly, nitrogen-doped porous
graphene metamaterials on the nanoscale are inversely designed with a
thermal-switching ratio of 27.79, which is more than double the value of
previous work. We trace this behavior to the chiral folding-unfolding
deformation, resulting in a metal-insulator transition. This study provides a
nanomaterial design paradigm to bridge the gap between kinematics and
functional metamaterials that motivates the development of high-performance
thermal regulators.


  In this paper, we will investigate the consequences of loop quantum
gravitational modifications on the formation of naked singularities. The loop
quantum gravitational effects will be incorporated in the collapsing system
using gravity's rainbow. This will be done by using rainbow functions, which
are constructed from loop quantum gravitational modifications to the energy
momentum dispersion. It will be observed that this modification will prevent
the formation of naked singularity. Thus, such a modification can ensures that
the weak cosmic censorship hypothesis will hold for any collapsing system.


  In 1972, at a symposium celebrating the 70th birthday of Paul Dirac, John
Wheeler proclaimed that "the framework falls down for everything that one has
ever called a law of physics". Responsible for this "breakage [...] among the
laws of physics" was the general theory of relativity, more specifically its
prediction of massive stars gravitationally collapsing to "black holes", a term
Wheeler himself had made popular some years earlier. In our paper, we
investigate how Wheeler reached the conclusion that gravitational collapse
calls into question the lawfulness of physics and how, subsequently, he tried
to develop a new worldview, rethinking in his own way the lessons of quantum
mechanics as well as drawing inspiration from other disciplines, not least
biology.


  Optical tweezers are a versatile tool that can be used to manipulate small
particles including both motile and non-motile bacteria and cells. The
orientation of a non-spherical particle within a beam depends on the shape of
the particle and the shape of the light field. By using multiple beams,
sculpted light fields or dynamically changing beams, it is possible to control
the orientation of certain particles. In this paper we discuss the orientation
of the rod-shaped bacteria Escherichia coli (E. coli) using dynamically
shifting annular beam optical tweezers. We begin with examples of different
beams used for the orientation of rod-shaped particles. We discuss the
differences between orientation of motile and non-motile particles, and explore
annular beams and the circumstances when they may be beneficial for
manipulation of non-spherical particles or cells. Using simulations we map out
the trajectory the E. coli takes. Estimating the trap stiffness along the
trajectory gives us an insight into how stable an intermediate rotation is with
respect to the desired orientation. Using this method, we predict and
experimentally verify the change in the orientation of motile E. coli from
vertical to near-horizontal with only one intermediate step. The method is not
specific to exploring the orientation of particles and could be easily extended
to quantify the stability of an arbitrary particle trajectory.


  Results of quasi-classical molecular dynamics simulations of the quantum
electron gas are reported. Quantum effects corresponding to the Pauli and the
Heisenberg principle are modeled by an effective momentum-dependent
Hamiltonian. The velocity autocorrelation functions and the dynamic structure
factors have been computed. A comparison with theoretical predictions was
performed.


  We propose a general design strategy based on genetic optimization to realize
asymmetric reflectivity in periodic and non-periodic planar structures
containing dielectric and gain-loss layers. By means of an optimization
algorithm, it is possible to design the imaginary (or real) part of the complex
permittivity distribution from any given and arbitrary real (or imaginary)
permittivity distribution, i.e to create non-Hermitian potentials intended to
achieve on-demand light transport for a selected spectral range. Indeed, the
asymmetric response of the obtained complex permittivity distribution is
directly related to its area in the complex permittivity plane. In particular,
unidirectional light reflection can be designed in such a way that it switches
from left to right (or vice versa) depending on the operating frequency.
Moreover, such controllable unidirectional reflectivity can be realized using a
stack of dielectric layers while keeping the refractive index and gain-loss
within realistic values.


  Thermodynamic properties of strange quark matter in strong magnetic fields
$H$ up to $10^{20}$ G are considered within the MIT bag model at zero
temperature implying the constraints of total baryon number conservation,
charge neutrality and chemical equilibrium. The pressure anisotropy, exhibiting
in the difference between the pressures along and perpendicular to the field
direction, becomes essential at $H>H_{th}$, with the estimate
$10^{17}<H_{th}\lesssim10^{18}$ G. The longitudinal pressure vanishes in the
critical field $H_c$, which can be somewhat less or larger than $10^{18}$ G,
depending on the total baryon number density and bag pressure. As a result, the
longitudinal instability occurs in strange quark matter, which precludes: (1) a
significant drop in the content of $s$ quarks, which, otherwise, could happen
at $H\sim10^{20}$ G; (2) the appearance of positrons in weak processes in a
narrow interval near $H\sim2\cdot10^{19}$ G (replacing electrons). The
occurrence of the longitudinal instability leaves the possibility only for
electrons to reach a fully polarized state, while for all quark flavors the
polarization remains mild even for the fields near $H_c$. The anisotropic
equation of state is determined under the conditions relevant to the interiors
of magnetars.


  Many real-world networks have high clustering among vertices: vertices that
share neighbors are often also directly connected to each other. A network's
clustering can be a useful indicator of its connectedness and community
structure. Algorithms for generating networks with high clustering have been
developed, but typically rely on adding or removing edges and nodes, sometimes
from a completely empty network. Here, we introduce algorithms that create a
highly clustered network by starting with an existing network and rearranging
edges, without adding or removing them; these algorithms can preserve other
network properties even as the clustering increases. They rely on local
rewiring rules, in which a single edge changes one of its vertices in a way
that is guaranteed to increase clustering. This greedy step can be applied
iteratively to transform a random network into a form with much higher
clustering. Additionally, the algorithms presented grow a network's clustering
faster than they increase its path length, meaning that network enters a regime
of comparatively high clustering and low path length: a small world. These
algorithms may be a basis for how real-world networks rearrange themselves
organically to achieve or maintain high clustering and small-world structure.


  In the last 30 years it was found that many combinatorial systems undergo
phase transitions. One of the most important examples of these can be found
among the random k-satisfiability problems (often referred to as k-SAT), asking
whether there exists an assignment of Boolean values satisfying a Boolean
formula composed of clauses with k random variables each. The random 3-SAT
problem is reported to show various phase transitions at different critical
values of the ratio of the number of clauses to the number of variables. The
most famous of these occurs when the probability of finding a satisfiable
instance suddenly drops from 1 to 0. This transition is associated with a rise
in the hardness of the problem, but until now the correlation between any of
the proposed phase transitions and the hardness is not totally clear. In this
paper we will first show numerically that the number of solutions universally
follows a lognormal distribution, thereby explaining the puzzling question of
why the number of solutions is still exponential at the critical point.
Moreover we provide evidence that the hardness of the closely related problem
of counting the total number of solutions does not show any phase
transition-like behavior. This raises the question of whether the probability
of finding a satisfiable instance is really an order parameter of a phase
transition or whether it is more likely to just show a simple sharp threshold
phenomenon. More generally, this paper aims at starting a discussion where a
simple sharp threshold phenomenon turns into a genuine phase transition.


  The top quark, the heaviest quark and, indeed, the heaviest elementary
particle known today, constitutes a novel probe of the long-lived medium in
quark-gluon phase which, as expected, can be produced even in light nuclei
collisions at ultra-high energies. Some distinctive features are considered for
particle production in the top sector in ultra-high energy domain. The
antitop-top pair production is studied within the quantum chromodynamics and
effective field theory approach used for calculations of total partonic cross
sections. Predictions for all observables are computed at NNLO in quantum
chromodynamics and at LO in effective field theory. These quantitative results
can be important for both the future collider experiments at center-of-mass
energy frontier and the improvement of the phenomenological models for
development of the cosmic ray cascades in ultra-high energy domain. Thus the
study allows the better understanding of heavy particle production and
emphasizes the exciting interrelation between the high-energy physics on
accelerators and ultra-high energy cosmic ray measurements.


  ALICE (A Large Ion Collider Experiment) is the dedicated heavy ion experiment
at the Large Hadron Collider at CERN. The main tracking device of ALICE is a
large volume TPC.
  The milestones of the TPC commissioning as well as the current status of the
detector calibration are presented. The obtained resolutions in transverse
momentum, position as well as in specific energy loss (dE/dx) are presented and
results from noise and electron drift velocity measurements are addressed.


  Blocking and shadowing is one of the key effects in designing and evaluating
a thermal central receiver solar tower plant. Therefore it is convenient to
develop efficient algorithms to compute the area of an heliostat blocked or
shadowed by the rest of the field. In this paper we explore the possibility of
using very efficient clipping algorithms developed for the video game and
imaging industry to compute the blocking and shadowing efficiency of a solar
thermal plant layout. We propose an algorithm valid for arbitrary position,
orientation and size of the heliostats. This algorithm turns out to be very
accurate, free of assumptions and fast. We show the feasibility of the use of
this algorithm to the optimization of a solar plant by studying a couple of
examples in detail.


  Quantum interfaces between polarized atomic ensembles and coherent states of
light, applied recently to manipulate bipartite and multipartite entanglement,
are revisited by means of a continuous-variable formalism. The explicit use of
the continuous-variable formalism facilitates significantly the analysis of
entanglement between different modes, reducing it to the study of the
properties of a final covariance matrix which can be found analytically.
Furthermore, it allows to study matter-light interfaces for mixed states,
adapting the formalism to the experimental situations in which the initial
prepared Gaussian states are, unavoidably, affected by a certain amount of
noise. A multipartite scenario, leading to the generation of macroscopic
cluster states is presented and analyzed in detail within this formalism.


  A language $L$ over an alphabet $\Sigma$ is prefix-convex if, for any words
$x,y,z\in\Sigma^*$, whenever $x$ and $xyz$ are in $L$, then so is $xy$.
Prefix-convex languages include right-ideal, prefix-closed, and prefix-free
languages. We study complexity properties of prefix-convex regular languages.
In particular, we find the quotient/state complexity of boolean operations,
product (concatenation), star, and reversal, the size of the syntactic
semigroup, and the quotient complexity of atoms. For binary operations we use
arguments with different alphabets when appropriate; this leads to higher tight
upper bounds than those obtained with equal alphabets. We exhibit most complex
prefix-convex languages that meet the complexity bounds for all the measures
listed above.


  We consider a sufficiently smooth semi-stable holomorphic vector bundle over
a compact K\"ahler manifold. Assuming the automorphism group of its graded
object to be abelian, we provide a semialgebraic decomposition of a
neighbourhood of the polarisation in the K\"ahler cone into chambers
characterising (in)stability. For a path in a stable chamber converging to the
initial polarisation, we show that the associated HYM connections converge to
an HYM connection on the graded object.


  Following a strategy suggested by Michel--Venkatesh, we study the cubic
moment of automorphic $L$-functions on $\operatorname{PGL}_2$ using regularized
diagonal periods of products of Eisenstein series. Our main innovation is to
produce vectors whose integral transforms achieve arbitrarily weighted moments.
Applications include general Motohashi-type identities and Weyl-type subconvex
bounds for some families of $L$-functions, extending some results of
Conrey--Iwaniec and Petrow--Young to the number field setting. We deduce
improved estimates for representation numbers of ternary quadratic forms over
number fields and for the prime geodesic theorem on arithmetic hyperbolic
$3$-folds.


  Morphisms in the linear category A of Jacobi diagrams in handlebodies give
rise to interesting contravariant functors on the category gr of
finitely-generated free groups, encoding part of the composition structure of
the category A. These functors correspond, via an equivalence of categories
given by Powell, to functors given by beaded open Jacobi diagrams. We study the
polynomiality of these functors and whether they are outer functors. These
results are inspired by and generalize previous results obtained by Katada.


  We propose a definition of a Poincar\'e algebra for a two dimensional
space--time with one discretized dimension. This algebra has the structure of a
Hopf algebra. We use the link between Onsager's uniformization of the Ising
model and the dispersion relation of a free particle in this space--time,
together with the rapidity representation of the quantum deformation of the
Poincar\'e enveloping algebra.


  We apply the Wiener Hermite (WH) expansion to the non-linear evolution of
Large-Scale Structure, and obtain an approximate expression for the matter
power spectrum in full order of the expansion. This method allows us to expand
any random function in terms of an orthonormal bases in space of random
functions in such a way that the first order of the expansion expresses the
Gaussian distribution, and others are the deviation from the Gaussianity. It is
proved that the Wiener Hermite expansion is mathematically equivalent with the
$\Gamma$-expansion approach in the Renormalized Perturbation Theory (RPT).
While an exponential behavior in the high-$k$ limit has been proved for the
mass density and velocity fluctuations of Dark Matter in the RPT, we reprove
the behavior in the context of the Wiener Hermite expansion using the result of
Standard Perturbation Theory (SPT). We propose a new approximate expression for
the matter power spectrum which interpolates the low-$k$ expression
corresponding to 1-loop level in SPT and the high-$k$ expression obtained by
taking a high-$k$ limit of the WH expansion. The validity of our prescription
is specifically verified by comparing with the 2-loop solutions of the SPT. The
proposed power spectrum agrees with the result of $N$-body simulation with the
accuracy better than 1% or 2% in a range of the BAO scales, where the wave
number is about $k= 0.2 \sim 0.4$ $h{\rm Mpc^{-1}}$ at $z=0.5-3.0$. This
accuracy is comparable to or slightly less than the ones in the Closure Theory
whose the fractional difference from N body result is within 1%. A merit of our
method is that the computational time is very short because only single and
double integrals are involved in our solution.


  The question whether P equals NP revolves around the discrepancy between
active production and mere verification by Turing machines. In this paper, we
examine the analogous problem for finite transducers and automata. Every
nondeterministic finite transducer defines a binary relation associating each
input word with all output words that the transducer can successfully produce
on the given input. Finite-valued transducers are those for which there is a
finite upper bound on the number of output words that the relation associates
with every input word. We characterize finite-valued, functional, and
unambiguous nondeterministic transducers whose relations can be verified by a
deterministic two-tape automaton, show how to construct such an automaton if
one exists, and prove the undecidability of the criterion.


  In the past decades mathematical optimization has found its way into
radiation therapy and has made profound practice changing impact. Today,
virtually all advanced treatment delivery methods, such as IMRT, VMAT,
tomotherapy, LDR/HDR brachytherapy, proton therapy, are based on some form of
optimization approach that changes the treatment variables (beam intensities,
multileaf collimator shapes, beam angles, dwell times and seed or source
positions) in the planning computer using an optimization algorithm, until the
best value of the treatment (planning) objective has been found. It is fair to
say though that a truly optimal radiation treatment plan remains elusive. The
reasons for that include difficulties in defining meaningful planning
objectives and constraints in mathematical terms, various uncertainties in the
planning and delivery process, and the inability of optimization algorithms to
find the true optimum. Radiation therapy optimization therefore remains an
active field of research.


  We review minimal realistic grand unified models based on $SU(5)$ and
$SO(10)$ gauge groups. The models with small Higgs representations and higher
dimensional operators - under the assumption of no cancellations in proton
decay amplitudes - predict nearby oases with new light particles. Two of them
stand out: real fermion and scalar weak triplets. The former generates
dynamically neutrino Majorana mass through the so-called type III seesaw
mechanism, while the latter naturally gets a small vacuum expectation value and
thus generically modifies $W$-boson mass. On the contrary, the renormalisable
versions of these theories fail to determine the particle spectra. In
particular, in the renormalisable version of the $SO(10)$ theory the mass of
the right-handed gauge boson - normally assumed (and allowed) to lie far in the
desert - could be even accessible at the LHC. Last but not least, we show that
in the minimal supersymmetric $SU(5)$ theory all the superpartners can lie
orders of magnitude above the weak scale, unless one requires strict
naturalness. Thus, the so-called split supersymmetry does not imply any light
states.


  In the first part of this paper, we derive the general replica equations that
describe infinite-dimensional hard spheres at any level of replica symmetry
breaking (RSB) and in particular in the fullRSB scheme. We show that these
equations are formally very similar to the ones that have been derived for spin
glass models, thus showing that the analogy between spin glasses and structural
glasses conjectured by Kirkpatrick, Thirumalai, and Wolynes is realized in a
strong sense in the mean field limit. We also suggest how the computation could
be generalized in an approximate way to finite dimensional hard spheres. In the
second part of the paper, we discuss the solution of these equations and we
derive from it a number of physical predictions. We show that, below the
Gardner transition where the 1RSB solution becomes unstable, a fullRSB phase
exists and we locate the boundary of the fullRSB phase. Most importantly, we
show that the fullRSB solution predicts correctly that jammed packings are
isostatic, and allows one to compute analytically the critical exponents
associated with the jamming transition, which are missed by the 1RSB solution.
We show that these predictions compare very well with numerical results.


  In some short gamma-ray bursts, precursor flares occurring $\sim$ seconds
prior to the main episode have been observed. These flares may then be
associated with the last few cycles of the inspiral when the orbital frequency
is a few hundred Hz. During these final cycles, tidal forces can resonantly
excite quasi-normal modes in the inspiralling stars, leading to a rapid
increase in their amplitude. It has been shown that these modes can exert
sufficiently strong strains onto the neutron star crust to instigate yieldings.
Due to the typical frequencies of $g$-modes being $\sim 100\text{ Hz}$, their
resonances with the orbital frequency match the precursor timings and warrant
further investigation. Adopting realistic equations of state and solving the
general-relativistic pulsation equations, we study $g$-mode resonances in
coalescing quasi-circular binaries, where we consider various stellar rotation
rates, degrees of stratification, and magnetic field structures. We show that
for some combination of stellar parameters, the resonantly excited $g_1$- and
$g_2$-modes may lead to crustal failure and trigger precursor flares.


  Personal Rapid Transit (PRT) is a promising form of urban transport. Its
operation consists in the use of small unmanned vehicles which convey the
passengers among stations within a dedicated network. Various aspects of the
PRT network performance are frequently evaluated using the discrete-event
simulation. The paper supports the need of establishing some reference models
for the simulation of PRT networks, targeted mainly towards the needs of the
research on network management algorithms. Three models of such PRT network
models are proposed and discussed. The presented models can play the role of
benchmarks which would be very useful for comparative evaluation of heuristic
control algorithms, developed by different research groups.


  We consider the thermodynamics of chemical coupling from the viewpoint of
free energy transduction efficiency. In contrast to an external
parameter-driven stochastic energetics setup, the dynamic change of the
equilibrium distribution induced by chemical coupling, adopted, for example, in
biological systems, is inevitably an autonomous process. We found that the
efficiency is bounded by the ratio between the non-symmetric and the
symmetrized Kullback-Leibler distance, which is significantly lower than unity.
Consequences of this low efficiency are demonstrated in the simple two-state
case, which serves as an important minimal model for studying the energetics of
biomolecules.


  We study the effect of the mutant's degree on the fixation probability,
extinction and fixation times, in the Moran process on Erd\"{o}s-R\'{e}nyi and
Barab\'{a}si-Albert graphs. We performed stochastic simulations and use
mean-field type approximations to obtain analytical formulas. We showed that
the initial placement of a mutant has a significant impact on the fixation
probability and extinction time, while it has no effect on the fixation time.
In both types of graphs, an increase in the degree of a initial mutant results
in a decreased fixation probability and a shorter time to extinction.


  We will review the crucial AGILE gamma-ray SNR observations focusing on the
evidence of hadronic cosmic-ray acceleration that has been obtained so far. We
discuss data on SNR IC443, W28 and W44. We show that in all cases a consistent
model of hadronic acceleration and interaction with gaseous surroundings can be
used to successfully explain the quite complex morphology and spectral
characteristics of the sources. AGILE, with its crucially important sensitivity
near 100 MeV, is equipped to prove the existence of pi-zero emission.


  We report a new approach for progressive and well-controlled downsizing of
nanostructures below the 10 nm scale. Low energetic ion beam (Ar+) is used for
gentle surface erosion, progressively shrinking the dimensions with ~ 1 nm
accuracy. The method enables shaping of nanostructure geometry and polishing
the surface. The process is clean room / high vacuum compatible being suitable
for various applications. Apart from technological advantages, the method
enables study of various size phenomena on the same sample between sessions of
ion beam treatment.


  Braneworld cosmology supported by a bulk scalar field with an exponential
potential is developed. A general class of separable backgrounds for both
single and two-brane systems is derived, where the bulk metric components are
given by products of world-volume and bulk coordinates and the world-volumes
represent any anisotropic and inhomogeneous solution to an effective
four-dimensional Brans-Dicke theory of gravity. We deduce a cosmic no hair
theorem for all ever expanding, spatially homogeneous Bianchi world-volumes and
find that the spatially flat and isotropic inflationary scaling solution
represents a late-time attractor when the bulk potential is sufficiently flat.
The dependence of this result on the separable nature of the bulk metric is
investigated by applying the techniques of Hamilton-Jacobi theory to
five-dimensional Einstein gravity. We employ the spatial gradient expansion
method to determine the asymptotic form of the bulk metric up to third-order in
spatial gradients. It is found that the condition for the separable form of the
metric to represent the attractor of the system is precisely the same as that
for the four-dimensional world-volume to isotropize. We also derive the
fourth-order contribution to the Hamilton-Jacobi generating functional.
Finally, we conclude by placing our results within the context of the
holographic approach to braneworld cosmology.


  Simonton is attempting to salvage the Blind Variation Selective Retention
theory of creativity (often referred to as the Darwinian theory of creativity)
by dissociating it from Darwinism. This is a necessary move for complex reasons
outlined in detail elsewhere. However, whether or not one calls BVSR a
Darwinian theory, it is still a variation-and-selection theory.
Variation-and-selection was put forward to solve a certain kind of paradox,
that of how biological change accumulates (that is, over generations, species
become more adapted to their environment) despite being discarded at the end of
each generation (that is, parents don't transmit to offspring knowledge or
bodily changes acquired during their lifetimes, e.g., you don't inherit your
mother's ear piercings). This paradox does not exist with respect to creative
thought. There is no discarding of acquired change when ideas are transmitted
amongst individuals; we share with others modified versions of the ideas we
were exposed to on a regular basis.


  The vulnerability of deep neural networks to small, adversarially designed
perturbations can be attributed to their "excessive linearity." In this paper,
we propose a bottom-up strategy for attenuating adversarial perturbations using
a nonlinear front end which polarizes and quantizes the data. We observe that
ideal polarization can be utilized to completely eliminate perturbations,
develop algorithms to learn approximately polarizing bases for data, and
investigate the effectiveness of the proposed strategy on the MNIST and Fashion
MNIST datasets.


  We establish continuity of the integral representation
$y(t)=x(t)+\int_0^th(y(s)) ds$, $t\ge0$, mapping a function $x$ into a function
$y$ when the underlying function space $D$ is endowed with the Skorohod $M_1$
topology. We apply this integral representation with the continuous mapping
theorem to establish heavy-traffic stochastic-process limits for many-server
queueing models when the limit process has jumps unmatched in the converging
processes as can occur with bursty arrival processes or service interruptions.
The proof of $M_1$-continuity is based on a new characterization of the $M_1$
convergence, in which the time portions of the parametric representations are
absolutely continuous with respect to Lebesgue measure, and the derivatives are
uniformly bounded and converge in $L_1$.


  Let $A$ be an associative algebra over a field of characteristic $\neq 2$
that is generated by a finite collection of nilpotent elements. We prove that
all Lie derived powers of $A$ are finitely generated Lie algebras.


  We reinterpret the generalised Lie derivative of M-theory $E_6$ generalised
geometry as hamiltonian flow on a graded symplectic supermanifold. The
hamiltonian acts as the nilpotent derivative of the tensor hierarchy of
exceptional field theory. This construction is an M-theory analogue of the
Courant algebroid and reveals the $L_\infty$-algebra underlying the tensor
hierarchy.
  The AKSZ construction identifies that same hamiltonian with the lagrangian of
a 7-dimensional generalisation of Chern-Simons theory that reduces to the
M5-brane Wess-Zumino term on 5-brane boundaries. The exercise repeats for the
type IIB $E_5$ generalised geometry and we discuss the relation to the
D3-brane.


  We produce an example of an irreducible discrete subgroup in the product
$SL(2,\R)\times SL(2,\R)$ which is not a lattice. This answers a question asked
in [15].


  Amidst the recent strides in evaluating Large Language Models for Code (Code
LLMs), existing benchmarks have mainly focused on the functional correctness of
generated code, neglecting the importance of their computational efficiency. To
fill the gap, we present Mercury, the first code efficiency benchmark for Code
LLMs. It comprises 1,889 Python tasks, each accompanied by adequate solutions
that serve as real-world efficiency baselines, enabling a comprehensive
analysis of the runtime distribution. Based on the distribution, we introduce a
new metric Beyond, which computes a runtime-percentile-weighted Pass score to
reflect functional correctness and code efficiency simultaneously. On Mercury,
leading Code LLMs can achieve 65% on Pass, while less than 50% on Beyond. Given
that an ideal Beyond score would be aligned with the Pass score, it indicates
that while Code LLMs exhibit impressive capabilities in generating functionally
correct code, there remains a notable gap in their efficiency. Finally, our
empirical experiments reveal that Direct Preference Optimization (DPO) serves
as a robust baseline for enhancing code efficiency compared with Supervised
Fine Tuning (SFT), which paves a promising avenue for future exploration of
efficient code generation. Our code and data are available on GitHub:
https://github.com/Elfsong/Mercury.


  We have begun a survey of the chemical and dynamical properties of the Milky
Way disk as traced by open star clusters. In this first contribution, the
general goals of our survey are outlined and the strengths and limitations of
using star clusters as a Galactic disk tracer sample are discussed. We also
present medium resolution (R ~ 15,0000) spectroscopy of open cluster stars
obtained with the Hydra multi-object spectrographs on the Cerro Tololo
Inter-American Observatory 4-m and WIYN 3.5-m telescopes. Here we use these
data to determine the radial velocities of 3436 stars in the fields of open
clusters within about 3 kpc, with specific attention to stars having proper
motions in the Tycho-2 catalog. Additional radial velocity members (without
Tycho-2 proper motions) that can be used for future studies of these clusters
were also identified. The radial velocities, proper motions, and the angular
distance of the stars from cluster center are used to derive cluster membership
probabilities for stars in each cluster field using a non-parametric approach,
and the cluster members so-identified are used, in turn, to derive the reliable
bulk three-dimensional motion for 66 of 71 targeted open clusters. The high
probability cluster members that we identify help to clarify the
color-magnitude sequences for many of the clusters, and are prime targets for
future echelle resolution spectroscopy as well as astrometric study with the
Space Interferometry Mission (SIM Planetquest).


  Machine translation has recently achieved impressive performance thanks to
recent advances in deep learning and the availability of large-scale parallel
corpora. There have been numerous attempts to extend these successes to
low-resource language pairs, yet requiring tens of thousands of parallel
sentences. In this work, we take this research direction to the extreme and
investigate whether it is possible to learn to translate even without any
parallel data. We propose a model that takes sentences from monolingual corpora
in two different languages and maps them into the same latent space. By
learning to reconstruct in both languages from this shared feature space, the
model effectively learns to translate without using any labeled data. We
demonstrate our model on two widely used datasets and two language pairs,
reporting BLEU scores of 32.8 and 15.1 on the Multi30k and WMT English-French
datasets, without using even a single parallel sentence at training time.


  Large language models (LLMs) can now handle longer sequences of tokens,
enabling complex tasks like book understanding and generating lengthy novels.
However, the key-value (KV) cache required for LLMs consumes substantial memory
as context length increasing, becoming the bottleneck for deployment. In this
paper, we present a strategy called SKVQ, which stands for sliding-window KV
cache quantization, to address the issue of extremely low bitwidth KV cache
quantization. To achieve this, SKVQ rearranges the channels of the KV cache in
order to improve the similarity of channels in quantization groups, and applies
clipped dynamic quantization at the group level. Additionally, SKVQ ensures
that the most recent window tokens in the KV cache are preserved with high
precision. This helps maintain the accuracy of a small but important portion of
the KV cache.SKVQ achieves high compression ratios while maintaining accuracy.
Our evaluation on LLMs demonstrates that SKVQ surpasses previous quantization
approaches, allowing for quantization of the KV cache to 2-bit keys and 1.5-bit
values with minimal loss of accuracy. With SKVQ, it is possible to process
context lengths of up to 1M on an 80GB memory GPU for a 7b model and up to 7
times faster decoding.


  The proposed Earth observation (EO) based value adding system (EO VAS),
hereafter identified as AutoCloud+, consists of an innovative EO image
understanding system (EO IUS) design and implementation capable of automatic
spatial context sensitive cloud/cloud shadow detection in multi source multi
spectral (MS) EO imagery, whether or not radiometrically calibrated, acquired
by multiple platforms, either spaceborne or airborne, including unmanned aerial
vehicles (UAVs). It is worth mentioning that the same EO IUS architecture is
suitable for a large variety of EO based value adding products and services,
including: (i) low level image enhancement applications, such as automatic MS
image topographic correction, co registration, mosaicking and compositing, (ii)
high level MS image land cover (LC) and LC change (LCC) classification and
(iii) content based image storage/retrieval in massive multi source EO image
databases (big data mining).


  We show that the two coproducts of a Markov $L$-coalgebra yield at least two
solutions of the Yang-Baxter equation and thus at least two representations of
braid groups.


  Our recent search for the presence of a magnetic field in the bright early
A-type supergiant HD92207 using FORS2 in spectropolarimetric mode revealed the
presence of a longitudinal magnetic field of the order of a few hundred Gauss.
However, the definite confirmation of the magnetic nature of this object
remained pending due to the detection of short-term spectral variability
probably affecting the position of line profiles in left- and right-hand
polarized spectra. We present new magnetic field measurements of HD92207
obtained on three different epochs in 2013 and 2014 using FORS2 in
spectropolarimetric mode. A 3sigma detection of the mean longitudinal magnetic
field using the entire spectrum, <B_z>_all=104+-34G, was achieved in
observations obtained in 2014 January. At this epoch, the position of the
spectral lines appeared stable. Our analysis of spectral line shapes recorded
in opposite circularly polarized light, i.e. in light with opposite sense of
rotation, reveals that line profiles in the light polarized in a certain
direction appear slightly split. The mechanism causing such a behaviour in the
circularly polarized light is currently unknown. Trying to settle the issue of
short-term variability, we searched for changes in the spectral line profiles
on a time scale of 8-10min using HARPS polarimetric spectra and on a time scale
of 3-4min using time series obtained with the CORALIE spectrograph. No
significant variability was detected on these time scales during the epochs
studied.


  We investigated the characteristics of the spin fluctuations mediated
superconductivity employing the Eliashberg formalism. The effective interaction
between electrons was modeled in terms of the spin susceptibility measured by
the inelastic neutron scattering experiments on single crystal La2-xSrxCuO4
superconductors. The diagonal self-energy and off-diagonal self-energy were
calculated by solving the coupled Eliashberg equation self-consistently for
chosen spin susceptibility and tight-binding dispersion of electrons. The full
momentum and frequency dependence of the self-energy is presented for the
optimal, overdoped, and underdoped LSCO cuprates in superconductive state.
These results may be compared with the experimentally deduced self-energy from
ARPES experiments.


  Freezing interface interacting with soft cells is a core issue in
cryopreservation. However, most of existing cryopreservation approaches face
challenges such as complex processing and poor controllability. Herein we
report a new, nanotechnology-based method to modulate interfacial interactions
between ice and cells via the premelting theory. Through the interfacial design
by controllably modifying biocompatible nanoshells on the surface of cells, the
effective Hamaker constant between cells and ice can be modified. The thickness
of premelted films between cells and ice is further regulated, and directional
migration of coated cells occurs in a thermal gradient to achieve directional
thawing of coated cells. The decreased mortality of freezing coated cells
suggests the premelting modulation in freezing and thawing can effectively
protect cells from mechanical damage of ice formation during freezing and ice
recrystallization during thawing.


  To enhance image compression performance, recent deep neural network-based
research can be divided into three categories: a learnable codec, a
postprocessing network, and a compact representation network. The learnable
codec has been designed for an end-to-end learning beyond the conventional
compression modules. The postprocessing network increases the quality of
decoded images using an example-based learning. The compact representation
network is learned to reduce the capacity of an input image to reduce the
bitrate while keeping the quality of the decoded image. However, these
approaches are not compatible with the existing codecs or not optimal to
increase the coding efficiency. Specifically, it is difficult to achieve
optimal learning in the previous studies using the compact representation
network, due to the inaccurate consideration of the codecs. In this paper, we
propose a novel standard compatible image compression framework based on
Auxiliary Codec Networks (ACNs). ACNs are designed to imitate image degradation
operations of the existing codec, which delivers more accurate gradients to the
compact representation network. Therefore, the compact representation and the
postprocessing networks can be learned effectively and optimally. We
demonstrate that our proposed framework based on JPEG and High Efficiency Video
Coding (HEVC) standard substantially outperforms existing image compression
algorithms in a standard compatible manner.


  We study the equivariant cohomology of a class of multi-field topological LG
models, and find that such systems carry intrinsic information about
$W$-gravity. As a result, we can construct the gravitational chiral ring in
terms of LG polynomials. We find, in particular, that the spectrum of such
theories seems to be richer than so far expected. We also briefly discuss the
BRST operator for non-linear topological $W$-gravity.


  Connections between the second Chow group of a smooth projective variety and
its third unramified cohomology group, with coefficients the roots of unity
twisted twice, feature in several recent works. In this note we revisit a 1996
paper by B. Kahn and specialize it to various types of rationally connected
varieties.


  Using the well-known recognition and structural theorem(s) for root-graded
Lie algebras and their universal coverings, we give a finite presentation for
the universal covering algebra of a centerless Lie torus of type
$X\not=A,C,BC$. We follow a unified approach for the types under consideration.


  Equations of motion for an electrically charged string with a current in an
external electromagnetic field with regard to the first correction due to the
self-action are derived. It is shown that the reparametrization invariance of
the free action of the string imposes constraints on the possible form of the
current. The effective equations of motion are obtained for an absolutely
elastic charged string in the form of a ring (circle). Equations for the
external electromagnetic fields that admit stationary states of such a ring are
revealed. Solutions to the effective equations of motion of an absolutely
elastic charged ring in the absence of external fields as well as in an
external uniform magnetic field are obtained. In the latter case, the frequency
at which one can observe radiation emitted by the ring is evaluated. A model of
an absolutely nonstretchable charged string with a current is proposed. The
effective equations of motion are derived within this model, and a class of
solutions to these equations is found.


  Carrier graphs were first introduced for closed hyperbolic 3-manifolds by
White. In this paper, we first generalize this definition to carrier graphs for
representations of a rank two free group into the isometry group of hyperbolic
three space. Then we prove the existence and the finiteness of minimal carrier
graphs for those representations which are discrete, faithful and geometrically
finite, and more generally, those that satisfy certain finiteness conditions
first introduced by Bowditch.


  A symmetry classification is performed for a class of differential-difference
equations depending on 9 parameters. A 6-parameter subclass of these equations
is an integrable discretization of the Krichever-Novikov equation. The
dimension $n$ of the Lie point symmetry algebra satisfies $1 \le n \le 5$. The
highest dimensions, namely $n=5$ and $n=4$ occur only in the integrable cases.


  We analysed 30 RR Lyrae stars (RRLs) located in the Large Magellanic Cloud
(LMC) globular cluster Reticulum that were observed in the 3.6 and 4.5 $\mu$m
passbands with the Infrared Array Camera (IRAC) on board of the Spitzer Space
Telescope. We derived new mid-infrared (MIR) period-luminosity PL relations.
The zero points of the PL relations were estimated using the trigonometric
parallaxes of five bright Milky Way (MW) RRLs measured with the Hubble Space
Telescope (HST) and, as an alternative, we used the trigonometric parallaxes
published in the first Gaia data release (DR1) which were obtained as part of
the Tycho-Gaia Astrometric Solution (TGAS) and the parallaxes of the same stars
released with the second Gaia data release (DR2). We determined the distance to
Reticulum using our new MIR PL relations and found that distances calibrated on
the TGAS and DR2 parallaxes are in a good agreement and, generally, smaller
than distances based on the HST parallaxes, although they are still consistent
within the respective errors. We conclude that Reticulum is located ~3 kpc
closer to us than the barycentre of the LMC.


  Cell spreading and motility on an adhesive substrate are driven by the active
physical forces generated by the actin cytoskeleton. We have recently shown
that coupling curved membrane complexes to protrusive forces, exerted by the
actin polymerization that they recruit, provides a mechanism that can give rise
to spontaneous membrane shapes and patterns. In the presence of an adhesive
substrate, this model was shown to give rise to an emergent motile phenotype,
resembling a motile cell. Here, we utilize this ``minimal-cell" model to
explore the impact of external shear flow on the cell shape and migration on a
uniform adhesive flat substrate. We find that in the presence of shear the
motile cell reorients such that its leading edge, where the curved active
proteins aggregate, faces the shear flow. The flow-facing configuration is
found to minimize the adhesion energy by allowing the cell to spread more
efficiently over the substrate. For the non-motile vesicle shapes, we find that
they mostly slide and roll with the shear flow. We compare these theoretical
results with experimental observations, and suggest that the tendency of many
cell types to move against the flow may arise from the very general, and
non-cell-type-specific mechanism predicted by our model.


  The task of motion forecasting is critical for self-driving vehicles (SDVs)
to be able to plan a safe maneuver. Towards this goal, modern approaches reason
about the map, the agents' past trajectories and their interactions in order to
produce accurate forecasts. The predominant approach has been to encode the map
and other agents in the reference frame of each target agent. However, this
approach is computationally expensive for multi-agent prediction as inference
needs to be run for each agent. To tackle the scaling challenge, the solution
thus far has been to encode all agents and the map in a shared coordinate frame
(e.g., the SDV frame). However, this is sample inefficient and vulnerable to
domain shift (e.g., when the SDV visits uncommon states). In contrast, in this
paper, we propose an efficient shared encoding for all agents and the map
without sacrificing accuracy or generalization. Towards this goal, we leverage
pair-wise relative positional encodings to represent geometric relationships
between the agents and the map elements in a heterogeneous spatial graph. This
parameterization allows us to be invariant to scene viewpoint, and save online
computation by re-using map embeddings computed offline. Our decoder is also
viewpoint agnostic, predicting agent goals on the lane graph to enable diverse
and context-aware multimodal prediction. We demonstrate the effectiveness of
our approach on the urban Argoverse 2 benchmark as well as a novel highway
dataset.


  An artin algebra $A$ is said to be CM-finite if there are only finitely many,
up to isomorphisms, indecomposable finitely generated Gorenstein-projective
$A$-modules. We prove that for a Gorenstein artin algebra, it is CM-finite if
and only if every its Gorenstein-projective module is a direct sum of finitely
generated Gorenstein-projective modules. This is an analogue of Auslander's
theorem on algebras of finite representation type (\cite{A,A1}).


  A hyperelliptic curve over $\mathbb Q$ is called "locally soluble" if it has
a point over every completion of $\mathbb Q$. In this paper, we prove that a
positive proportion of hyperelliptic curves over $\mathbb Q$ of genus $g\geq 1$
are locally soluble but have no points over any odd degree extension of
$\mathbb Q$. We also obtain a number of related results. For example, we prove
that for any fixed odd integer $k > 0$, the proportion of locally soluble
hyperelliptic curves over $\mathbb Q$ of genus $g$ having no points over any
odd degree extension of $\mathbb Q$ of degree at most $k$ tends to 1 as $g$
tends to infinity. We also show that the failures of the Hasse principle in
these cases are explained by the Brauer-Manin obstruction. Our methods involve
a detailed study of the geometry of pencils of quadrics over a general field of
characteristic not equal to 2, together with suitable arguments from the
geometry of numbers.


  Gender information is no longer a mandatory input when registering for an
account at many leading Internet companies. However, prediction of demographic
information such as gender and age remains an important task, especially in
intervention of unintentional gender/age bias in recommender systems. Therefore
it is necessary to infer the gender of those users who did not to provide this
information during registration. We consider the problem of predicting the
gender of registered users based on their declared name. By analyzing the first
names of 100M+ users, we found that genders can be very effectively classified
using the composition of the name strings. We propose a number of character
based machine learning models, and demonstrate that our models are able to
infer the gender of users with much higher accuracy than baseline models.
Moreover, we show that using the last names in addition to the first names
improves classification performance further.


  Some models of leptogenesis involve a quasi-degenerate pair of heavy
neutrinos $N_{1,2}$ whose masses can be small, $O({\rm GeV})$. Such neutrinos
can contribute to the rare lepton-number-violating (LNV) decay $W^\pm \to
\ell_1^\pm \ell_2^\pm (q'{\bar q})^\mp$. If both $N_1$ and $N_2$ contribute,
there can be a CP-violating rate difference between the LNV decay of a $W^-$
and its CP-conjugate decay. In this paper, we examine the prospects for
measuring such a CP asymmetry $A_{\rm CP}$ at the LHC. We assume a value for
the heavy-light neutrino mixing parameter $|B_{\ell N}|^2 = 10^{-5}$, which is
allowed by the present experimental constraints, and consider $5~{\rm GeV} \le
M_N \le 80~{\rm GeV}$. We consider three versions of the LHC -- HL-LHC, HE-LHC,
FCC-hh -- and show that small values of the CP asymmetry can be measured at
$3\sigma$, in the range $1\% \lesssim A_{\rm CP} \lesssim 15\%$.


  We consider degenerate diffusion equations of the form $\partial_tp_t =
\Delta f(p_t)$ on a bounded domain and subject to no-flux boundary conditions,
for a class of nonlinearities $f$ that includes the porous medium equation. We
derive for them a trajectorial analogue of the entropy dissipation identity,
which describes the rate of entropy dissipation along every path of the
diffusion. Our approach is based on applying stochastic calculus to the
underlying probabilistic representations, which in our context are stochastic
differential equations with normal reflection on the boundary. This
trajectorial approach also leads to a new derivation of the Wasserstein
gradient flow property for nonlinear diffusions, as well as to a simple proof
of the HWI inequality in the present context.


  We conjecture that if $G$ is a finite primitive group and if $g$ is an
element of $G$, then either the element $g$ has a cycle of length equal to its
order, or for some $r,m$ and $k$, the group $G\leq S_m\wr S_r$, preserving a
product structure of $r$ direct copies of the natural action of $S_m$ or $A_m$
on $k$-sets. In this paper we reduce this conjecture to the case that $G$ is an
almost simple group with socle a classical group.


  We review exact solutions of black holes in higher dimensions, focusing on
asymptotically flat black hole solutions and Kaluza-Klein type black hole
solutions. We also summarize some properties which such black hole solutions
reveal.


  A search for W' bosons decaying to a top and a bottom quark in final states
including an electron or a muon is performed with the CMS detector at the LHC.
The analyzed data correspond to an integrated luminosity of 138 fb$^{-1}$ of
proton-proton collisions at a center-of-mass energy of 13 Tev. Good agreement
with the standard model expectation is observed and no evidence for the
existence of the W' boson is found over the mass range examined. The largest
observed deviation from the standard model expectation is found for a W' boson
mass ($m_\mathrm{W'}$) hypothesis of 3.8 TeV with a relative decay width of 1%,
with a local (global) significance of 2.6 (2.0) standard deviations. Upper
limits on the production cross sections of W' bosons decaying to a top and a
bottom quark are set. Left- and right-handed W' bosons with $m_\mathrm{W'}$
below 3.9 and 4.3 TeV, respectively, are excluded at the 95% confidence level,
under the assumption that the new particle has a narrow decay width. Limits are
also set for relative decay widths up to 30%.


  We prove a generalization of the strong subadditivity of the von Neumann
entropy for bosonic quantum Gaussian systems. Such generalization determines
the minimum values of linear combinations of the entropies of subsystems
associated to arbitrary linear functions of the quadratures, and holds for
arbitrary quantum states including the scenario where the entropies are
conditioned on a memory quantum system. We apply our result to prove new
entropic uncertainty relations with quantum memory, a generalization of the
quantum Entropy Power Inequality, and the linear time scaling of the
entanglement entropy produced by quadratic Hamiltonians.


  High refractive index dielectric nanoparticles have provided a new platform
for exotic light manipulation through the interference of multipole modes. The
Kerker effect is one example of a Huygens source design. Rather than exploiting
interference between the electric dipole and magnetic dipole, as in many
conventional Huygens source designs, we explore Kerker-type suppressed backward
scattering mediated by the dominant electric dipole, toroidal dipole and
magnetic quadrupole. These modes are provided by a designed and fabricated CMOS
compatible ultra-thin Silicon nanodisk metasurface with a suppressed magnetic
dipole contribution, and verified through multipole decomposition. The
non-trivial substrate effect is considered using a semi-analytical transfer
matrix model. The model successfully predicts the observed reflection dip. By
applying a general criterion for constructive and destructive interference, it
is shown that while constructive interference occurs between the electric and
toroidal dipole contributions, the experimentally observed suppressed backward
Kerker-type scattering arises from the destructive interference between
backward scattered contributions due to the total electric dipole and the
magnetic quadrupole. Our study paves the way towards new types of Huygens
sources or metasurface design, such as for peculiar transverse Kerker
scattering.


  The Sun provides a standard reference against which we compare the chemical
abundances found anywhere else in the Universe. Nevertheless, there is not a
unique 'solar' composition, since the chemical abundances found in the solar
interior, the photosphere, the upper atmosphere, or the solar wind, are not
exactly the same. The composition of the solar photosphere, usually preferred
as a reference, changes with time due to diffusion, convection, and probably
accretion. In addition, we do not know the solar photospheric abundances,
inferred from the analysis of the solar spectrum using model atmospheres, with
high accuracy, and uncertainties for many elements exceed 25%. This paper gives
an overview of the methods and pitfalls of spectroscopic analysis, and
discusses the chemistry of the Sun in the context of the solar system.


  The latest advances in the field of photonics have enabled the simulation of
an increasing number of quantum models in photonic systems, turning them into
an important tool for realizing exotic quantum phenomena. In this paper we
suggest different ways in which these systems can be used to study the
interplay between flat band dynamics, topology and interactions in a well-known
quasi-1D topological insulator: the Creutz ladder. Firstly, a simple
experimental protocol is proposed to observe the Aharonov-Bohm localization in
the noninteracting system, and the different experimental setups that might be
used for this are reviewed. We then consider the inclusion of a repulsive
Hubbard-type interaction term, which can give rise to repulsively bound pairs
termed doublons. The dynamics of these quasiparticles are studied for different
points of the phase diagram, including a regime in which pairs are localized
and particles are free to move. Finally, a scheme for the photonic
implementation of a two-particle bosonic Creutz-Hubbard model is presented.


  The use of non-ideal features of semiconductor devices is an interesting
option for implementations of nonlinear electronic systems. This paper analyzes
the Chua circuit with nonlinearity based on the exponential hyperbolic
characteristics of semiconductor devices. The stability analysis using
describing functions predicts the dynamics of this nonlinear system, which is
corroborated by numerical investigations and experimental results. The dynamic
behaviors and bifurcations of this nonlinear system are mapped in parameter
space in order to create a base for studies, analyses, and designs. The dynamic
behavior of the experimental high speed implementation of this version of Chua
circuit differs from the expected dynamics for a conventional Chua circuit due
to effects of unmodelled non-idealities of the real semiconductor devices,
displaying that new and different dynamics for the Chua circuit can be obtained
exploring different nonlinearities.


  When studying the thermodynamic properties of mesoscopic systems the most
appropriate microcanonical entropy is the volume entropy, i.e. the logarithm of
the volume of phase space enclosed by the hypersurface of constant energy. For
systems with broken ergodicity, the volume entropy has discontinuous jumps at
values of energy that correspond to separatrix trajectories. Simultaneously
there is a convex intruder in the entropy function and a region of negative
specific heat below such critical energies. We illustrate this with a simple
model composed of a chain of 3 particles which interact via a Lennard-Jones
potential.


  The main concern of this study is to find the optimal design of truss
structures considering sizing and layout variables simultaneously. As compared
to purely sizing optimization problems, this problem is more challenging since
the two types of variables involved are fundamentally different in nature. In
this paper, a reinforcement learning method combining the update process and
Monte Carlo tree search called the update Monte Carlo tree search (UMCTS) for
sizing optimization problems is applied to solve combined sizing and layout
optimization for truss structures. This study proposes a novel update process
for nodal coordinates with two features. (1) The allowed range of each
coordinate varies in each round. (2) Accelerators for the number of entries in
the allowed range and iteration numbers are introduced to reduce the
computation time. Furthermore, nodal coordinates and member areas are
determined at the same time with only one search tree in each round. The
validation and efficiency of the UMCTS are tested on benchmark problems of
planar and spatial trusses with discrete sizing variables and continuous layout
variables. It is shown that the CPU time of the UMCTS is two times faster than
the branch and bound method. The numerical results demonstrate that the
proposed method stably achieves a better solution than other traditional
methods.


  Elastic periodic lattices act as mechanical filters of incident vibrations.
By and large, they forbid wave propagation within bandgaps and resonate outside
them. However, they often encounter "truncation resonances" (TRs) inside
bandgaps when certain conditions are met. In this study, we show that the
extent of unit cell asymmetry, its mass and stiffness contrasts, and the
boundary conditions all play a role in the TR location and wave profile. The
work is experimentally supported via two examples that validate the
methodology, and a set of design charts is provided as a blueprint for
selective TR placement in diatomic lattices.


  We study R-covered foliations of 3-manifolds from the point of view of their
transverse geometry. For an R-covered foliation in an atoroidal 3-manifold M,
we show that M-tilde can be partially compactified by a canonical cylinder
S^1_univ x R on which pi_1(M) acts by elements of Homeo(S^1) x Homeo(R), where
the S^1 factor is canonically identified with the circle at infinity of each
leaf of F-tilde. We construct a pair of very full genuine laminations
transverse to each other and to F, which bind every leaf of F. This pair of
laminations can be blown down to give a transverse regulating pseudo-Anosov
flow for F, analogous to Thurston's structure theorem for surface bundles over
a circle with pseudo-Anosov monodromy.
  A corollary of the existence of this structure is that the underlying
manifold M is homotopy rigid in the sense that a self-homeomorphism homotopic
to the identity is isotopic to the identity. Furthermore, the product
structures at infinity are rigid under deformations of the foliation F through
R-covered foliations, in the sense that the representations of pi_1(M) in
Homeo((S^1_univ)_t) are all conjugate for a family parameterized by t. Another
corollary is that the ambient manifold has word-hyperbolic fundamental group.
  Finally we speculate on connections between these results and a program to
prove the geometrization conjecture for tautly foliated 3-manifolds.


  Spin excitations were studied by absorption spectroscopy in CaBaCo4O7 which
is a type-I multiferroic compound with the largest magnetic-order induced
ferroelectric polarization ({\Delta}P=17mC/m2) reported, so far. We observed
two optical magnon branches: a solely electric dipole allowed one and a mixed
magnetoelectric resonance. The entangled magnetization and polarization
dynamics of the magnetoelectric resonance gives rise to unidirectional light
absorption, i.e. that magnon mode absorbs the electromagnetic radiation for one
propagation direction but not for the opposite direction. Our systematic study
of the magnetic field and temperature dependence of magnon modes provides
information about the energies and symmetries of spin excitations, which is
required to develop a microscopic spin model of CaBaCo4O7.


  Access libraries such as ROOT and HDF5 allow users to interact with datasets
using high level abstractions, like coordinate systems and associated slicing
operations. Unfortunately, the implementations of access libraries are based on
outdated assumptions about storage systems interfaces and are generally unable
to fully benefit from modern fast storage devices. The situation is getting
worse with rapidly evolving storage devices such as non-volatile memory and
ever larger datasets. This project explores distributed dataset mapping
infrastructures that can integrate and scale out existing access libraries
using Ceph's extensible object model, avoiding re-implementation or even
modifications of these access libraries as much as possible. These programmable
storage extensions coupled with our distributed dataset mapping techniques
enable: 1) access library operations to be offloaded to storage system servers,
2) the independent evolution of access libraries and storage systems and 3)
fully leveraging of the existing load balancing, elasticity, and failure
management of distributed storage systems like Ceph. They also create more
opportunities to conduct storage server-local optimizations specific to storage
servers. For example, storage servers might include local key/value stores
combined with chunk stores that require different optimizations than a local
file system. As storage servers evolve to support new storage devices like
non-volatile memory, these server-local optimizations can be implemented while
minimizing disruptions to applications. We will report progress on the means by
which distributed dataset mapping can be abstracted over particular access
libraries, including access libraries for ROOT data, and how we address some of
the challenges revolving around data partitioning and composability of access
operations.


  We give a realization of the stable L\'evy forest of a given size conditioned
by its mass from the path of the unconditioned forest. Then, we prove an
invariance principle for this conditioned forest by considering $k$ independent
Galton-Watson trees whose offspring distribution is in the domain of attraction
of any stable law conditioned on their total progeny to be equal to $n$. We
prove that when $n$ and $k$ tend towards $+\infty$, under suitable rescaling,
the associated coding random walk, the contour and height processes converge in
law on the Skorokhod space respectively towards the "first passage bridge" of a
stable L\'evy process with no negative jumps and its height process.


  3D hand shape and pose estimation from a single depth map is a new and
challenging computer vision problem with many applications. Existing methods
addressing it directly regress hand meshes via 2D convolutional neural
networks, which leads to artefacts due to perspective distortions in the
images. To address the limitations of the existing methods, we develop
HandVoxNet++, i.e., a voxel-based deep network with 3D and graph convolutions
trained in a fully supervised manner. The input to our network is a 3D
voxelized-depth-map-based on the truncated signed distance function (TSDF).
HandVoxNet++ relies on two hand shape representations. The first one is the 3D
voxelized grid of hand shape, which does not preserve the mesh topology and
which is the most accurate representation. The second representation is the
hand surface that preserves the mesh topology. We combine the advantages of
both representations by aligning the hand surface to the voxelized hand shape
either with a new neural Graph-Convolutions-based Mesh Registration
(GCN-MeshReg) or classical segment-wise Non-Rigid Gravitational Approach
(NRGA++) which does not rely on training data. In extensive evaluations on
three public benchmarks, i.e., SynHand5M, depth-based HANDS19 challenge and
HO-3D, the proposed HandVoxNet++ achieves state-of-the-art performance. In this
journal extension of our previous approach presented at CVPR 2020, we gain
41.09% and 13.7% higher shape alignment accuracy on SynHand5M and HANDS19
datasets, respectively. Our method is ranked first on the HANDS19 challenge
dataset (Task 1: Depth-Based 3D Hand Pose Estimation) at the moment of the
submission of our results to the portal in August 2020.


  We give a direct combinatorial proof of the equidistribution of two pairs of
permutation statistics, (des, aid) and (lec, inv), which have been previously
shown to have the same joint distribution as (exc, maj), the major index and
the number of excedances of a permutation. Moreover, the triple (pix, lec, inv)
was shown to have the same distribution as (fix, exc, maj), where fix is the
number of fixed points of a permutation. We define a new statistic aix so that
our bijection maps (pix, lec, inv) to (aix, des, aid). We also find an Eulerian
partner das for a Mahonian statistic mix defined using mesh patterns, so that
(das, mix) is equidistributed with (des, inv).


  The spectroscopic class of subdwarf A-type (sdA) stars has come into focus in
recent years because of their possible link to extremely low-mass white dwarfs,
a rare class of objects resulting from binary evolution. Although most sdA
stars are consistent with metal-poor halo main-sequence stars, the formation
and evolution of a fraction of these stars are still matters of debate. The
identification of photometric variability can help to put further constraints
on the evolutionary status of sdA stars, in particular through the analysis of
pulsations. Moreover, the binary ratio, which can be deduced from eclipsing
binaries and ellipsoidal variables, is important as input for stellar models.
In order to search for variability due to either binarity or pulsations in
objects of the spectroscopic sdA class, we have extracted all available high
precision light curves from the Kepler K2 mission. We have performed a thorough
time series analysis on all available light curves, employing three different
methods. Frequencies with a signal-to-noise ratio higher than four have been
used for further analysis. From the 25 targets, 13 turned out to be variables
of different kinds (i.e. classical pulsating stars, ellipsoidal and cataclysmic
variables, eclipsing binaries, and rotationally induced variables). For the
remaining 12 objects, a variability threshold was determined.


  We present the first semi-streaming algorithms to determine k-connectivity of
an undirected graph with k being any constant. The semi-streaming model for
graph algorithms was introduced by Muthukrishnan in 2003 and turns out to be
useful when dealing with massive graphs streamed in from an external storage
device.
  Our two semi-streaming algorithms each compute a sparse subgraph of an input
graph G and can use this subgraph in a postprocessing step to decide
k-connectivity of G. To this end the first algorithm reads the input stream
only once and uses time O(k^2*n) to process each input edge. The second
algorithm reads the input k+1 times and needs time O(k+alpha(n)) per input
edge. Using its constructed subgraph the second algorithm can also generate all
l-separators of the input graph for all l<k.


  Motivated by situations in which the removal of a zero (a.k.a., an absorbing
element) from a semigroup yields a subsemigroup with another zero, sets of
quasi-zeros (a.k.a., quasi-absorbing elements) are introduced as well as
primitive elements, minimal ideals and simple semigroups all with respect to a
given ideal. An application to set optimization is discussed.


  We study a spin-1/2-particle moving on a one dimensional lattice subject to
disorder induced by a random, space-dependent quantum coin. The discrete time
evolution is given by a family of random unitary quantum walk operators, where
the shift operation is assumed to be deterministic. Each coin is an independent
identically distributed random variable with values in the group of two
dimensional unitary matrices. We derive sufficient conditions on the
probability distribution of the coins such that the system exhibits dynamical
localization. Put differently, the tunneling probability between two lattice
sites decays rapidly for almost all choices of random coins and after arbitrary
many time steps with increasing distance. Our findings imply that this effect
takes place if the coin is chosen at random from the Haar measure, or some
measure continuous with respect to it, but also for a class of discrete
probability measures which support consists of two coins, one of them being the
Hadamard coin.


  The fastest quantum algorithms (for the solution of classical computational
tasks) known so far are basically variations of the hidden subgroup problem
with {$f(U[x])=f(x)$}. Following a discussion regarding which tasks might be
solved efficiently by quantum computers, it will be demonstrated by means of a
simple example, that the detection of more general hidden (two-point)
symmetries {$V\{f(x),f(U[x])\}=0$} by a quantum algorithm can also admit an
exponential speed-up. E.g., one member of this class of symmetries
{$V\{f(x),f(U[x])\}=0$} is discrete self-similarity (or discrete scale
invariance). PACS: 03.67.Lx, 89.70.+c.


  In Brodbeck et al 1999 it has been shown that the linearised time evolution
equations of general relativity can be extended to a system whose solutions
asymptotically approach solutions of the constraints. In this paper we extend
the non-linear equations in similar ways and investigate the effect of various
possibilities by numerical means. Although we were not able to make the
constraint submanifold an attractor for all solutions of the extended system,
we were able to significantly reduce the growth of the numerical violation of
the constraints. Contrary to our expectations this improvement did not imply a
numerical solution closer to the exact solution, and therefore did not improve
the quality of the numerical solution.


  The gas gain and energy resolution of single and double THGEM detectors
(5{\times}5cm2 effective area) with mini-rims (rim is less than 10{\mu}m) were
studied. The maximum gain can reach 5{\times}103 and 2{\times}105 for single
and double THGEM respectively, while the energy resolution of 5.9 keV X-ray
varied from 18% to 28% for both single and double THGEM detectors of different
hole sizes and thicknesses.All the experiments were investigated in mixture of
noble gases(argon,neon) and small content of other gases(iso-butane,methane) at
atmospheric pressure.


  The lunar Askaryan technique is a method to study the highest-energy cosmic
rays, and their predicted counterparts, the ultra-high-energy neutrinos. By
observing the Moon with a radio telescope, and searching for the characteristic
nanosecond-scale Askaryan pulses emitted when a high-energy particle interacts
in the outer layers of the Moon, the visible lunar surface can be used as a
detection area. Several previous experiments, at Parkes, Goldstone, Kalyazin,
Westerbork, the ATCA, Lovell, LOFAR, and the VLA, have developed the necessary
techniques to search for these pulses, but existing instruments have lacked the
necessary sensitivity to detect the known flux of cosmic rays from such a
distance. This will change with the advent of the SKA.
  The Square Kilometre Array (SKA) will be the world's most powerful radio
telescope. To be built in southern Africa, Australia and New Zealand during the
next decade, it will have an unsurpassed sensitivity over the key 100 MHz to
few-GHZ band. We introduce a planned experiment to use the SKA to observe the
highest-energy cosmic rays and, potentially, neutrinos. The estimated event
rate will be presented, along with the predicted energy and directional
resolution. Prospects for directional studies with phase 1 of the SKA will be
discussed, as will the major technical challenges to be overcome to make full
use of this powerful instrument. Finally, we show how phase 2 of the SKA could
provide a vast increase in the number of detected cosmic rays at the highest
energies, and thus to provide new insight into their spectrum and origin.


  After a brief overview of relevant studies on one-nucleon knockout showing
the importance of quantitatively understanding the origin of the quenched
spectroscopic factors extracted from data, attention is focussed on two-nucleon
emission as a suitable tool to investigate nucleon-nucleon correlations inside
complex nuclei. In particular, direct (e,e$'$pp) and (e,e$'$pn) reactions are
discussed, and the role of final-state interactions is studied. The influence
of the mutual interaction between the two outgoing nucleons is shown to depend
on the kinematics and on the type of the considered reaction.


  We proposed a new search heuristic using the scuba diving metaphor. This
approach is based on the concept of evolvability and tends to exploit
neutrality which exists in many real-world problems. Despite the fact that
natural evolution does not directly select for evolvability, the basic idea
behind the scuba search heuristic is to explicitly push evolvability to
increase. A comparative study of the scuba algorithm and standard local search
heuristics has shown the advantage and the limitation of the scuba search. In
order to tune neutrality, we use the NKq fitness landscapes and a family of
travelling salesman problems (TSP) where cities are randomly placed on a
lattice and where travel distance between cities is computed with the Manhattan
metric. In this last problem the amount of neutrality varies with the city
concentration on the grid ; assuming the concentration below one, this TSP
reasonably remains a NP-hard problem.


  The concept of entangled quantum states is considered in the context of
systems of identical particles, based on the requirement that in order to
represent physical states both for the overall system and the sub-systems which
may be entangled, the density operators must satisfy the symmetrisation
principle and global and local super-selection rules that prohibit states in
which there are coherences between differing particle numbers. These
requirements and their justification are fully discussed. In the second
quantisation approach used, both the system and the sub-systems are modes (or
sets of modes) rather than particles, particles being associated with different
occupancies of the modes. The definition of entangled states is based on first
defining the non-entangled states - after specifying which modes constitute the
sub-systems. This paper mainly focuses on two mode entanglement for massive
bosons. Several inequalities involving variances and mean values of operators
involving mode annihilation, creation operators have been proposed as tests for
two mode entangled states, including the inequalities that define spin
squeezing. Spin squeezing criteria in two mode systems are examined, and spin
squeezing is best considered for principle spin operator components where the
covariance matrix is diagonal. It is shown that the presence of spin squeezing
in at least one of the spin components requires entanglement of the relevant
pair of modes. Several of the other proposed tests for entanglement, including
ones based on the sum of the variances for two spin components are considered.
All of the tests are still valid when the present concept of entanglement based
on the symmetrisation and super-selection rule criteria is applied, but further
tests have been obtained here. Sometimes the new tests are satisfied whilst
than those obtained in other papers are not.


  We consider graphical games as introduced by Kearns et al. (2001). First we
analyse the interaction of graphicality with a notion of strategic equivalence
of games, providing a minimal complexity graphical description for games. Then
we study the interplay between graphicality and the classical decomposition of
games proposed by Candogan et al. (2011), characterizing the graphical
properties of each part of the decomposition.


  We prove spacetime weighted-L^2 estimates for the Schrodinger and wave
equation with an inverse-square potential. We then deduce Strichartz estimates
for these equations.


  The survey is devoted to the rationality question of finite linear groups. We
concentrate on lower-dimensional cases, especially on the case of dimension
four.


  Patient similarity assessment, which identifies patients similar to a given
patient, can help improve medical care. The assessment can be performed using
Electronic Medical Records (EMRs). Patient similarity measurement requires
converting heterogeneous EMRs into comparable formats to calculate their
distance. While versatile document representation learning methods have been
developed in recent years, it is still unclear how complex EMR data should be
processed to create the most useful patient representations. This study
presents a new data representation method for EMRs that takes the information
in clinical narratives into account. To address the limitations of previous
approaches in handling complex parts of EMR data, an unsupervised method is
proposed for building a patient representation, which integrates unstructured
data with structured data extracted from patients' EMRs. In order to model the
extracted data, we employed a tree structure that captures the temporal
relations of multiple medical events from EMR. We processed clinical notes to
extract symptoms, signs, and diseases using different tools such as medspaCy,
MetaMap, and scispaCy and mapped entities to the Unified Medical Language
System (UMLS). After creating a tree data structure, we utilized two novel
relabeling methods for the non-leaf nodes of the tree to capture two temporal
aspects of the extracted events. By traversing the tree, we generated a
sequence that could create an embedding vector for each patient. The
comprehensive evaluation of the proposed method for patient similarity and
mortality prediction tasks demonstrated that our proposed model leads to lower
mean squared error (MSE), higher precision, and normalized discounted
cumulative gain (NDCG) relative to baselines.


  Quantum neural networks (QNNs) succeed in object recognition, natural
language processing, and financial analysis. To maximize the accuracy of a QNN
on a Noisy Intermediate Scale Quantum (NISQ) computer, approximate synthesis
modifies the QNN circuit by reducing error-prone 2-qubit quantum gates. The
success of QNNs motivates adversaries to attack QNNs via backdoors. However,
na\"ively transplanting backdoors designed for classical neural networks to
QNNs yields only low attack success rate, due to the noises and approximate
synthesis on NISQ computers. Prior quantum circuit-based backdoors cannot
selectively attack some inputs or work with all types of encoding layers of a
QNN circuit. Moreover, it is easy to detect both transplanted and circuit-based
backdoors in a QNN.
  In this paper, we propose a novel and stealthy backdoor attack, QDoor, to
achieve high attack success rate in approximately-synthesized QNN circuits by
weaponizing unitary differences between uncompiled QNNs and their synthesized
counterparts. QDoor trains a QNN behaving normally for all inputs with and
without a trigger. However, after approximate synthesis, the QNN circuit always
predicts any inputs with a trigger to a predefined class while still acts
normally for benign inputs. Compared to prior backdoor attacks, QDoor improves
the attack success rate by $13\times$ and the clean data accuracy by $65\%$ on
average. Furthermore, prior backdoor detection techniques cannot find QDoor
attacks in uncompiled QNN circuits.


  Over the last decades, many prognostic models based on artificial
intelligence techniques have been used to provide detailed predictions in
healthcare. Unfortunately, the real-world observational data used to train and
validate these models are almost always affected by biases that can strongly
impact the outcomes validity: two examples are values missing not-at-random and
selection bias. Addressing them is a key element in achieving transportability
and in studying the causal relationships that are critical in clinical decision
making, going beyond simpler statistical approaches based on probabilistic
association.
  In this context, we propose a novel approach that combines selection
diagrams, missingness graphs, causal discovery and prior knowledge into a
single graphical model to estimate the cardiovascular risk of adolescent and
young females who survived breast cancer. We learn this model from data
comprising two different cohorts of patients. The resulting causal network
model is validated by expert clinicians in terms of risk assessment, accuracy
and explainability, and provides a prognostic model that outperforms competing
machine learning methods.


  We consider instanton effects in a non-supersymmetric gauge theory obtained
by marginal deformations of the N=4 SYM. This gauge theory is expected to be
dual to type IIB string theory on the AdS_5 times deformed-S^5 background. From
an instanton calculation in the deformed gauge theory we extract the prediction
for the dilaton-axion field \tau in dual string theory. In the limit of small
deformations where the supergravity regime is valid, our instanton result
reproduces the expression for \tau of the supergravity solution found by
Frolov.


  The properties of stable Luttinger liquid phases in models with a
non-conserved number of particles are investigated. We study the Luttinger
liquid phases in one-dimensional models of hard-core boson and spinless fermion
chains where particles can be created and annihilated three by three on
adjacent sites. We provide an intuitive and systematic method based on flow
equations approach, which accounts for additional terms in the correlations
generated by the $\mathbb{Z}_3$-symmetric interactions. We find that despite
the emergence of U(1) symmetry under renormalization, the observables are still
affected by its breaking in the bare Hamiltonian. In particular, the standard
bosonization mapping becomes insufficient to capture the full behavior of
correlation functions.


  We numerically solved the boundary-value problem for Tamm waves (which may
also be classified as Uller-Zenneck waves here) guided by the planar interface
of a homogeneous isotropic dissipative dielectric (HIDD) material and a
periodically multilayered isotropic dielectric material. The HIDD material was
chosen to be VO${}_2$ which, at optical wavelengths, has a
temperature-dependent refractive index with a hysteresis feature, i.e., the
temperature-dependence of its refractive index varies depending upon whether
the temperature is increasing or decreasing. A numerical code was implemented
to extract solutions of the dispersion equation at a fixed wavelength for both
$p$- and $s$-polarization states over the temperature range [50,80] degrees. A
multitude of Tamm waves of both linear polarization states were found,
demonstrating a clear demarcation of the heating and cooling phases in terms of
wavenumbers and propagation distances. Thereby, the signatures of thermal
hysteresis in Tamm-wave propagation were revealed.


  Many post-processing methods improve forecasts at individual locations but
remove their correlation structure, which is crucial for predicting
larger-scale events like total precipitation amount over areas such as river
catchments that are relevant for weather warnings and flood predictions. We
propose a method to reintroduce spatial correlation into a post-processed
forecast using an R-vine copula fitted to historical observations. This method
works similarly to related approaches like the Schaake shuffle and ensemble
copula coupling, i.e., by rearranging predictions at individual locations and
reintroducing spatial correlation while maintaining the post-processed marginal
distribution. Here, the copula measures how well an arrangement compares with
the historical distribution of precipitation. No close relationship is needed
between the post-processed marginal distributions and the spatial correlation
source. This is an advantage compared to Schaake shuffle and ensemble copula
coupling, which rely on a ranking with no ties at each considered location in
their source for spatial correlations. However, weather variables such as the
precipitation amount, whose distribution has an atom at zero, have rankings
with ties. To evaluate the proposed method, it is applied to a precipitation
forecast produced by a combination model with two input forecasts that deliver
calibrated marginal distributions but without spatial correlations. The
obtained results indicate that the calibration of the combination model carries
over to the output of the proposed model, i.e., the evaluation of area
predictions shows a similar improvement in forecast quality as the predictions
for individual locations. Additionally, the spatial correlation of the forecast
is evaluated with the help of object-based metrics, for which the proposed
model also shows an improvement compared to both input forecasts.


  A promising paradigm for offline reinforcement learning (RL) is to constrain
the learned policy to stay close to the dataset behaviors, known as policy
constraint offline RL. However, existing works heavily rely on the purity of
the data, exhibiting performance degradation or even catastrophic failure when
learning from contaminated datasets containing impure trajectories of diverse
levels. e.g., expert level, medium level, etc., while offline contaminated data
logs exist commonly in the real world. To mitigate this, we first introduce
gradient penalty over the learned value function to tackle the exploding
Q-functions. We then relax the closeness constraints towards non-optimal
actions with critic weighted constraint relaxation. Experimental results show
that the proposed techniques effectively tame the non-optimal trajectories for
policy constraint offline RL methods, evaluated on a set of contaminated D4RL
Mujoco and Adroit datasets.


  Astrotourism brings new opportunities to generate sustainable socio-economic
development, preserve cultural heritage, and inspire and educate the citizens
of the globe. This form of tourism can involve many different activities, such
as visiting observatories or travelling to remote areas to experience an
evening under a pristine, dark night sky. Together, our UK-Namibian
collaboration is working to develop and showcase astrotourism in Namibia, and
to enhance the possibility for astrotourism worldwide.


  Niobium nitride (NbN) is widely used in high-frequency superconducting
electronics circuits because it has one of the highest superconducting
transition temperatures ($T_c$ $\sim$ 16.5 K) and largest gap among
conventional superconductors. In its thin-film form, the $T_c$ of NbN is very
sensitive to growth conditions and it still remains a challenge to grow NbN
thin film (below 50 nm) with high $T_c$. Here, we report on the superconducting
properties of NbN thin films grown by high-temperature chemical vapor
deposition (HTCVD). Transport measurements reveal significantly lower disorder
than previously reported, characterized by a Ioffe-Regel ($k_F$$\ell$)
parameter of $\sim$ 14. Accordingly we observe $T_c$ $\sim$ 17.06 K (point of
50% of normal state resistance), the highest value reported so far for films of
thickness below 50 nm, indicating that HTCVD could be particularly useful for
growing high quality NbN thin films.


  In this paper, a parameterized deceleration parameter $q(z)= 1/2 - a/(1 +
z)^b$ is reconstructed from the latest type Ia supernovae gold dataset. It is
found out that the transition redshift from decelerated expansion to
accelerated expansion is at $z_T=0.35^{+0.14}_{-0.07}$ with $1\sigma$
confidence level in this parameterized deceleration parameter. And, the best
fit values of parameters in $1\sigma$ errors are $a=1.56^{+0.99}_{-0.55}$ and
$b=3.82^{+3.70}_{-2.27}$.


  The magneto-oscillations in graphene bilayers are studied in the vicinity of
the K and K' points of the Brillouin zone within the four-band continuum model
ased on the simplest tight-binding approximation involving only the nearest
neighbor interactions. The model is employed to construct Landau plots for a
variety of carrier concentrations and bias strengths between the graphene
planes. The quantum-mechanical and quasiclassical approaches are compared. We
found that the quantum magneto-oscillations are only asymptotically periodic
and reach the frequencies predicted quasiclassically for high indices of Landau
levels. In unbiased bilayers the phase of oscillations is equal to the phase of
massive fermions. Anomalous behavior of oscillation phases was found in biased
bilayers with broken inversion symmetry. The oscillation frequencies again tend
to quasiclassically predicted ones, which are the same for $K$ and $K'$, but
the quantum approach yields the gate-tunable corrections to oscillation phases,
which differ in sign for K and K'. These valley-dependent phase corrections
give rise, instead of a single quasiclassical series of oscillations, to two
series with the same frequency but shifted in phase.


  This article presents a survey of many nontrivial effects connected with the
coupling of electric and magnetic degrees of freedom in solids -- the field
initiated by I.~E.~Dzyaloshinskii in 1959. I briefly consider the main physics
of ultiferroic materials, and concentrate on different effects "beyond
multiferroics", based on the same physical mechanisms which operate in
multiferroics. In particular they lead to nontrivial electric properties of
different magnetic textures -- such as the appearance of dipoles on magnetic
monopoles in spin ice, dipoles on some domain walls in the usual ferromagnets,
on skyrmions etc. The inverse effect, the appearance of magnetic monopoles on
electric charges in magnetoelectrics, is also discussed. This nontrivial
electric activity of different magnetic textures has manifestations in many
experimental properties of these materials, and it can potentially lead to
novel applications.