  The chromospheric anemone microflares (AMF) are the transient solar phenomena
whose emission regions have a multi-ribbon configuration. As distinct from the
so-called "atypical" solar flares, also possessing a few ribbons, the temporal
and spatial scales of AMFs are a few times less, and the configuration of their
ribbons is more specific (star-like). The previously reported AMFs had
typically three or, less frequently, four ribbons; and it was shown in our
recent paper (Dumin and Somov: 2019, Astron. Astrophys. 623, L4) that they can
be reasonably described by the so-called GKSS model of magnetic field,
involving as few as four point-like magnetic sources with various polarity and
arrangement. To seek for the new types of AMFs, we performed inspection of the
large set of the emission patterns in the chromospheric line Ca II H recorded
by Hinode/SOT and confronted them with the respective magnetograms obtained by
SDO/HMI. As follows from this analysis, it is really possible to identify the
new unusual AMFs. Firstly, these are the flares occurring in the regions with
unbalanced magnetic flux. Secondly, and most interesting, it is possible to
identify the AMFs with much more complex spatial configurations, e.g.,
involving five luminous ribbons with a nontrivial arrangement. As follows from
the corresponding magnetograms, they are produced by the effective magnetic
sources (sunspots) of different polarity with intermittent arrangement, but
their number is greater than in the standard GKSS model.


  We introduce a simple and robust scheme for optical frequency transfer of an
ultra-stable source light field via an optical frequency comb to a field at a
target optical frequency, where highest stability is required, e.g. for the
interrogation of an optical clock. The scheme relies on a topology for
end-to-end suppression of the influence of optical path-length fluctuations,
which is attained by actively phase-stabilized delivery, combined with
common-path propagation. This approach provides a robust stability improvement
without the need for additional isolation against environmental disturbances
such as temperature, pressure or humidity changes. We measure residual
frequency transfer instabilities by comparing the frequency transfers carried
out with two independent combs simultaneously. Residual fractional frequency
instabilities between two systems of $8\times10^{-18}$ at 1 s and
$3\times10^{-21}$ at $10^5$ s averaging time are observed. We discuss the
individual noise contributions to the residual instability. The presented
scheme is technically simple, robust against environmental parameter
fluctuations, and enables an ultra-stable frequency transfer, e.g. to optical
clock lasers or to lasers in gravitational wave detectors.


  We report on small-amplitude optical variability and recent dissipation of
the unusually persistent broad emission lines in the blue compact dwarf galaxy
PHL 293B. The galaxy's unusual spectral features (P Cygni-like profiles with
$\sim$800 km s$^{-1}$ blueshifted absorption lines) have resulted in
conflicting interpretations of the nature of this source in the literature.
However, analysis of new Gemini spectroscopy reveals the broad emission has
begun to fade after being persistent for over a decade prior. Precise
difference imaging light curves constructed with the Sloan Digital Sky Survey
and the Dark Energy Survey reveal small-amplitude optical variability of
$\sim$0.1 mag in the g band offset by $100\pm21$ pc from the brightest pixel of
the host. The light curve is well-described by an active galactic nuclei
(AGN)-like damped random walk process. However, we conclude that the origin of
the optical variability and spectral features of PHL 293B is due to a
long-lived stellar transient, likely a Type IIn supernova or non-terminal
outburst, mimicking long-term AGN-like variability. This work highlights the
challenges of discriminating between scenarios in such extreme environments,
relevant to searches for AGNs in dwarf galaxies. This is the second long-lived
transient discovered in a blue compact dwarf, after SDSS1133. Our result
implies such long-lived stellar transients may be more common in
metal-deficient galaxies. Systematic searches for low-level variability in
dwarf galaxies will be possible with the upcoming Legacy Survey of Space and
Time at Vera C. Rubin Observatory.


  Low-temperature specific heat (SH) and resistivity were measured on
Ba(Fe_{1-x}Co_x)_2As_2 single crystals in wide doping region. A sizeable
residual specific heat coefficient \gamma_0 was observed in the low temperature
limit of all samples. The specific heat jump near T_c, i.e. \Delta C/T|_{T_c}
and the upper critical field H_{c2}^c (H||c) were also determined. It is found
that -\gamma_0, \Delta C/T|_{T_c}, \sqrt{H_{c2}^c} and T_c all shared a similar
evolution with doping. All these can be well understood within the model of
S$^\pm$ pairing symmetry when accounting the Co-dopants as unitary scattering
centers in the FeAs planes. Our results give a direct evidence for the
violation of the Anderson theorem in FeAs-based superconductors.


  In collaboration with Postpartum Support International (PSI), a non-profit
organization dedicated to supporting caregivers with postpartum mood and
anxiety disorders, we developed three chatbots to provide context-specific
empathetic support to postpartum caregivers, leveraging both rule-based and
generative models. We present and evaluate the performance of our chatbots
using both machine-based metrics and human-based questionnaires. Overall, our
rule-based model achieves the best performance, with outputs that are close to
ground truth reference and contain the highest levels of empathy. Human users
prefer the rule-based chatbot over the generative chatbot for its
context-specific and human-like replies. Our generative chatbot also produced
empathetic responses and was described by human users as engaging. However,
limitations in the training dataset often result in confusing or nonsensical
responses. We conclude by discussing practical benefits of rule-based vs.
generative models for supporting individuals with mental health challenges. In
light of the recent surge of ChatGPT and BARD, we also discuss the
possibilities and pitfalls of large language models for digital mental
healthcare.


  Many methodologies have been proposed to quickly identify among a very large
number of flight conditions and maneuvers (i.e., steady, quasi-steady and
unsteady loads cases) the ones which give the worst values for structural
sizing (e.g., bending moments, shear forces, torques,...). All of these methods
use both the simulation model of the aircraft under development and efficient
algorithms to find out the critical points of the flight envelope. At the
preliminary structural design phases detailed models are not available and
airframe's loads are estimated by empirical relationships or engineering
judgments. These approximations can induce load uncertainties and may lead to
expensive redesign activities through the upcoming detailed sizing process. In
the context of preliminary design phase for a weight aircraft variant without
geometric change, to overcome this likely drawback, we propose a method based
on the huge and reliable database of an initial aircraft from which the weight
variant belongs. More precisely, from the load cases of this initial database,
response surfaces are identified as functions of preliminary parameters (flight
conditions and structural parameters). Then, these response surfaces are used
to predict quickly the weight aircraft variant quantities of interest for
preliminary structural design studies. Although the proposed method can be
readily extended to any structural quantity of interest and to any flight
conditions and maneuvers, it is presented here for the prediction of the
bending moments due to discrete gust at different locations along a wing span.


  We use the numerical renormalization group theory to investigate the
Yu-Shiba-Rusinov (YSR) bound state properties of single magnetic molecules
placed in an s-wave superconducting substrate. The molecule consist of a large
core spin and a single orbital, coupled via an exchange interaction. The
critical Coulomb interaction for the singlet/doublet transition decreases in
the presence of this exchange interaction for both ferro and anti-ferromagnetic
couplings. The number of YSR states also increase to two pairs, however, in the
singlet phase, one of the pairs have zero spectral weight. We explore the
evolution of the in-gap states using the Anderson model. Away from the
particle-hole symmetry point, the results suggest a doublet-singlet-doublet
transition as the on-site energy is lowered while keeping the Coulomb
interaction fixed. To understand these results, we write down an effective
model for the molecule in the limit of large superconducting order parameter.
Qualitatively, it explains the various phase transitions and spectral nature of
the in-gap states. Finally, we analyze the effects of magnetic anisotropic
fields of the core spin on in-gap states. Due to internal degrees of freedom of
the spin excited states, a multitude of new states emerges within the gap.
Depending on the sign and strength of the uniaxial anisotropic field, the
results indicate up to three pairs of YSR states.


  We study two simple $CP$-violating asymmetries of leptons coming from the
decay of $t$ and $\o t$ in $e^+e^- \ra \tt$, which do not need the full
reconstruction of the $t$ or $\o t$ for their measurement. They can arise when
the top quark possesses nonzero electric and weak dipole form factors in the
couplings to the photon and $Z$, respectively. Together, these two asymmetries
can help to determine the electric and weak dipole form factors independently.
If longitudinal beam polarization is available, independent determination of
form factors can be done by measuring only one of the asymmetries. We obtain
estimates of 90\% confidence limits that can be put on these form factors at a
future linear $\ee$ collider operating at $\sqrt{s}=500$ GeV.


  Super-resolution imaging is vital for optical applications, such as high
capacity information transmission, real-time bio-molecular imaging and
nanolithography. Technology and method of super-resolution imaging have
attracted much attention. In recent years, different kinds of novel lens, from
the superlens to the super-oscillatory lens, has been designed and fabricated
to break out the diffraction limit. However, the effect of the super-resolution
imaging in these lenses is not satisfactory due to intrinsic loss, aberration,
bigger sidebands and single super-resolution imaging. In this research, we
introduce the solid immersion mechanism to Mikaelian lens (ML) for multiple
super-resolution imaging.


  In this paper, we study the Erd\H{o}s-Falconer distance problem in five
dimensions for sets of Cartesian product structures. More precisely, we show
that for $A\subset \mathbb{F}_p$ with $|A|\gg p^{\frac{13}{22}}$, then
$\Delta(A^5)=\mathbb{F}_p$. When $|A-A|\sim |A|$, we obtain stronger statements
as follows:
  If $|A|\gg p^{\frac{13}{22}}$, then $(A-A)^2+A^2+A^2+A^2+A^2=\mathbb{F}_p.$
  If $|A|\gg p^{\frac{4}{7}}$, then
$(A-A)^2+(A-A)^2+A^2+A^2+A^2+A^2=\mathbb{F}_p.$
  We also prove that if $p^{4/7}\ll |A-A|=K|A|\le p^{5/8}$, then \[|A^2+A^2|\gg
\min \left\lbrace \frac{p}{K^4},
\frac{|A|^{8/3}}{K^{7/3}p^{2/3}}\right\rbrace.\] As a consequence,
$|A^2+A^2|\gg p$ when $|A|\gg p^{5/8}$ and $K\sim 1$, where $A^2=\{x^2\colon
x\in A\}$.


  We address the design of opportunistic spectrum access (OSA) strategies that
allow secondary users to independently search for and exploit instantaneous
spectrum availability. Integrated in the joint design are three basic
components: a spectrum sensor that identifies spectrum opportunities, a sensing
strategy that determines which channels in the spectrum to sense, and an access
strategy that decides whether to access based on imperfect sensing outcomes.
  We formulate the joint PHY-MAC design of OSA as a constrained partially
observable Markov decision process (POMDP). Constrained POMDPs generally
require randomized policies to achieve optimality, which are often intractable.
By exploiting the rich structure of the underlying problem, we establish a
separation principle for the joint design of OSA. This separation principle
reveals the optimality of myopic policies for the design of the spectrum sensor
and the access strategy, leading to closed-form optimal solutions. Furthermore,
decoupling the design of the sensing strategy from that of the spectrum sensor
and the access strategy, the separation principle reduces the constrained POMDP
to an unconstrained one, which admits deterministic optimal policies. Numerical
examples are provided to study the design tradeoffs, the interaction between
the spectrum sensor and the sensing and access strategies, and the robustness
of the ensuing design to model mismatch.


  We investigate semi-stiff interacting self-avoiding walks on the square
lattice with random impurities. The walks are simulated using the flatPERM
algorithm and the inhomogeneity is realised as a random fraction of the lattice
that is unavailable to the walks. We calculate several thermodynamic and metric
quantities to map out the phase diagram and look at how the amount of disorder
affects the properties of each phase. On a homogeneous lattice this model has
an extended phase and two distinct collapsed phases, globular and crystalline,
which differ in the anisotropy of the walks. By adding impurities to the
lattice we notice a degree of swelling of the walks for all phases that is
commensurate with the fraction of the lattice that is removed. Importantly, the
crystal phase disappears with the addition of impurities for sufficiently long
walks. For finite length walks we demonstrate that competition between the size
of the average spaces free of impurities and the size of the collapsed polymer
describes the crossover between the homogeneous lattice and the impurity
dominated situation.


  We demonstrate the equivalence of the light-front and equal-time formulations
of pionic corrections to nucleon properties. As a specific example, we consider
the self-energy of a nucleon dressed by pion loops, for both pseudovector and
pseudoscalar pion-nucleon couplings. We derive the leading and next-to-leading
nonanalytic behavior of the self-energy on the light-front, and show explicitly
their equivalence in the rest frame and infinite momentum frame in equal-time
quantization, as well as in a manifestly covariant formulation.


  In this paper we verify that with the exception of the $(2, 2n+1)$ torus
knots, positive 2-bridge knots up to 31 crossings do not admit chirally
cosmetic surgeries. A knot $K$ admits chirally cosmetic surgeries if there
exist surgeries $S^3_r$ and $S^3_{r'}$ with distinct slopes $r$ and $r'$ such
that $S^3_r(K) \cong -S^3_{r'}(K)$, where the negative represents an
orientation reversal. To verify this, we use the obstruction formula from
arXiv:2112.03144 which relates classical knot invariants to the existence of
chirally cosmetic surgeries. To check the formula, we develop a Python program
that computes the classical knot invariants $a_2$, $a_4$, $v_3$, $\det$, and
$g$ of a positive 2-bridge knot.


  Real-time feedback-driven single-particle tracking is a technique that uses
feedback control to enable single-molecule spectroscopy of freely diffusing
particles in native or near-native environments. A number of different
RT-FD-SPT approaches exist, and comparisons between methods based on
experimental results are of limited use due to differences in samples and
setups. In this study, we used statistical calculations and dynamical
simulations to directly compare the performance of different methods. The
methods considered were the orbital method, the Knight`s Tour (grid scan)
method and MINFLUX, and we considered both fluorescence-based and
interferometric scattering (iSCAT) approaches. There is a fundamental trade-off
between precision and speed, with the Knight`s Tour method being able to track
the fastest diffusion but with low precision, and MINFLUX being the most
precise but only tracking slow diffusion. To compare iSCAT and fluorescence,
different biological samples were considered, including labeled and
intrinsically fluorescent samples. The success of iSCAT as compared to
fluorescence is strongly dependent on the particle size and the density and
photophysical properties of the fluorescent particles. Using a wavelength for
iSCAT that is negligibly absorbed by the tracked particle allows an increased
illumination intensity, which results in iSCAT providing better tracking for
most samples. This work highlights the fundamental aspects of performance in
RT-FD-SPT and should assist with the selection of an appropriate method for a
particular application. The approach used can easily be extended to other
RT-FD-SPT methods.


  An edge-weighted graph $G=(V,E)$ is called stable if the value of a
maximum-weight matching equals the value of a maximum-weight fractional
matching. Stable graphs play an important role in some interesting game theory
problems, such as network bargaining games and cooperative matching games,
because they characterize instances which admit stable outcomes. Motivated by
this, in the last few years many researchers have investigated the algorithmic
problem of turning a given graph into a stable one, via edge- and
vertex-removal operations. However, all the algorithmic results developed in
the literature so far only hold for unweighted instances, i.e., assuming unit
weights on the edges of $G$.
  We give the first polynomial-time algorithm to find a minimum cardinality
subset of vertices whose removal from $G$ yields a stable graph, for any
weighted graph $G$. The algorithm is combinatorial and exploits new structural
properties of basic fractional matchings, which are of independent interest. In
particular, one of the main ingredients of our result is the development of a
polynomial-time algorithm to compute a basic maximum-weight fractional matching
with minimum number of odd cycles in its support. This generalizes a
fundamental and classical result on unweighted matchings given by Balas more
than 30 years ago, which we expect to prove useful beyond this particular
application.
  In contrast, we show that the problem of finding a minimum cardinality subset
of edges whose removal from a weighted graph $G$ yields a stable graph, does
not admit any constant-factor approximation algorithm, unless $P=NP$. In this
setting, we develop an $O(\Delta)$-approximation algorithm for the problem,
where $\Delta$ is the maximum degree of a node in $G$.


  Machine learning has the potential to revolutionize passive acoustic
monitoring (PAM) for ecological assessments. However, high annotation and
compute costs limit the field's efficacy. Generalizable pretrained networks can
overcome these costs, but high-quality pretraining requires vast annotated
libraries, limiting its current applicability primarily to bird taxa. Here, we
identify the optimum pretraining strategy for a data-deficient domain using
coral reef bioacoustics. We assemble ReefSet, a large annotated library of reef
sounds, though modest compared to bird libraries at 2% of the sample count.
Through testing few-shot transfer learning performance, we observe that
pretraining on bird audio provides notably superior generalizability compared
to pretraining on ReefSet or unrelated audio alone. However, our key findings
show that cross-domain mixing which leverages bird, reef and unrelated audio
during pretraining maximizes reef generalizability. SurfPerch, our pretrained
network, provides a strong foundation for automated analysis of marine PAM data
with minimal annotation and compute costs.


  This paper reviews the field of gamma-ray astronomy and describes future
experiments and prospects for advances in fundamental physics and high-energy
astrophysics through gamma-ray measurements. We concentrate on recent progress
in the understanding of active galaxies, and the use of these sources as probes
of intergalactic space. We also describe prospects for future experiments in a
number of areas of fundamental physics, including: searches for an annihilation
line from neutralino dark matter, understanding the energetics of supermassive
black holes, using AGNs as cosmological probes of the primordial radiation
fields, constraints on quantum gravity, detection of a new spectral component
from GRBs, and the prospects for detecting primordial black holes.


  The critical behavior at a corner in two-dimensional Ising and three-state
Potts models is studied numerically on the square lattice using transfer
operator techniques. The local critical exponents for the magnetization and the
energy density for various opening angles are deduced from finite-size scaling
results at the critical point for isotropic or anisotropic couplings. The
scaling dimensions compare quite well with the values expected from conformal
invariance, provided the opening angle is replaced by an effective one in
anisotropic systems.


  We report the results of our CO J = 4 --> 3 line and rest frame 650 micron
continuum observations of the z=0.93 hyperluminous infrared galaxy FSC
15307+3252 using the Owens Valley Millimeter Array. No line or continuum
emission was detected, but the derived limits provide a useful constraint on
the temperature, emissivity, and mass of the cold dust associated with FSC
15307+3252 and its molecular gas content.
  The 3 sigma upper limit on the velocity integrated CO (4-3) line flux is 1.6
Jy km/s (for 300 km/s line width). This corresponds to a surprisingly small
total molecular gas mass limit of 5 x 10^9 h^{-2} solar mass for this galaxy
with infrared luminosity L(FIR) > 10^{13} solar luminosity. Combined with
existing photometry data, our 3 sigma upper limit of 5.1 mJy for the 239 GHz
(650 micron rest wavelength) continuum flux yields a total dust mass of 0.4-1.5
times 10^8 solar mass. The CO luminosity (thus molecular gas content) and the
resulting gas-to-dust ratio are lower than the values typical for the more
gas-rich infrared galaxies, but they are within the observed ranges. On the
other hand, FSC 15307+3252 has a dust content and infrared luminosity 40 and
200 times larger than the infrared bright elliptical-like galaxies NGC 1275 and
Cygnus A.
  The FIR luminosity to dust mass ratios, L(FIR)/M(dust), for all three
galaxies hosting a powerful AGN (FSC 10214+4724, FSC 15307+3252, Cygnus A) are
larger than reasonably expected for a galaxy dominated by a starburst and four
times larger than Arp 220. Therefore the bulk of the observe FIR luminosity in
these galaxies is likely powered by their luminous active nucleus.


  We use 50 (candidate) background X-ray sources (AGN) in the LMC field
observed in ROSAT PSPC observations to derive the observed log N - log S
relation. We correct for the varying PSPC exposure and the absorption due to
the galactic and the LMC gas. We compare the observed log N - log S with a
theoretical log N - log S of the soft extragalactic X-ray background (AGN and a
cluster of galaxy contribution). We find that the observed log N - log S has a
deficiency with respect to the theoretical log N - log S. Factors which can
account for such a deficiency are: (1) incompleteness of the selected AGN and
cluster of galaxies sample, (2) deviation of the log N - log S in the LMC field
from the log N - log S derived from a large sample of AGN in several fields,
(3) existence of gas additional to the HI represented in the Parkes HI map of
the LMC field. We investigate the likely contribution of these effects and find
that (1) a fraction of at most 30% of the background sources may not have been
found in this analysis and may contribute to the observed deficiency. (2) We
cannot exclude a deviation of the log N - log S in the field of the LMC from a
theoretical log N - log S, especially the cluster of galaxy contribution may
show variations across the sky. (3) If LMC gas (restricted to >10^21 cm^-2
columns) in addition to the HI represented in the Parkes map would be
responsible for the deficiency, then a factor of >0.3 (at 90% confidence) of
additional gas would be required. This would equal a molecular mass fraction of
>21%, which would be larger than, but within the uncertainties consistent with
a molecular mass fraction of ~30% derived from CO observations (for columns
>10^21 cm^-2).


  We consider a (generally, non-coercive) mixed boundary value problem in a
bounded domain $D$ of ${\mathbb R}^n$ for a second order parameter-dependent
elliptic differential operator $A (x,\partial, \lambda)$ with complex-valued
essentially bounded measured coefficients and complex parameter $\lambda$. The
differential operator is assumed to be of divergent form in $D$, the boundary
operator $B (x,\partial)$ is of Robin type with possible pseudo-differential
components on $\partial D$. The boundary of $D$ is assumed to be a Lipschitz
surface. Under these assumptions the pair $(A (x,\partial, \lambda),B)$ induces
a holomorphic family of Fredholm operators $L(\lambda): H^+(D) \to H^- (D)$ in
suitable Hilbert spaces $H^+(D)$ , $H^- (D)$ of Sobolev type. If the argument
of the complex-valued multiplier of the parame\-ter in $A (x,\partial,
\lambda)$ is continuous and the coefficients related to second order
derivatives of the operator are smooth then we prove that the operators
$L(\lambda)$ are conti\-nu\-ously invertible for all $\lambda$ with
sufficiently large modulus $|\lambda|$ on each ray on the complex plane
$\mathbb C$ where the differential operator $A (x,\partial, \lambda)$ is
parameter-dependent elliptic. We also describe reasonable conditions for the
system of root functions related to the family $L (\lambda)$ to be (doubly)
complete in the spaces $H^+(D)$, $H^- (D)$ and the Lebesgue space $L^2 (D)$.


  The nearby transiting planet HD 189733b was observed during three transits
with the ACS camera of the Hubble Space Telescope in spectroscopic mode. The
resulting time series of 675 spectra covers the 550-1050 nm range, with a
resolution element of ~8 nm, at extremely high accuracy (signal-to-noise ratio
up to 10,000 in 50 nm intervals in each individual spectrum). Using these data,
we disentangle the effects of limb darkening, measurement systematics, and
spots on the surface of the host star, to calculate the wavelength dependence
of the effective transit radius to an accuracy of ~50 km. This constitutes the
``transmission spectrum'' of the planetary atmosphere. It indicates at each
wavelength at what height the planetary atmosphere becomes opaque to the
grazing stellar light during the transit. In this wavelength range, strong
features due to sodium, potassium and water are predicted by atmosphere models
for a planet like HD 189733b, but they can be hidden by broad absorption from
clouds or hazes higher up in the atmosphere.
  We observed an almost featureless transmission spectrum between 550 and 1050
nm, with no indication of the expected sodium or potassium atomic absorption
features. Comparison of our results with the transit radius observed in the
near and mid-infrared (2-8 microns), and the slope of the spectrum, suggest the
presence of a haze of sub-micron particles in the upper atmosphere of the
planet.


  We introduce N-extended (p,q) AdS superspaces in three space-time dimensions,
with p+q=N and p>=q, and analyse their geometry. We show that all (p,q) AdS
superspaces with X^{IJKL}=0 are conformally flat. Nonlinear sigma-models with
(p,q) AdS supersymmetry exist for p+q<=4 (for N>4 the target space geometries
are highly restricted). Here we concentrate on studying off-shell N=3
supersymmetric sigma-models in AdS_3. For each of the cases (3,0) and (2,1), we
give three different realisations of the supersymmetric action. We show that
(3,0) AdS supersymmetry requires the sigma-model to be superconformal, and
hence the corresponding target space is a hyperkahler cone. In the case of
(2,1) AdS supersymmetry, the sigma-model target space must be a non-compact
hyperkahler manifold endowed with a Killing vector field which generates an
SO(2) group of rotations of the two-sphere of complex structures.


  In this paper, the notion of $\mathcal{W}$-property for subsets of $X\times
X^{\lozenge}$ is introduced and investigated, where $X$ is an Hadamard space
and $X^{\lozenge}$ is its linear dual space. It is shown that an Hadamard space
$X$ is flat if and only if $X\times X^{\lozenge}$ has $\mathcal{W}$-property.
Moreover, the notion of monotone relation from an Hadamard space to its linear
dual space is introduced. Finally, a characterization result for monotone
relations with $\mathcal{W}$-property (and hence in flat Hadamard spaces) is
proved.


  We present a measurement of the linear growth rate of structure, \textit{f}
from the Sloan Digital Sky Survey III (SDSS III) Baryon Oscillation
Spectroscopic Survey (BOSS) Data Release 12 (DR12) using Convolution Lagrangian
Perturbation Theory (CLPT) with Gaussian Streaming Redshift-Space Distortions
(GSRSD) to model the two point statistics of BOSS galaxies in DR12. The
BOSS-DR12 dataset includes 1,198,006 massive galaxies spread over the redshift
range $0.2 < z < 0.75$. These galaxy samples are categorized in three redshift
bins. Using CLPT-GSRSD in our analysis of the combined sample of the three
redshift bins, we report measurements of $f \sigma_8$ for the three redshift
bins. We find $f \sigma_8 = 0.430 \pm 0.054$ at $z_{\rm eff} = 0.38$, $f
\sigma_8 = 0.452 \pm 0.057$ at $z_{\rm eff} = 0.51$ and $f \sigma_8 = 0.457 \pm
0.052$ at $z_{\rm eff} = 0.61$. Our results are consistent with the predictions
of Planck $\Lambda$CDM-GR. Our constraints on the growth rates of structure in
the Universe at different redshifts serve as a useful probe, which can help
distinguish between a model of the Universe based on dark energy and models
based on modified theories of gravity. This paper is part of a set that
analyses the final galaxy clustering dataset from BOSS. The measurements and
likelihoods presented here are combined with others in Alam et al. 2016 to
produce the final cosmological constraints from BOSS.


  We present observations of the dusty emission from the young planetary
nebulae Hen2-113 and CPD-56 obtained with VLT/NACO, VLTI/MIDI. The central
stars of these two objects are Wolf-Rayet stars of the same spectral type
[WC10]. They share an impressive number of characteristics and are located at
similar distance, making the detection of any differences in their close
environment of great interest. Hen2-113 exhibits a clear ring-like structure of
about 0.4 arcsec in diameter, superimposed to a more diffuse environment
visible in L', M' and 8.7 micron bands. No clear core could be detected for
this object with MIDI through the N band. The dusty environment of CPD-568032
is much more compact, dominated by a bright, barely resolved, core whereas the
visible nebula exhibits an amazing complexity. From MIDI 8.7 micron acquisition
images (dominated by PAHs emission), the extension and geometry of the core
have been estimated and compared to the STIS/HST observations (De Marco et al.,
1997 and 2002). Moreover, high SNR fringes at low level have been detected with
projected baselines between 40 and 45 meters. This clear signal is interpreted
in terms of the bright inner rim of a dusty disk exposed to the flux from the
Wolf-Rayet star. The geometrical parameters of the N band flux distribution are
well constrained by means of simple geometrical models and a simple radiative
transfer model has been developed to extract the physical parameters of the
disk.


  The low frequency lattice vibrations and relaxations are investigated in
single crystals of the four 3D hybrid organolead perovskites, MAPbBr$_3$,
FAPbBr$_3$, MAPbI$_3$, and $\alpha$-FAPbI$_3$, at the Brillouin zone center
using Raman and Brillouin scattering and at the zone boundary using inelastic
neutron scattering. The temperature dependence of the PbX$_6$ lattice modes in
the four compounds can be renormalized into universal curves, highlighting a
common vibrational dynamics at the cubic to tetragonal transition. In
particular, no soft vibration is observed excluding a displacive-like
transitional dynamics. The reorientational (pseudospin) motions of the
molecular cations exhibit a seemingly order-disorder character recalling that
of plastic crystals, but attributed to a secondary order-parameter. At
ultra-low frequency, a quasi-elastic component evidenced by Brillouin
scattering and associated to the unresolved central peak observed in neutron
scattering, is attributed to center of mass anharmonic motions and rattling of
the molecular cations in the perovskite cavities. Its partially unexpressed
critical behavior at the transition points toward the general importance of
defects in HOPs preventing the net divergence of order parameter correlations
at the critical temperatures.


  Capture and tidal disruption of stars by the supermassive black hole in the
Galactic center (GC) should occur regularly. The energy released and dissipated
by this processes will affect both the ambient environment of the GC and the
Galactic halo. A single star of super-Eddington eruption generates a subsonic
out ow with an energy release of more than $10^{52}$ erg, which still is not
high enough to push shock heated gas into the halo. Only routine tidal
disruption of stars near the GC can provide enough cumulative energy to form
and maintain large scale structures like the Fermi Bubbles. The average rate of
disruption events is expected to be $10^{-4}$ ~ $10^{-5}$ yr$^{-1}$, providing
the average power of energy release from the GC into the halo of dW/dt ~
3*10$^{41}$ erg/s, which is needed to support the Fermi Bubbles. The GC black
hole is surrounded by molecular clouds in the disk, but their overall mass and
filling factor is too low to stall the shocks from tidal disruption events
significantly. The de facto continuous energy injection on timescales of Myr
will lead to the propagation of strong shocks in a density stratified Galactic
halo and thus create elongated bubble-like features, which are symmetric to the
Galactic midplane.


  A key design goal of erasure-coded clusters is to reduce the repair time. The
existing Erasure-coded data repair schemes are roughly classified into two
categories: 1. Designing rapid data repair (e.g., PPR) in a homogeneous
environment. 2. Constructing data repair (e.g., PPT) based on bandwidth in a
heterogeneous environment. However, these solutions are difficult to cope with
the heterogeneous and Rapidly-changing network in erasure-coded clusters. To
address this problem, a bandwidth-aware multi-level forwarding repair
algorithm, called BMFRepair, is proposed. BMFRepair monitors the network
bandwidth in real time when data is forwarded, and selects idle nodes with
high-bandwidth links to assist in forwarding. Thus, it can reduce the time
bottleneck caused by low link transmission. At the same time, multi-node repair
becomes very complicated when the bandwidth changes drastically. A multi-node
scheduling repairing algorithm, called MSRepair, is proposed for multi-node
repairing problems, which can repair multiple failed blocks in parallel by
scheduling node resources. The two algorithms can flexibly adapt to the rapidly
changing network environment and make full use of the bandwidth resources of
idle nodes. Most importantly, algorithms can continuously adjust the repair
plan according to the bandwidth change in fast and dynamic network. The
algorithms have been evaluated by both simulations on Mininet and real
experiments on Aliyun cloud platform ECS. Results show that compared with the
state-of-the-art repair schemes PPR and PPT, the algorithms can significantly
reduce the repair time in rapidly-changing network.


  The logarithmic sigma model describes the interactions between quarks via
sigma and pion exchanges. The effective mesonic potential is extended to the
finite temperature and it is numerically calculated using n-midpoint rule.
Meson properties such as the phase transition, the sigma and pion masses, and
the critical point temperature are examined as functions of temperature. The
obtained results are compared with other approaches. We conclude that the
calculated effective potential is successfully to predict the meson properties


  We consider systems of strict multivariate polynomial inequalities over the
reals. All polynomial coefficients are parameters ranging over the reals, where
for each coefficient we prescribe its sign. We are interested in the existence
of positive real solutions of our system for all choices of coefficients
subject to our sign conditions. We give a decision procedure for the existence
of such solutions. In the positive case our procedure yields a parametric
positive solution as a rational function in the coefficients. Our framework
allows to reformulate heuristic subtropical approaches for non-parametric
systems of polynomial inequalities that have been recently used in qualitative
biological network analysis and, independently, in satisfiability modulo theory
solving. We apply our results to characterize the incompleteness of those
methods.


  In this paper, we showed how a group acting regularly and a diagonal group
are embedded into the wreath products in there product action using the
Cartesian Decomposition.


  In this paper, we give some sufficient conditions for the infinite collisions
of independent simple random walks on a wedge comb with profile $\{f(n), n\in
\ZZ\}$. One interesting result is that if $f(n)$ has a growth order as $n\log
n$, then two independent simple random walks on the wedge comb will collide
infinitely many times. Another is that if $\{f(n); n\in \ZZ\}$ are given by
i.i.d. non-negative random variables with finite mean, then for almost all
wedge comb with such profile, three independent simple random walks on it will
collide infinitely many times.


  Particle and pairing densities in spherical even-even neutron-rich nuclei are
studied within the Skyrme-Hartree-Fock-Bogoliubov approach with the
density-dependent pairing interaction. The influence of the density dependence
of the pairing interaction on asymptotic properties of nucleonic distributions
are analyzed. It is demonstrated that the size of the neutron halo dramatically
depends on the behavior of the pairing interaction at low density.


  Speech enhancement (SE) aims to suppress the additive noise from a noisy
speech signal to improve the speech's perceptual quality and intelligibility.
However, the over-suppression phenomenon in the enhanced speech might degrade
the performance of downstream automatic speech recognition (ASR) task due to
the missing latent information. To alleviate such problem, we propose an
interactive feature fusion network (IFF-Net) for noise-robust speech
recognition to learn complementary information from the enhanced feature and
original noisy feature. Experimental results show that the proposed method
achieves absolute word error rate (WER) reduction of 4.1% over the best
baseline on RATS Channel-A corpus. Our further analysis indicates that the
proposed IFF-Net can complement some missing information in the over-suppressed
enhanced feature.


  The ubiquity of clouds in the atmospheres of exoplanets, especially of
super-Earths, is one of the outstanding issues for transmission spectra survey.
The understanding about the formation process of clouds in super-Earths is
necessary to interpret the observed spectra correctly. In this study, we
investigate the vertical distributions of particle size and mass density of
mineral clouds in super-Earths using a microphysical model that takes into
account the vertical transport and growth of cloud particles in a
self-consistent manner. We demonstrate that the vertical profiles of mineral
clouds significantly vary with the concentration of cloud condensation nuclei
and atmospheric metallicity. We find that the height of the cloud top increases
with increasing metallicity as long as the metallicity is lower than a
threshold. If the metallicity is larger than the threshold, the cloud-top
height no longer increases appreciably with metallicity because coalescence
yields larger particles of higher settling velocities. We apply our cloud model
to GJ1214 b and GJ436 b for which recent transmission observations suggest the
presence of high-altitude opaque clouds. For GJ436 b, we show that KCl
particles can ascend high enough to explain the observation. For GJ1214 b, by
contrast, the height of KCl clouds predicted from our model is too low to
explain its flat transmission spectrum. Clouds made of highly porous KCl
particles could explain the observations if the atmosphere is highly
metal-rich, and hence the particle microstructure might be a key to interpret
the flat spectrum of GJ1214 b.


  The infrared (IR) emission plays a crucial role for understanding the star
formation in galaxies hidden by dust. We first examined four estimators of the
IR luminosity of galaxies, L_fir (Helou et al. 1988), L_tir (Dale et al. 2001),
revised version of L_tir (Dale & Helou 2002) (we denote L_tir2), and L_ir
(Sanders & Mirabel 1996) by using the observed SEDs of well-known galaxies. We
found that L_ir provides excellent estimates of the total IR luminosity for a
variety of galaxy SEDs. The performance of L_tir2 was also found to be very
good. Using L_ir, we then statistically analyzed the IRAS PSCz galaxy sample
(Saunders et al. 2000) and found useful formulae relating the MIR monochromatic
luminosities [L(12um) and L(25um)], and L_ir. For this purpose we constructed a
subsample of 1420 galaxies with all IRAS four band (12, 25, 60, and 100um) flux
densities. We found linear relations between L_ir and MIR luminosities, L(12um)
and L(25um). The prediction error with 95-% confidence level is a factor of
4-5. Hence, these formulae are useful for the estimation of the total IR
luminosity only from 12um or 25um observations. We further tried to make an
`interpolation' formula for galaxies at 0<z<1. For this purpose we construct
the formula of the relation between 15-um luminosity and the total IR
luminosity. We conclude that the 15-um formula can be used as an estimator of
the total IR luminosity from 24um observation of galaxies at z \simeq 0.6.


  We consider a system in which an information source generates independent and
identically distributed status update packets from an observed phenomenon that
takes $n$ possible values based on a given pmf. These update packets are
encoded at the transmitter node to be sent to the receiver node. Instead of
encoding all $n$ possible realizations, the transmitter node only encodes the
most probable $k$ realizations and disregards whenever a realization from the
remaining $n-k$ values occurs. We find the average age and determine the
age-optimal real codeword lengths such that the average age at the receiver
node is minimized. Through numerical evaluations for arbitrary pmfs, we show
that this selective encoding policy results in a lower average age than
encoding every realization and find the age-optimal $k$. We also analyze a
randomized selective encoding policy in which the remaining $n-k$ realizations
are encoded and sent with a certain probability to further inform the receiver
at the expense of longer codewords for the selected $k$ realizations.


  We provide sufficient conditions on a Banach space $X$ in order that there
exist norm attaining operators of rank at least two from $X$ into any Banach
space of dimension at least two. For example, a rather weak such condition is
the existence of a non-trivial cone consisting of norm attaining functionals on
$X$. We go on to discuss density of norm attaining operators of finite rank
among all operators of finite rank, which holds for instance when there is a
dense linear subspace consisting of norm attaining functionals on $X$. In
particular, we consider the case of Hilbert space valued operators where we
obtain a complete characterization of these properties. In the final section we
offer a candidate for a counterexample to the complex Bishop-Phelps theorem on
$c_0$, the first such counterexample on a certain complex Banach space being
due to V. Lomonosov.


  Knot theory provides a powerful tool for the understanding of topological
matters in biology, chemistry, and physics. Here knot theory is introduced to
describe topological phases in the quantum spin system. Exactly solvable models
with long-range interactions are investigated, and Majorana modes of the
quantum spin system are mapped into different knots and links. The topological
properties of ground states of the spin system are visualized and characterized
using crossing and linking numbers, which capture the geometric topologies of
knots and links. The interactivity of energy bands is highlighted. In gapped
phases, eigenstate curves are tangled and braided around each other forming
links. In gapless phases, the tangled eigenstate curves may form knots. Our
findings provide an alternative understanding of the phases in the quantum spin
system, and provide insights into one-dimension topological phases of matter.


  We present six years of optical monitoring of the black hole candidate X-ray
binary Swift J1357.2-0933, during and since its discovery outburst in 2011. On
these long timescales, the quiescent light curve is dominated by high
amplitude, short term (seconds-days) variability spanning ~ 2 magnitudes, with
an increasing trend of the mean flux from 2012 to 2017 that is steeper than in
any other X-ray binary found to date (0.17 mag/yr). We detected the initial
optical rise of the 2017 outburst of Swift J1357.2-0933, and we report that the
outburst began between April 1 and 6, 2017. Such a steep optical flux rise
preceding an outburst is expected according to disk instability models, but the
high amplitude variability in quiescence is not. Previous studies have shown
that the quiescent spectral, polarimetric and rapid variability properties of
Swift J1357.2-0933 are consistent with synchrotron emission from a weak compact
jet. We find that a variable optical/infrared spectrum is responsible for the
brightening: a steep, red spectrum before and soon after the 2011 outburst
evolves to a brighter, flatter spectrum since 2013. The evolving spectrum
appears to be due to the jet spectral break shifting from the infrared in 2012
to the optical in 2013, then back to the infrared by 2016-2017 while the
optical remains relatively bright. Swift J1357.2-0933 is a valuable source to
study black hole jet physics at very low accretion rates, and is possibly the
only quiescent source in which the optical jet properties can be regularly
monitored.


  The aim of the paper is to extend the model of "fishing problem". The simple
formulation is following. The angler goes to fishing. He buys fishing ticket
for a fixed time. There are two places for fishing at the lake. The fishes are
caught according to renewal processes which are different at both places. The
fishes' weights and the inter-arrival times are given by the sequences of
i.i.d. random variables with known distribution functions. These distributions
are different for the first and second fishing place. The angler's satisfaction
measure is given by difference between the utility function dependent on size
of the caught fishes and the cost function connected with time. On each place
the angler has another utility functions and another cost functions. In this
way, the angler's relative opinion about these two places is modeled. For
example, on the one place better sort of fish can be caught with bigger
probability or one of the places is more comfortable. Obviously our angler
wants to have as much satisfaction as possible and additionally he have to
leave the lake before the fixed moment. Therefore his goal is to find two
optimal stopping times in order to maximize his satisfaction. The first time
corresponds to the moment, when he eventually should change the place and the
second time, when he should stop fishing. These stopping times have to be less
than the fixed time of fishing. The value of the problem and the optimal
stopping times are derived.


  Recently, there has been substantial interest in realizations of skyrmions,
in particular in 2D systems due to increased stability resulting from reduced
dimensionality. A stable skyrmion, representing the smallest realizable
magnetic texture, could be an ideal element for ultra-dense magnetic memories.
Here, we use the most general form of the 2D free energy with
Dzyaloshinskii-Moriya interactions constructed from general symmetry
considerations reflecting the underlying system. We predict that skyrmion phase
is robust and it is present even when the system lacks the in-plane rotational
symmetry. In fact, the lowered symmetry leads to increased stability of
vortex-antivortex lattices with four-fold symmetry and in-plane spirals, in
some instances even in the absence of an external magnetic field. Our results
relate different hexagonal and square cell phases to the symmetries of
materials used for realizations of skyrmions. This will give clear directions
for experimental realizations of hexagonal and square cell phases, and will
allow engineering of skyrmions with unusual properties. We also predict
striking differences in gyro-dynamics induced by spin currents for isolated
skyrmions and for crystals where spin currents can be induced by charge
carriers or by thermal magnons. We find that under certain conditions, isolated
skyrmions can move along the current without a side motion which can have
implications for realizations of magnetic memories.


  Sharding is the prevalent approach to breaking the trilemma of simultaneously
achieving decentralization, security, and scalability in traditional blockchain
systems, which are implemented as replicated state machines relying on atomic
broadcast for consensus on an immutable chain of valid transactions. Sharding
is to be understood broadly as techniques for dynamically partitioning nodes in
a blockchain system into subsets (shards) that perform storage, communication,
and computation tasks without fine-grained synchronization with each other.
Despite much recent research on sharding blockchains, much remains to be
explored in the design space of these systems. Towards that aim, we conduct a
systematic analysis of existing sharding blockchain systems and derive a
conceptual decomposition of their architecture into functional components and
the underlying assumptions about system models and attackers they are built on.
The functional components identified are node selection, epoch randomness, node
assignment, intra-shard consensus, cross-shard transaction processing, shard
reconfiguration, and motivation mechanism. We describe interfaces,
functionality, and properties of each component and show how they compose into
a sharding blockchain system. For each component, we systematically review
existing approaches, identify potential and open problems, and propose future
research directions. We focus on potential security attacks and performance
problems, including system throughput and latency concerns such as confirmation
delays. We believe our modular architectural decomposition and in-depth
analysis of each component, based on a comprehensive literature study, provides
a systematic basis for conceptualizing state-of-the-art sharding blockchain
systems, proving or improving security and performance properties of
components, and developing new sharding blockchain system designs.


  The full spectrum of two-dimensional fermion states in a scalar soliton trap
with a Lorentz breaking background is investigated in the context of the novel
2D materials, where the Lorentz symmetry should not be strictly valid. The
field theoretical model with Lorentz breaking terms represents Dirac electrons
in one valley and in a scalar field background. The Lorentz violation comes
from the difference between the Dirac electron and scalar mode velocities,
which should be expected when modelling the electronic and lattice excitations
in 2D materials. We extend the analytical methods developed in the context of
1+1 field theories to explore the effect of the Lorentz symmetry breaking in
the charge carrier density of 2D materials in the presence of a domain wall
with a kink profile. The width and the depth of the trapping potential from the
kink is controlled by the Lorentz violating term, which is reflected
analytically in the band structure and properties of the trapped states. Our
findings enlarge previous studies of the edge states obtained with domain wall
and in strained graphene nanoribbon in a chiral gauge theory.


  We argue that in order to provide a natural explanation of both neutrino mass
hierarchies and large neutrino mixing angles, as required by the atmospheric
neutrino data, a single right-handed neutrino must give the dominant
contribution to the 23 block of the light effective neutrino matrix, and
illustrate this mechanism in the framework of models with U(1) family
symmetries. Sub-dominant contributions from other right-handed neutrinos are
required to give small mass splittings appropriate to the small angle MSW
solution to the solar neutrino problem. We give general conditions for
achieving this in the framework of U(1) family symmetry models containing
arbitrary numbers of right-handed neutrinos, and show how the resulting
neutrino mass hierarchies and mixing angles may be expanded in terms of the
Wolfenstein parameter.


  We study an evolutionary prisoner's dilemma game with two layered graphs,
where the lower layer is the physical infrastructure on which the interactions
are taking place and the upper layer represents the connections for the
strategy adoption (learning) mechanism. This system is investigated by means of
Monte Carlo simulations and an extended pair-approximation method. We consider
the average density of cooperators in the stationary state for a fixed
interaction graph, while varying the number of edges in the learning graph.
According to the Monte Carlo simulations, the cooperation is modified
substantially in a way resembling a coherence-resonance-like behavior when the
number of learning edges is increased. This behavior is reproduced by the
analytical results.


  Despite ongoing global initiatives to reduce CO2 emissions, implementing
large-scale CO2 capture using amine solvents is fraught with economic
uncertainties and technical hurdles. The Rotating Packed Bed (RPB) presents a
promising alternative to traditional packed towers, offering compact design and
adaptability. Nonetheless, scaling RPB processes to an industrial level is
challenging due to the nascent nature of its application. The complexity of
designing RPB units, setting operating conditions, and evaluating process
performance adds layers of difficulty to the adoption of RPB-based systems in
industries. This study introduces an optimization-driven design and evaluation
for CO2 capture processes utilizing RPB columns. By employing detailed process
simulation, we aim to concurrently optimize unit design and operating
parameters, underscoring its advantage over conventional sequential approaches.
Our process design method integrates heuristic design recommendations as
constraints, resulting in 9.4% to 12.7% cost savings compared to conventional
sequential design methods. Furthermore, our comprehensive process-level
analysis reveals that using concentrated MEA solvent can yield total cost
savings of 13.4% to 25.0% compared to the standard 30wt% MEA solvent.
Additionally, the RPB unit can deliver an 8.5 to 23.6 times reduction in
packing volume. While the commercial-scale feasibility of RPB technology has
been established, the advancement of this field hinges on acquiring a broader
and more robust dataset from commercial-scale implementations. Employing
strategic methods like modularization could significantly reduce the entry
barriers for CO2 capture projects, facilitating their broader adoption and
implementation.


  Let $X_{1,n} \leq .... \leq X_{n,n}$ be the order statistics associated with
a sample $X_{1}, ...., X_{n}$ whose pertaining distribution function (%
\textit{df}) is $F$. We are concerned with the functional asymptotic behaviour
of the sequence of stochastic processes \begin{equation}
T_{n}(f,s)=\sum_{j=1}^{j=k}f(j)\left(\log X_{n-j+1,n}-\log
X_{n-j,n}\right)^{s}, \label{fme} \end{equation} indexed by some classes
$\mathcal{F}$ of functions $f:\mathbb{N}% ^{\ast}\longmapsto \mathbb{R}_{+}$
and $s \in ]0,+\infty[$ and where $k=k(n)$ satisfies \begin{equation*} 1\leq
k\leq n,k/n\rightarrow 0\text{as}n\rightarrow \infty . \end{equation*}
  \noindent We show that this is a stochastic process whose margins generate
estimators of the extreme value index when $F$ is in the extreme domain of
attraction. We focus in this paper on its finite-dimension asymptotic law and
provide a class of new estimators of the extreme value index whose performances
are compared to analogous ones. The results are next particularized for one
explicit class $\mathcal{F}$.


  Re-based superconductors provide a rich platform for the study of
unconventional superconductivity. We have investigated the superconducting
properties of Re$_{8}$NbTa, a new noncentrosymmetric cubic ($\alpha$-Mn
structure) rhenium-based ternary superconductor using transport, magnetization,
specific heat, and muon spin rotation/relaxation ($\mu$SR) measurements.
Specific heat and transverse field $\mu$SR measurements suggest moderately
coupled fully gapped superconductivity, well described by BCS theory. However,
our zero-field $\mu$SR measurements reveal a small internal field onsetting
around the superconducting T$_c$, indicating that the superconducting order
parameter breaks the time-reversal symmetry.


  We present VUV observations of transitions between doubly excited sextet
states in O3+, F4+ and Ne5+. Spectra were produced by collisions of an oxygen,
uorine and neon beam with a nitrogen gas jet target. Prepared beam-gas
experiment yields new and explicit information on doubly core-excited ions.
Some observed lines were assigned to the 1s2s2p3 6S-1s2p33s, 3d 6P
electric-dipole transitions in O3+, F4+ and Ne5+. Three lines have been
reassigned. Present data are the first explicit measurements on transitions
between sextet states in boronlike ions by beam-gas spectroscopy.


  This paper presents a novel quadratic projection based feature extraction
framework, where a set of quadratic matrices is learned to distinguish each
class from all other classes. We formulate quadratic matrix learning (QML) as a
standard semidefinite programming (SDP) problem. However, the con- ventional
interior-point SDP solvers do not scale well to the problem of QML for
high-dimensional data. To solve the scalability of QML, we develop an efficient
algorithm, termed DualQML, based on the Lagrange duality theory, to extract
nonlinear features. To evaluate the feasibility and effectiveness of the
proposed framework, we conduct extensive experiments on biometric recognition.
Experimental results on three representative biometric recogni- tion tasks,
including face, palmprint, and ear recognition, demonstrate the superiority of
the DualQML-based feature extraction algorithm compared to the current
state-of-the-art algorithms


  Spacetimes obtained by dimensional reduction along lattices containing a
lightlike direction can admit semigroup extensions of their isometry groups. We
show by concrete examples that such a semigroup can exhibit a natural order,
which in turn implies the existence of preferred coordinate charts on the
underlying space. Specifically, for spacetimes which are products of an
external Minkowski space with an internal two-dimensional Lorentzian space,
where one of the lightlike directions has a compact size, the preferred charts
consist of "infinite-momentum" frames on the internal space. This implies that
fields viewed from this preferred frame acquire extreme values; in particular,
some of the off-diagonal components of the higher-dimensional metric, which may
be regarded as gauge potentials for a field theory on the external Minkowski
factor, vanish. This raises the possibility of regarding known gauge theories
as part of more extended field multiplets which have been reduced in size since
they are perceived from within an extreme frame. In the case of an external
4-dimensional Minkowski spacetime times a two-dimensional Lorentzian cylinder,
the field content as seen in the preferred frame is that of a five-dimensional
Kaluza-Klein theory, where the electrodynamic potentials Am may depend, in
addition to the external spacetime coordinates, on a fifth coordinate along a
lightlike direction. The fact that the metric along this direction is zero
obstructs the generation of field equations from the Ricci tensor of the
overall metric.


  Recently, great progress has been made in the field of ultrasensitive
microwave detectors, reaching even the threshold for utilization in circuit
quantum electrodynamics. However, cryogenic sensors lack the compatibility with
broad-band metrologically traceable power absorption measurements at ultralow
powers, which limits their scope of applications. Here, we demonstrate such
measurements using an ultralow-noise nanobolometer which we extend by an
additional direct-current (dc) heater input. The tracing of the absorbed power
relies on comparing the response of the bolometer between radio frequency (rf)
and dc-heating powers traced to the Josephson voltage and quantum Hall
resistance. To illustrate this technique, we demonstrate methods to calibrate
the power that is delivered to the base temperature stage of a dilution
refrigerator using our in-situ power sensor. As an example, we demonstrate the
ability to measure accurately the attenuation of a coaxial input line between
the frequencies of 50 MHz and 7 GHz with an uncertainty down to 0.1 dB at
typical input power of -114 dBm.


  Consumers on a shopping mission often leverage both product search and
information seeking systems, such as web search engines and Question Answering
(QA) systems, in an iterative process to improve their understanding of
available products and reach a purchase decision. While product search is
useful for shoppers to find the actual products meeting their requirements in
the catalog, information seeking systems can be utilized to answer any
questions they may have to refine those requirements. The recent success of
Large Language Models (LLMs) has opened up an opportunity to bridge the gap
between the two tasks to help customers achieve their goals quickly and
effectively by integrating conversational QA within product search. In this
paper, we propose to recommend users Question-Answer (Q&A) pairs that are
relevant to their product search and can help them make a purchase decision. We
discuss the different aspects of the problem including the requirements and
characteristics of the Q&A pairs, their generation, and the optimization of the
Q&A recommendation task. We highlight the challenges, open problems, and
suggested solutions to encourage future research in this emerging area.


  At finite temperature and in presence of disorder, a one-dimensional elastic
interface displays different scaling regimes at small and large lengthscales.
Using a replica approach and a Gaussian Variational Method (GVM), we explore
the consequences of a finite interface width $\xi$ on the small-lengthscale
fluctuations. We compute analytically the static roughness $B(r)$ of the
interface as a function of the distance $r$ between two points on the
interface. We focus on the case of short-range elasticity and random-bond
disorder. We show that for a finite width $\xi$ two temperature regimes exist.
At low temperature, the expected thermal and random-manifold regimes,
respectively for small and large scales, connect via an intermediate `modified'
Larkin regime, that we determine. This regime ends at a temperature-independent
characteristic `Larkin' length. Above a certain `critical' temperature that we
identify, this intermediate regime disappears. The thermal and random-manifold
regimes connect at a single crossover lengthscale, that we compute. This is
also the expected behavior for zero width. Using a directed polymer
description, we also study via a second GVM procedure and generic scaling
arguments, a modified toy model that provides further insights on this
crossover. We discuss the relevance of the two GVM procedures for the roughness
at large lengthscale in those regimes. In particular we analyze the scaling of
the temperature-dependent prefactor in the roughness $B(r)\sim T^{2
\text{\thorn}} r^{2 \zeta}$ and its corresponding exponent $\text{\thorn}$. We
briefly discuss the consequences of those results for the quasistatic creep law
of a driven interface, in connection with previous experimental and numerical
studies.


  Gamow-Teller (GT) states in N=Z nuclei with the mass number A from 48 to 64
are studied by using Hartree-Fock-Bogoliubov + quasi-particle random phase
approximation (HFB+QRPA) with Skyrme interactions. The isoscalar spin-triplet
(T=0,S=1) pairing interaction is taken into account in QRPA calculations. It is
found in the context of SU(4) symmetry in the spin-isospin space that the GT
strength of lower energy excitations is largely enhanced by the T=0 pairing
interaction which works cooperatively with the T=1 pairing interaction in the
ground state. A two-peaked structure observed recently in $(p,n)$ reaction on
$^{56}$Ni can be considered as a manifestation of the role of T=0 pairing in
the GT collective states.


  Recent numerical simulations and analytical models of magnetically collimated
plasma outflows from a uniformly rotating central gravitating object and/or a
Keplerian accretion disk have shown that relatively low mass and magnetic
fluxes reside in the produced jet. Observations however indicate that in some
cases, as in jets of YSO's, the collimated outflow carries higher fluxes than
these simulations predict. A solution to this problem is proposed here by
assuming that jets with high mass flux originate in a central source which
produces a noncollimated outflow provided that this source is surrounded by a
rapidly rotating accretion disk. The relatively faster rotating disk produces a
collimated wind which then forces all the enclosed outflow from the central
source to be collimated too. This conclusion is confirmed by self-consistent
numerical solutions of the full set of the MHD equations.


  Famous for the extraordinary richness of its molecular content, the Sgr B2
molecular cloud complex is the prime target in the long-standing search for
ever more complex species. We have completed a molecular line survey of the hot
dense cores Sgr B2(N) and Sgr B2(M) in the 3 mm wavelength range with the IRAM
30 m telescope. We performed the analysis of this huge data set by modeling the
whole spectrum at once in the LTE approximation. Ongoing analyses yield an
average line density of about 100 features/GHz above 3 sigma for Sgr B2(N),
emitted and/or absorbed by a total of 51 molecular species. We find lines from
60 rare isotopologues and from 41 vibrationally excited states in addition to
the main species, vibrational ground state lines. For Sgr B2(M), we find about
25 features/GHz above 3 sigma, from 41 molecular species plus 50 isotopologues
and 20 vibrationally excited states. Thanks to the constant updates to the
Cologne Database for Molecular Spectroscopy, we are working our way through the
assignment of the unidentified features, currently 40% and 50% above 3 sigma
for Sgr B2(N) and Sgr B2(M), respectively.


  We present view-synthesis autoencoders (VSA) in this paper, which is a
self-supervised learning framework designed for vision transformers. Different
from traditional 2D pretraining methods, VSA can be pre-trained with multi-view
data. In each iteration, the input to VSA is one view (or multiple views) of a
3D object and the output is a synthesized image in another target pose. The
decoder of VSA has several cross-attention blocks, which use the source view as
value, source pose as key, and target pose as query. They achieve
cross-attention to synthesize the target view. This simple approach realizes
large-angle view synthesis and learns spatial invariant representation, where
the latter is decent initialization for transformers on downstream tasks, such
as 3D classification on ModelNet40, ShapeNet Core55, and ScanObjectNN. VSA
outperforms existing methods significantly for linear probing and is
competitive for fine-tuning. The code will be made publicly available.


  Capturing the image of the shadow cast by the event horizon of an illuminated
black hole is, at the most basic level, an experiment of extreme light
deflection in a strongly curved spacetime. As such, the properties of an imaged
shadow can be used to probe the general relativistic Kerr nature of
astrophysical black holes. As an example of this prospect, it is commonly
asserted that a shadow can test the validity of the theory's famous `no hair
theorem' for the black hole's mass and spin multipole moments. In this paper,
we assess this statement by calculating the shadow's equatorial radius in
spacetimes with an arbitrary multipolar structure and within a slow rotation
approximation. We find that when moments higher than the quadrupole are taken
into account, the shadow acquires a high degree of degeneracy as a function of
the deviation from the Kerr multipole moments. The results of our analysis
suggest that dark objects with strongly non-Kerr multipolar structure could
nevertheless produce a Kerr-like shadow with its characteristic quasi-circular
shape.


  Achieving thermal equilibrium in two-dimensional lattices of interacting
nanomagnets has been a key issue on the route to study exotic phases in
artificial frustrated magnets. We revisit this issue in artificial
one-dimensional kagom\'e spin chains. Imaging arrested micro-states generated
by a field demagnetization protocol and analyzing their pairwise spin
correlations in real space, we unveil a non-equilibrated physics. Remarkably,
this physics can be reformulated into an at-equilibrium one by rewriting the
associated spin Hamiltonian in such a way that one of the coupling constants is
quenched. We ascribe this effective behavior to a kinetic hinderance during the
demagnetization protocol, which induces the formation of local flux closure
spin configurations that sometimes compete with the magnetostatic interaction.


  The Schwarzschild metric has a divergent energy density at the horizon, which
motivates a new approach to black holes. If matter is spread uniformly
throughout the interior of a supermassive black hole, with mass $M\sim M_\star=
2.34 10^8M_\odot$, it may arise from a Bose-Einstein condensate of densely
packed H-atoms. Within the Relativistic Theory of Gravitation with a positive
cosmological constant, a bosonic quantum field is coupled to the curvature
scalar. In the Bose-Einstein condensed groundstate an exact, selfconsistent
solution for the metric is presented. It is regular with a specific shape at
the origin. The redshift at the horizon is finite but large, $z\sim
10^{14}$$M_\star/M$. The binding energy remains as an additional parameter to
characterize the BH; alternatively, the mass observed at infinity can be any
fraction of the rest mass of its constituents.


  Total reflection x-ray fluorescence (TXRF) spectroscopy has seen a remarkable
progress over the past years. Numerous applications in basic and applied
sciences prove its importance. The large spectral background which is a major
detrimental factor in the conventional x-ray fluorescence technique, limits the
element detection sensitivities of the technique to ppm range. This spectral
background reduces to a great extent in the TXRF technique due to the low
extinction depth of the primary incident x-ray beam. In synchrotron radiation
(SR) based TXRF measurements the spectral background reduces further because of
the polarization of the synchrotron x-ray beam. Here, we discuss in detail the
influence of synchrotron polarization on the spectral background in a
fluorescence spectrum and its significance towards TXRF detection
sensitivities. We provide a detailed theoretical description and show that how
anisotropic scattering probability densities of the Compton and Elastic
scattered x-rays depend on the scattering angle ({\theta}) and azimuthal angle
({\phi}) in the polarization plane of the SR beam.


  We present the results of our analysis of a high resolution (R ~ 30000)
infrared spectrum of V4334 Sgr (Sakurai's Object) around the first overtone CO
bands, obtained in 1998 July. The 12CO and 13CO bands are well-resolved, and we
compute synthetic hydrogen-deficient model atmosphere spectra to determine the
12C/13C ratio. We find 12C/13C ~ 4 +/-1, consistent with the interpretation of
V4334 Sgr as an object that has undergone a very late thermal pulse.


  Model order reduction is the approximation of dynamical systems into
equivalent systems with smaller order. Model reduction has been studied
extensively for different types of systems. In this paper, we present two
methods for multi input multi output linear systems. These methods are based on
solvents, also called block poles. These methods are particularly suitable if
the given system is in matrix transfer function form. The first method
eliminates solvents one by one whereas, the second method can eliminate
multiple solvents at the same time. The two presented methods are implemented
in MATLAB in order to provide a systematic method for the model order reduction
of MIMO linear systems.


  We construct Eberlein almost periodic functions $ f_j : J \to H$ so that
  $||f_1(\cdot)||$ is not ergodic and thus not Eberlein almost periodic and
$||f_2(.)||$ is Eberlein almost periodic, but $f_1$ and $f_2$ are not pseudo
almost periodic, the Parseval equation for them fails, where $J=\r_+$ or $\r$
and $H$ is a Hilbert space. This answers several questions posed by Zhang and
Liu [18].


  We study $B_{\small (s)}\to \phi\rho$ decays in a perturbative QCD approach
based on $k_T$ factorization. In this approach, we calculate factorizable and
non-factorizable contributions, there are no annihilation contributions due to
quark content. We get the branching ratios and polarization fractions for
$B_{\small (s)}\to \phi\rho$ decays . Our predictions are consistent with the
current experimental data.


  We introduce a novel mechanism that reveals finite time singularities within
the 1D De Gregorio model and the 3D incompressible Euler equations. Remarkably,
we do not construct our blow up using self-similar coordinates, but build it
from infinitely many regions with vorticity, separated by vortex-free regions
in between. It yields solutions of the 3D incompressible Euler equations in
$\mathbb{R}^3\times [-T,0]$ such that the velocity is in the space
$C^{\infty}(\mathbb{R}^3 \setminus \{0\})\cap C^{1,\alpha}\cap L^2$ for times
$t\in (-T,0)$ and is not $C^1$ at time 0.


  Compact groups (CGs) provide an environment in which interactions between
galaxies and with the intra-group medium enable and accelerate galaxy
transitions from actively star forming to quiescent. Galaxies in transition
from active to quiescent can be selected, by their infrared (IR) colors, as
canyon or infrared transition zone (IRTZ) galaxies. We used a sample of CG
galaxies with IR data from the Wide Field Infrared Survey Explorer (WISE)
allowing us to calculate the stellar mass and star formation rate (SFR) for
each galaxy. Furthermore, we present new CO(1-0) data for 27 galaxies and
collect data from the literature to calculate the molecular gas mass for a
total sample of 130 galaxies. This data set allows us to study the difference
in the molecular gas fraction (Mmol/Mstar) and star formation efficiency
(SFE=SFR/Mmol) between active, quiescent, and transitioning (i.e., canyon and
IRTZ) galaxies. We find that transitioning galaxies have a mean molecular gas
fraction and a mean SFE that are significantly lower than those of actively
star-forming galaxies. The molecular gas fraction is higher than that of
quiescent galaxies, whereas the SFE is similar. These results indicate that the
transition from actively star-forming to quiescent in CG galaxies goes along
with a loss of molecular gas, possibly due to tidal forces exerted from the
neighboring galaxies or a decrease in the gas density. In addition, the
remaining molecular gas loses its ability to form stars efficiently, possibly
owing to turbulence perturbing the gas, as seen in other, well-studied examples
such as Stephan's Quintet and HCG~57. Thus, the amount and properties of
molecular gas play a crucial role in the environmentally driven transition of
galaxies from actively star forming to quiescent.


  The paper was withdrawn due to another possible solution to the dataset that
is significantly different in nature. This issue will be addressed shortly and
clarified with an additional data point.


  Inspired by our recent works on information paradox in black holes, which
exploit various foundational intricacies of quantum mechanics, here we propose
a novel connection between the spacetime geometry and quantum entanglement of
matter fields "living" in that geometry. We highlight, as a natural consequence
of those studies, that gravitational field might have a natural tendency of
reducing entanglement between two quantum states.


  This paper deals with the problem of robust output regulation of systems
governed by nonlinear contraction semigroups. After adding an integral action
to the system, we design a feedback law based on the so-called forwarding
approach. For small constant perturbations, we give sufficient conditions for
the existence of a locally exponentially stable equilibrium at which the output
coincides with the reference. Under additional assumptions, global asymptotic
stability is achieved. All these conditions are investigated in the case of
semilinear systems, and examples of application are given.


  In this work, a version of Fermat's principle for causal curves with the same
energy in time orientable Finsler spacetimes is proved. We calculate the
secondvariation of the {\it time arrival functional} along a geodesic in terms
of the index form associated with the Finsler spacetime Lagrangian. Then the
character of the critical points of the time arrival functional is investigated
and a Morse index theorem in the context of Finsler spacetime is presented.


  In this paper, we propose an access control method for object detection
models. The use of encrypted images or encrypted feature maps has been
demonstrated to be effective in access control of models from unauthorized
access. However, the effectiveness of the approach has been confirmed in only
image classification models and semantic segmentation models, but not in object
detection models. In this paper, the use of encrypted feature maps is shown to
be effective in access control of object detection models for the first time.


  Let A and B be separable nuclear continuous C(X)-algebras over a finite
dimensional compact metrizable space X. It is shown that an element $\sigma$ of
the parametrized Kasparov group KK_X(A,B) is invertible if and only if all its
fiberwise components $\sigma_x\in KK(A(x),B(x))$ are invertible. This criterion
does not extend to infinite dimensional spaces since there exist nontrivial
unital separable continuous fields over the Hilbert cube with all fibers
isomorphic to the Cuntz algebra O_2. Several applications to continuous fields
of Kirchberg algebras are given. It is also shown that if each fiber of a
separable nuclear continuous C(X)-algebra A over a finite dimensional locally
compact space X satisfies the UCT, then A satisfies the UCT.


  This is my master thesis. Unfortunately it is written in Italian, but maybe
somebody will find it helpful when it comes to Evans Potentials


  We prove the existence of the flow by curvature of regular planar networks
starting from an initial network which is non-regular. The proof relies on a
monotonicity formula for expanding solutions and a local regularity result for
the network flow in the spirit of B. White's local regularity theorem for mean
curvature flow. We also show a pseudolocality theorem for mean curvature flow
in any codimension, assuming only that the initial submanifold can be locally
written as a graph with sufficiently small Lipschitz constant.


  This is the second paper in a series of papers showing the results of
extrasolar planet population synthesis calculations. In the companion paper
(Paper I), we have presented in detail our methods. By applying an
observational detection bias for radial velocity surveys, we identify the
potentially detectable synthetic planets. The properties of these planets are
compared in quantitative statistical tests with the properties of a carefully
selected sub-population of actual exoplanets. We use a two dimensional
Kolmogorov-Smirnov test to compare the mass-distance distributions of synthetic
and observed planets, as well as 1D KS tests to compare the mass, the semimajor
axis and the [Fe/H] distributions. We find that some models can account to a
reasonable degree of significance for the observed properties. We concurrently
account for many other observed features, e.g. the "metallicity effect". This
gives us confidence that our model captures several essential features of giant
planet formation. Our simulations allow us also to extract the properties of
the underlying exoplanet population that are not yet detectable. For example,
we have derived the planetary initial mass function (PIMF) and have been led to
conclude that the planets detected so far represent only the tip of the
iceberg. The PIMF can also be used to predict how the detectable extrasolar
planet population will change as the precision of radial velocity surveys
improves to an extreme precision of 0.1 m/s.


  The symmetric periodic Anderson model is well known to capture the essential
physics of Kondo insulator materials. Within the framework of dynamical
mean-field theory, we develop a local moment approach to its single-particle
dynamics in the paramagnetic phase. The approach is intrinsically
non-perturbative, encompasses all energy scales and interaction strengths, and
satisfies the low-energy dictates of Fermi liquid theory. It captures in
particular the strong coupling behaviour and exponentially small quasiparticle
scales characteristic of the Kondo lattice regime, as well as simple
perturbative behaviour in weak coupling. Particular emphasis is naturally given
to strong coupling dynamics, where the resultant clean separation of energy
scales enables the scaling behaviour of single-particle spectra to be obtained.


  We consider a singularly perturbed reaction diffusion problem as a first
order two-by-two system. Using piecewise discontinuous polynomials for the
first component and $H_{div}$-conforming elements for the second component we
provide a convergence analysis on layer adapted meshes and an optimal
convergence order in a balanced norm that is comparable with a balanced
$H^2$-norm for the second order formulation.


  We obtained a 5 ksec deep Chandra X-ray Observatory ACIS-I map of the 9.3
square degree Bootes field of the NOAO Deep Wide-Field Survey. Here we describe
the data acquisition and analysis strategies leading to a catalog of 4642
(3293) point sources with 2 or more (4 or more) counts, corresponding to a
limiting flux of roughly 4(8)x10^{-15} erg cm^{-2}s^{-1} in the 0.5-7 keV band.
These Chandra XBootes data are unique in that they consitute the widest
contiguous X-ray field yet observed to such a faint flux limit. Because of the
extraordinarily low background of the ACIS, we expect only 14% (0.7%) of the
sources to be spurious. We also detected 43 extended sources in this survey.
The distribution of the point sources among the 126 pointings (ACIS-I has a 16
x 16 arcminute field of view) is consistent with Poisson fluctuations about the
mean of 36.8 sources per pointing. While a smoothed image of the point source
distribution is clumpy, there is no statistically significant evidence of large
scale filamentary structure. We do find however, that for theta>1 arcminute,
the angular correlation function of these sources is consistent with previous
measurements, following a power law in angle with slope -0.7. In a 1.4 deg^{2}
sample of the survey, approximately 87% of the sources with 4 or more counts
have an optical counterpart to R ~26 mag. As part of a larger program of
optical spectroscopy of the NDWFS Bootes area, spectra have been obtained for
\~900 of the X-ray sources, most of which are QSOs or AGN.


  The synergy between the Fermi-LAT and ground-based Cherenkov telescope arrays
gives us the opportunity for the first time to characterize the high energy
emission (100 MeV - 10 TeV) from more than 30 blazars. In this study we
performed a Fermi-LAT spectral analysis for all TeV-detected blazars and
combined it with archival TeV spectra. Our results for low synchrotron-peaked
BL Lacs (LBL) show hints of absorption features in the GeV band that could be
interpreted as internal opacity at the source. We note that simple or broken
power laws cannot describe all the observed GeV-TeV spectra and more complex
spectral shapes seem required.


  We show that on the unit disc cotangent bundle of flat Riemannian tori, all
normalized capacities coincide with twice the systole. The same result holds
for flat, reversible Finsler tori and normalized capacities that are greater
than or equal to the Hofer-Zehnder capacity.


  We establish a variety of extensions to the Erdos-Rado Theorem, particularly
involving ordinal numbers, and always involving ordinary partition relations.
Most of the results can be regarded as consequences of the Ramification
Principle, interpreted appropriately. Some of these problems have been open for
a long time. There is a detailed summary at the beginning of the paper. The
paper is scheduled to appear as part of the proceedings of the Banff meeting
held in 1991.


  Finding data is a necessary precursor to being able to reuse data, although
relatively little large-scale empirical evidence exists about how researchers
discover, make sense of and (re)use data for research. This study presents
evidence from the largest known survey investigating how researchers discover
and use data that they do not create themselves. We examine the data needs and
discovery strategies of respondents, propose a typology for data reuse and
probe the role of social interactions and literature search in data discovery.
We consider how data communities can be conceptualized according to data uses
and propose practical applications of our findings for designers of data
discovery systems and repositories. Specifically, we consider how to design for
a diversity of practices, how communities of use can serve as an entry point
for design and the role of metadata in supporting both sensemaking and social
interactions.


  We report the detection of complex organic molecules in the young
protostellar outflow L1157. We identify lines from HCOOCH3, CH3CN, HCOOH and
C2H5OH at the position of the B1 shock in the blueshifted lobe, making it the
first time that complex species have been detected towards a molecular outflow
powered by a young low-mass protostar. The time scales associated with the warm
outflow gas (< 2,000 yr) are too short for the complex molecules to have formed
in the gas phase after the shock-induced sputtering of the grain mantles. It is
more likely that the complex species formed in the surface of grains and were
then ejected from the grain mantles by the shock. The formation of complex
molecules in the grains of low-mass star forming regions must be relatively
efficient, and our results show the importance of considering the impact of
outflows when studying complex molecules around protostars. The relative
abundance with respect to methanol of most of the detected complex molecules is
similar to that of hot cores and molecular clouds in the galactic center
region, which suggests that the mantle composition of the dust in the L1157
dark cloud is similar to dust in those regions.


  Three dimensional Dirac semimetals are stable against weak potential
disorder, but not against strong disorder. In the language of renormalization
group, such stability stems from the irrelevance of weak disorder in the
vicinity of the noninteracting Gaussian fixed point. However, beyond a
threshold, potential disorder can take Dirac semimetals into a compressible
diffusive metallic phase through a quantum phase transition (QPT), where
density of states at zero energy, quasiparticle lifetime and metallic
conductivity at $T=0$, are finite. Universal behavior of such unconventional
QPT is described within the framework of an $\epsilon(=d-2)$-expansion near the
lower critical dimension. Various exponents near this QCP are obtained after
performing a two loop perturbative expansion in the vanishing replica limit and
we demonstrate that the theory is renormalizable at least to two loop order.We
argue that such QPT is always continuous in nature, share same university class
with a similar transition driven by odd-parity disorder, critical exponents are
independent of flavor number of Dirac femrions and thus can be germane to
disordered Cd$_3$As$_2$, Na$_3$Bi. Scaling behaviors of various measurable
quantities, such as specific heat, density of states across such QPT are
proposed.


  High density and uniformity sub-100nm surface oxidized silicon nanocone
forest structure is created and integrated onto the existing texturization
microstructures on photovoltaic device surface by a one-step high throughput
plasma enhanced texturization method. We suppressed the broadband optical
reflection on chemically textured grade-B silicon solar cells for up to 70.25%
through this nanomanufacturing method. The performance of the solar cell is
improved with the short circuit current increased by 7.1%, fill factor
increased by 7.0%, conversion efficiency increased by 14.66%. Our method
demonstrates the potential to improve the photovoltaic device performance with
low cost high and throughput nanomanufacturing technology.


  Massive Open Online Courses (MOOCs) have gained tremendous popularity in the
last few years. Thanks to MOOCs, millions of learners from all over the world
have taken thousands of high-quality courses for free. Putting together an
excellent MOOC ecosystem is a multidisciplinary endeavour that requires
contributions from many different fields. Artificial intelligence (AI) and data
mining (DM) are two such fields that have played a significant role in making
MOOCs what they are today. By exploiting the vast amount of data generated by
learners engaging in MOOCs, DM improves our understanding of the MOOC ecosystem
and enables MOOC practitioners to deliver better courses. Similarly, AI,
supported by DM, can greatly improve student experience and learning outcomes.
In this survey paper, we first review the state-of-the-art artificial
intelligence and data mining research applied to MOOCs, emphasising the use of
AI and DM tools and techniques to improve student engagement, learning
outcomes, and our understanding of the MOOC ecosystem. We then offer an
overview of key trends and important research to carry out in the fields of AI
and DM so that MOOCs can reach their full potential.


  We propose and study a model where, for the first time, two aspects are
present: parity conservation and infinitely many absorbing states. Whereas
steady-state simulations show that the static critical behaviour is not
affected by the presence of multiple absorbing configurations, the influence of
the initial state associated with the presence of slowly decaying memory
effects is clearly displayed in time dependent simulations. We report results
of a detailed investigation of the dependence of critical spreading exponents
on the initial particle density.


  Functional Electrical Stimulation (FES) systems are successful in restoring
motor function and supporting paralyzed users. Commercially available FES
products are open loop, meaning that the system is unable to adapt to changing
conditions with the user and their muscles which results in muscle fatigue and
poor stimulation protocols. This is because it is difficult to close the loop
between stimulation and monitoring of muscle contraction using adaptive
stimulation. FES causes electrical artefacts which make it challenging to
monitor muscle contractions with traditional methods such as electromyography
(EMG). We look to overcome this limitation by combining FES with novel
mechanomyographic (MMG) sensors to be able to monitor muscle activity during
stimulation in real time. To provide a meaningful task we built an FES cycling
rig with a software interface that enabled us to perform adaptive recording and
stimulation, and then combine this with sensors to record forces applied to the
pedals using force sensitive resistors (FSRs), crank angle position using a
magnetic incremental encoder and inputs from the user using switches and a
potentiometer. We illustrated this with a closed-loop stimulation algorithm
that used the inputs from the sensors to control the output of a programmable
RehaStim 1 FES stimulator (Hasomed) in real-time. This recumbent bicycle rig
was used as a testing platform for FES cycling. The algorithm was designed to
respond to a change in requested speed (RPM) from the user and change the
stimulation power (% of maximum current mA) until this speed was achieved and
then maintain it.


  For distances large relative to the electron Compton wavelength, the Maxwell
and gravitational fields from a bound electron in its groundstate are
essentially those from a rotating, charged, massive point particle. For
distances small relative to the electron Compton wavelength, the corresponding
Maxwell fields and General Relativity metric, Riemann and Einstein tensors
become bounded, showing that, for this example, quantum effects remove the
corresponding classical singularities in electromagnetism and General
Relativity. The asymptotic magnetic dipole field from the bound electron
produces a constant magnetic field of several Tesla, aligned along the spin
axis of the electron, at the singularity position. The corresponding apparent
mass density from the gravitational field from the bound electron is about
2kgm$^{-3}$, at the singularity position.


  The temperature profile of two different BSCCO 2212 coils has been analyzed.
The profiles are obtained from thermocouples imbedded in the windings during
the heat treatment that activates the 2212. The melting and freezing of the
2212 is clearly observed. A model that describes the data and can be used to
guide the processing of new coils has been developed.


  Meila (2018) introduces an optimization based method called the Sublevel Set
method, to guarantee that a clustering is nearly optimal and "approximately
correct" without relying on any assumptions about the distribution that
generated the data. This paper extends the Sublevel Set method to the
cost-based hierarchical clustering paradigm proposed by Dasgupta (2016).


  We study the influence of the virtual pion cloud in nuclear matter at finite
densities and temperatures on the structure of the rho- and omega-mesons. The
in-matter spectral function of the pion is obtained within a selfconsistent
scheme of coupled Dyson equations where the coupling to the nucleon and the
Delta(1232)-isobar resonance is taken into account. The selfenergies are
determined using a two-particle irreducible (2PI) truncation scheme
(Phi-derivable approximation) supplemented by Migdal's short range correlations
for the particle-hole excitations. The so obtained spectral function of the
pion is then used to calculate the in-medium changes of the vector-meson
spectral functions. With increasing density and temperature a strong interplay
of both vector-meson modes is observed. The four-transversality of the
polarisation tensors of the vector-mesons is achieved by a projector technique.
The resulting spectral functions of both vector-mesons and, through vector
dominance, the implications of our results on the dilepton spectra are studied
in their dependence on density and temperature.


  Before global-scale quantum networks become operational, it is important to
consider how to evaluate their performance so that they can be built to achieve
the desired performance. We propose two practical figures of merit for the
performance of a quantum network: the average connection time and the average
largest entanglement cluster size. These quantities are based on the generation
of elementary links in a quantum network, which is a crucial initial
requirement that must be met before any long-range entanglement distribution
can be achieved and is inherently probabilistic with current implementations.
We obtain bounds on these figures of merit for a particular class of quantum
repeater protocols consisting of repeat-until-success elementary link
generation followed by joining measurements at intermediate nodes that extend
the entanglement range. Our results lead to requirements on quantum memory
coherence times, requirements on repeater chain lengths in order to surpass the
repeaterless rate limit, and requirements on other aspects of quantum network
implementations. These requirements are based solely on the inherently
probabilistic nature of elementary link generation in quantum networks, and
they apply to networks with arbitrary topology.


  We study topological full groups attached to groupoid models for left regular
representations of Garside categories. Groups arising in this way include
Thompson's group $V$ and many of its variations such as R\"over-Nekrashevych
groups. Our key observation is that a Garside structure for the underlying
small category induces a new Garside structure for a new small category of
bisections, and that our topological full group coincides with the fundamental
group of the enveloping groupoid of the new category. As a consequence, we
solve the word problem and identify general criteria for establishing
finiteness properties of our topological full groups. In particular, we show
that topological full groups arising from products of shifts of finite type are
of type ${\rm F}_{\infty}$, answering a natural question left open by Matui.


  We study the level spacing distribution for the spectrum of a point scatterer
on a flat torus. In the 2-dimensional case, we show that in the weak coupling
regime the eigenvalue spacing distribution coincides with that of the spectrum
of the Laplacian (ignoring multiplicties), by showing that the perturbed
eigenvalues generically clump with the unperturbed ones on the scale of the
mean level spacing. We also study the three dimensional case, where the
situation is very different.