  We review X-ray plasma diagnostics based on the line ratios of He-like ions.
Triplet/singlet line intensities can be used to determine electronic
temperature and density, and were first developed for the study of the solar
corona. Since the launches of the X-ray satellites Chandra and XMM-Newton,
these diagnostics have been extended and used (from CV to Si XIII) for a wide
variety of astrophysical plasmas such as stellar coronae, supernova remnants,
solar system objects, active galactic nuclei, and X-ray binaries. Moreover, the
intensities of He-like ions can be used to determine the ionization process(es)
at work, as well as the distance between the X-ray plasma and the UV emission
source for example in hot stars. In the near future thanks to the next
generation of X-ray satellites (e.g., Astro-H and IXO), higher-Z He-like lines
(e.g., iron) will be resolved, allowing plasmas with higher temperatures and
densities to be probed. Moreover, the so-called satellite lines that are formed
closed to parent He-like lines, will provide additional valuable diagnostics to
determine electronic temperature, ionic fraction, departure from ionization
equilibrium and/or from Maxwellian electron distribution.


  The dressing method based on the $2\times2$ matrix $\bar\partial$-problem is
generalized to study the canonical form of AB equations. The soliton solutions
for the AB equations are given by virtue of the properties of Cauchy matrix.
Asymptotic behaviors of the $N$-soliton solution are discussed.


  We present a study on the discoverability of temporarily captured orbiters
(TCOs) by present day or near-term anticipated ground-based and space-based
facilities. TCOs (Granvik et al. 2012) are potential targets for spacecraft
ren- dezvous or human exploration (Chyba et al. 2014) and provide an
opportunity to study the population of the smallest asteroids in the solar
system. We find that present day ground-based optical surveys such as
Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A
targeted survey conducted with the Subaru telescope can discover TCOs in the
0.5 m to 1.0 m diameter size range in about 5 nights of observing. Furthermore,
we discuss the application of space-based infrared surveys, such as NEOWISE,
and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in
discovering TCOs. These systems can detect TCOs but at a uninteresting rate.
Finally, we discuss the application of bi-static radar at Arecibo and Green
Bank to discover TCOs. Our radar simulations are strongly dependent on the
rotation rate distribution of the smallest asteroids but with an optimistic
distribution we find that these systems have > 80% chance of detecting a > 10
cm diameter TCO in about 40 h of operation.


  There are presented certain results on extending continuous linear operators
defined on spaces of E-valued continuous functions (defined on a compact
Hausdorff space X) to linear operators defined on spaces of E-valued measurable
functions in a way such that uniformly bounded sequences of functions that
converge pointwise in the weak (or norm) topology of E are sent to sequences
that converge in the weak, norm or weak* topology of the target space. As an
application, a new description of uniform closures of convex subsets of C(X,E)
is given. Also new and strong results on integral representations of continuous
linear operators defined on C(X,E) are presented. A new classes of vector
measures are introduced and various bounded convergence theorems for them are
proved.


  We obtain a complete characterization of the weak-type $(1,1)$ for Haar shift
operators in terms of generalized Haar systems adapted to a Borel measure $\mu$
in the operator-valued setting. The main technical tool in our method is a
noncommutative Calder\'on-Zygmund decomposition valid for arbitrary Borel
measures.


  The paper presents the professor-student network of Nobel laureates in
economics. 74 of the 79 Nobelists belong to one family tree. The remaining 5
belong to 3 separate trees. There are 350 men in the graph, and 4 women. Karl
Knies is the central-most professor, followed by Wassily Leontief. No classical
and few neo-classical economists have left notable descendants. Harvard is the
central-most university, followed by Chicago and Berlin. Most candidates for
the Nobel prize belong to the main family tree, but new trees may arise for the
students of Terence Gorman and Denis Sargan.


  Pure CO ice has been irradiated with electrons of energy in the range
$150-1000$~eV with the Interstellar Energetic-Process System (IEPS). The main
products of irradiation are carbon chains C$_n$ ($n=3$, 5, 6, 8, 9, 10, 11,
12), suboxides, C$_n$O ($n=2$, 3, 4, 5, 6, 7), and C$_n$O$_2$ ($n=1$, 3, 4, 5,
7) species. \ce{CO2} is by far the most abundant reaction product in all the
experiments. The destruction cross-section of CO peaks at about 250 eV,
decreases with the energy of the electrons and is more than one order of
magnitude higher than for gas-phase CO ionization. The production cross-section
of carbon dioxide has been also derived and is characterized by the competition
between chemistry and desorption.
  Desorption of CO and of new species during the radiolysis follows the
electron distribution in the ice. Low energy electrons having short penetration
depths induce significant desorption. Finally, as the ice thickness approaches
the electron penetration depth the abundance of the products starts to
saturate. Implications on the atmospheric photochemistry of cold planets
hosting surface CO ices are also discussed.


  We present the relation between the star formation rate surface density,
$\Sigma_{\rm SFR}$, and the hydrostatic mid-plane pressure, P$_{\rm h}$, for
4260 star-forming regions of kpc size located in 96 galaxies included in the
EDGE-CALIFA survey covering a wide range of stellar masses and morphologies. We
find that these two parameters are tightly correlated, exhibiting smaller
scatter and strong correlation in comparison to other star-forming scaling
relations. A power-law, with a slightly sub-linear index, is a good
representation of this relation. Locally, the residuals of this correlation
show a significant anti-correlation with both the stellar age and metallicity
whereas the total stellar mass may also play a secondary role in shaping the
$\Sigma_{\rm SFR}$ - P$_{\rm h}$ relation. For our sample of active
star-forming regions (i.e., regions with large values of H$\alpha$ equivalent
width), we find that the effective feedback momentum per unit stellar mass
($p_\ast/m_\ast$),measured from the P$_{\rm h}$ / $\Sigma_{\rm SFR}$ ratio
increases with P$_{\rm h}$. The median value of this ratio for all the sampled
regions is larger than the expected momentum just from supernovae explosions.
Morphology of the galaxies, including bars, does not seem to have a significant
impact in the $\Sigma_{\rm SFR}$ - P$_{\rm h}$ relation. Our analysis suggests
that self regulation of the $\Sigma_{\rm SFR}$ at kpc scales comes mainly from
momentum injection to the interstellar medium from supernovae explosions.
However, other mechanism in disk galaxies may also play a significant role in
shaping the $\Sigma_{\rm SFR}$ at local scales. Our results also suggest that
P$_{\rm h}$ can be considered as the main parameter that modulates star
formation at kpc scales, rather than individual components of the baryonic
mass.


  We investigate the task of modeling open-domain, multi-turn, unstructured,
multi-participant, conversational dialogue. We specifically study the effect of
incorporating different elements of the conversation. Unlike previous efforts,
which focused on modeling messages and responses, we extend the modeling to
long context and participant's history. Our system does not rely on handwritten
rules or engineered features; instead, we train deep neural networks on a large
conversational dataset. In particular, we exploit the structure of Reddit
comments and posts to extract 2.1 billion messages and 133 million
conversations. We evaluate our models on the task of predicting the next
response in a conversation, and we find that modeling both context and
participants improves prediction accuracy.


  We investigate the form and dynamics of shock-acoustic waves generated by
earthquakes. We use the method for detecting and locating the sources of
ionospheric impulsive disturbances, based on using data from a global network
of receivers of the GPS navigation system and requiring no a priori information
about the place and time of associated effects. The practical implementation of
the method is illustrated by a case study of earthquake effects in Turkey
(August 17, and November 12, 1999), in Southern Sumatera (June 4, 2000), and
off the coast of Central America (January 13, 2001). It was found that in all
instances the time period of the ionospheric response is 180-390 s, and the
amplitude exceeds by a factor of two as a minimum the standard deviation of
background fluctuations in total electron content in this range of periods
under quiet and moderate geomagnetic conditions. The elevation of the wave
vector varies through a range of 20-44 degree, and the phase velocity
(1100-1300 m/s) approaches the sound velocity at the heights of the ionospheric
F-region maximum. The calculated (by neglecting refraction corrections)
location of the source roughly corresponds to the earthquake epicenter. Our
data are consistent with the present views that shock-acoustic waves are caused
by a piston-like movement of the Earth surface in the zone of an earthquake
epicenter.


  This report describes the submission system of the GIST-AiTeR team at the
2022 VoxCeleb Speaker Recognition Challenge (VoxSRC) Track 4. Our system mainly
includes speech enhancement, voice activity detection , multi-scaled speaker
embedding, probabilistic linear discriminant analysis-based speaker clustering,
and overlapped speech detection models. We first construct four different
diarization systems according to different model combinations with the best
experimental efforts. Our final submission is an ensemble system of all the
four systems and achieves a diarization error rate of 5.12% on the challenge
evaluation set, ranked third at the diarization track of the challenge.


  We experimentally demonstrate and theoretically explain the onset of optical
frequency combs in a simple cavity-enhanced second-harmonic-generation system,
exploiting second-order nonlinear interactions. Two combs are simultaneously
generated around the fundamental pump frequency, with a spectral bandwidth up
to about 10 nm, and its second harmonic. We observe different regimes of
generation, depending on the phase-matching condition for
second-harmonic-generation. Moreover, we develop an elemental model which
provides a deep physical insight into the observed dynamics. Despite the
different underlying physical mechanism, the proposed model is remarkably
similar to the description of third-order effects in microresonators, revealing
a potential variety of new effects to be explored and laying the groundwork for
a novel class of highly efficient and versatile frequency comb synthesizers
based on second-order nonlinear materials.


  We consider inflationary cosmology in the context of string compactifications
with multiple throats. In scenarios where the warping differs significantly
between throats, string and Kaluza-Klein physics can generate potentially
observable corrections to the cosmology of inflation and reheating. First we
demonstrate that a very low string scale in the ground state compactification
is incompatible with a high Hubble scale during inflation, and we propose that
the compactification geometry is altered during inflation. In this
configuration, the lowest scale is just above the Hubble scale, which is
compatible with effective field theory but still leads to potentially
observable CMB corrections. Also in the appropriate region of parameter space,
we find that reheating leads to a phase of long open strings in the Standard
Model sector (before the usual radiation-dominated phase). We sketch the
cosmology of the long string phase and we discuss possible observational
consequences.


  We investigate the thermodynamic and transport properties of molybdenum-doped
BaFe2As2 (122) crystals, the first report of hole doping using a 4d element.
The chemical substitution of Mo in place of Fe is possible up to ~ 7%. For
Ba(Fe1-xMox)2As2, the suppression rate of the magnetic transition temperature
with x is the same as in 3d Cr-doped 122 and is independent of the unit cell
changes. This illustrates that temperature-composition phase diagram for
hole-doped 122 can be simply parameterized by x, similar to the electron-doped
122 systems found in literature. Compared to 122 with a coupled
antiferromagnetic order (TN) and orthorhombic structural transition (To) at ~
132 K, 1.3% Mo-doped 122 (x = 0.013) gives TN = To = 125(1) K according to
neutron diffraction results and features in specific heat, magnetic
susceptibility and electrical resistivity. The cell volume expands by ~ 1% with
maximum Mo-doping and TN is reduced to ~ 90 K. There is a new T* feature that
is identified for lightly Cr- or Mo-doped (< 3%) 122 crystals, which is x
dependent. This low-temperature transition may be a trace of superconductivity
or it may have another electronic or magnetic origin.


  Academic performance prediction aims to leverage student-related information
to predict their future academic outcomes, which is beneficial to numerous
educational applications, such as personalized teaching and academic early
warning. In this paper, we address the problem by analyzing students' daily
behavior trajectories, which can be comprehensively tracked with campus
smartcard records. Different from previous studies, we propose a novel
Tri-Branch CNN architecture, which is equipped with row-wise, column-wise, and
depth-wise convolution and attention operations, to capture the characteristics
of persistence, regularity, and temporal distribution of student behavior in an
end-to-end manner, respectively. Also, we cast academic performance prediction
as a top-$k$ ranking problem, and introduce a top-$k$ focused loss to ensure
the accuracy of identifying academically at-risk students. Extensive
experiments were carried out on a large-scale real-world dataset, and we show
that our approach substantially outperforms recently proposed methods for
academic performance prediction. For the sake of reproducibility, our codes
have been released at
https://github.com/ZongJ1111/Academic-Performance-Prediction.


  Attaching a robotic manipulator to a flying base allows for significant
improvements in the reachability and versatility of manipulation tasks. In
order to explore such systems while taking advantage of human capabilities in
terms of perception and cognition, bilateral teleoperation arises as a
reasonable solution. However, since most telemanipulation tasks require visual
feedback in addition to the haptic one, real-time (task-dependent) positioning
of a video camera, which is usually attached to the flying base, becomes an
additional objective to be fulfilled. Since the flying base is part of the
kinematic structure of the robot, if proper care is not taken, moving the video
camera could undesirably disturb the end-effector motion. For that reason, the
necessity of controlling the base position in the null space of the
manipulation task arises. In order to provide the operator with meaningful
information about the limits of the allowed motions in the null space, this
paper presents a novel haptic concept called Null-Space Wall. In addition, a
framework to allow stable bilateral teleoperation of both tasks is presented.
Numerical simulation data confirm that the proposed framework is able to keep
the system passive while allowing the operator to perform time-delayed
telemanipulation and command the base to a task-dependent optimal pose.


  New trigonometric and rational solutions of the quantum Yang-Baxter equation
(QYBE) are obtained by applying some singular gauge transformations to the
known Belavin-Drinfeld elliptic R-matrix for $sl(2,\mathbb{C})$. These
solutions are shown to be related to the standard ones by the quasi-Hopf twist.
We demonstrate that the quantum algebras arising from these new R-matrices can
be obtained as special limits of the Sklyanin algebra. A representation for
these algebras by the difference operators is found. The
$sl(N,\mathbb{C})$-case is discussed.


  Global folds between Banach spaces are obtained from a simple geometric
construction: a Fredholm operator $T$ of index zero with one dimensional kernel
is perturbed by a compatible nonlinear term $P$. The scheme encapsulates most
of the known examples and suggests new ones. Concrete examples rely on the
positivity of an eigenfunction. For the standard Nemitskii case $P(u) = f(u)$
(but $P$ might be nonlocal, non-variational), $T$ might be the Laplacian with
different boundary conditions, as in the Ambrosetti-Prodi theorem, or the
Schr\"{o}dinger operators associated with the quantum harmonic oscillator or
the Hydrogen atom, a spectral fractional Laplacian, a (nonsymmetric) Markov
operator. For self-adjoint operators, we use results on the nondegeneracy of
the ground state. On Banach spaces, a similar role is played by a recent
extension by Zhang of the Krein-Rutman theorem.


  In this work we address the issue of whether the division of clusters in cool
cores (CCs) and non-cool cores (NCCs) is due to a primordial difference or to
how clusters evolve across cosmic time. Our first goal is to establish if
spectra from the central regions of a subclass of NCCs known as cool core
remnants (CCRs) are consistent with having a small but significant amount of
short cooling time gas, thereby allowing a transformation to CC systems on a
timescale of a giga year. Our second goal is to determine if low ionization Fe
lines emitted from this residual cool gas will be detectable by the
calorimeters that will fly on board XRISM and ATHENA. We performed a spectral
analysis of CCR systems with a multi temperature model and, assuming the
different components to be in pressure equilibrium with one another, derived
entropy and cooling time distributions for the X-ray emitting gas. We find that
in most of our systems, the spectral model allows for a fraction of low
entropy, short cooling time gas with a mass that is comparable to the one in CC
systems. Moreover, simulations show that future spectrometers on board XRISM
and ATHENA will have the power to directly resolve emission lines from the low
temperature gas, thereby providing incontrovertible evidence for its presence.
Within the scenario that we have explored, the constant fraction of CCs
measured across cosmic time emerges from a dynamical equilibrium where CCs
transformed in NCCs through mergers are balanced by NCCs that revert to CCs.
Furthermore, CCs and NCCs should not be viewed as distinct sub classes, but as
``states" between which clusters can move.


  We present examples of Pad\'e approximation of the $\alpha$-effect and eddy
viscosity/diffusivity tensors in various flows. Expressions for the tensors
derived in the framework of the standard multiscale formalism are employed.
Algebraically the simplest case is that of a two-dimensional parity-invariant
six-fold rotation-symmetric flow, where eddy viscosity is negative, indicating
intervals of large-scale instability of the flow. Turning to the kinematic
dynamo problem for three-dimensional flows of an incompressible fluid, we
explore application of Pad\'e approximants for computation of tensors of
magnetic $\alpha$-effect and, for parity-invariant flows, of magnetic eddy
diffusivity. We construct Pad\'e approximants of the tensors expanded in power
series in the inverse molecular diffusivity $1/\eta$ around $1/\eta=0$. This
yields the values of the dominant growth rate due to the action of the
$\alpha$-effect or eddy diffusivity to satisfactory accuracy for $\eta$,
several dozen times smaller than the threshold, above which the power series is
convergent. For one sample flow, we observe eddy diffusivity tending to
negative infinity when $\eta$ tends from above to the point of the onset of
small-scale dynamo action in a symmetry-invariant subspace where a neutral
small-scale magnetic mode resides. However, 49 first coefficients in the power
series in $1/\eta$ prove insufficient for Pad\'e approximants to reproduce this
behaviour. We do computations in Fortran in the standard `double' (real*8) and
extended `quadruple' (real*16) precision, as well as perform symbolic
calculations in Mathematica.


  We construct coordinate systems that cover all of the Reissner-Nordstroem
solution with m>|q| and m=|q|, respectively. This is possible by means of
elementary analytical functions. The limit of vanishing charge q provides an
alternative to Kruskal which, to our mind, is more explicit and simpler. The
main tool for finding these global charts is the description of highly
symmetrical metrics by two-dimensional actions. Careful gauge fixing yields
global representatives of the two-dimensional theory that can be rewritten
easily as the corresponding four-dimensional line elements.


  Recently, the thulium atom was cooled down to the Bose-Einstein condensation
temperature, thus opening a pathway to quantum simulation with this atom.
However, successful simulations require instruments to control and readout
states of the atom as well as the ability to control the interaction between
either different species or different states of the same type of species. In
this paper, we provide an experimental demonstration of high-fidelity (over
93%) manipulation of the ground state magnetic sublevels of thulium, which
utilizes a simple and efficient design of a microwave (MW) antenna. The
coherence time and dephasing rate of the energetically highest hyperfine level
of the ground state were also examined.


  We present a systematic analysis of the $B^{(*)}\to\pi\,\ell\,\nu$ weak decay
form factors to order $1/m_b$ in the heavy quark effective theory, including a
discussion of renormalization group effects. These processes are described by a
set of ten universal functions (two at leading order, and eight at order
$1/m_b$), which are defined in terms of matrix elements of operators in the
effective theory. In the soft pion limit, the effective theory yields
normalization conditions for these functions, which generalize the well-known
current algebra relations derived from the combination of heavy quark and
chiral symmetries to next-to-leading order in $1/m_b$. In particular, the
effects of the nearby $B^*$-pole are correctly contained in the form factors of
the effective theory. We discuss the prospects for a model independent
determination of $|V_{ub}|$ and the $B B^*\pi$ coupling constant from these
processes.


  The battery energy storage system (BESS) has immense potential for enhancing
grid reliability and security through its participation in the electricity
market. BESS often seeks various revenue streams by taking part in multiple
markets to unlock its full potential, but effective algorithms for joint-market
participation under price uncertainties are insufficiently explored in the
existing research. To bridge this gap, we develop a novel BESS joint bidding
strategy that utilizes deep reinforcement learning (DRL) to bid in the spot and
contingency frequency control ancillary services (FCAS) markets. Our approach
leverages a transformer-based temporal feature extractor to effectively respond
to price fluctuations in seven markets simultaneously and helps DRL learn the
best BESS bidding strategy in joint-market participation. Additionally, unlike
conventional "black-box" DRL model, our approach is more interpretable and
provides valuable insights into the temporal bidding behavior of BESS in the
dynamic electricity market. We validate our method using realistic market
prices from the Australian National Electricity Market. The results show that
our strategy outperforms benchmarks, including both optimization-based and
other DRL-based strategies, by substantial margins. Our findings further
suggest that effective temporal-aware bidding can significantly increase
profits in the spot and contingency FCAS markets compared to individual market
participation.


  In this article, we study the break-down of smooth and continuous solutions
to isentropic Euler system in multi dimension. Sideris [Comm. Math. Phys. 1985]
proved the blow up of smooth solutions when initial data satisfies an `integral
condition'. We show that a $C^1$ solution of isentropic Euler equation breaks
down if (i) gradient of initial velocity has a negative real eigenvalue at some
point $x_0\in\mathbb{R}^d$ and (ii) Hessian of initial density satisfies a
smallness condition in Sobolev space. Our proof also works for the data which
fails to satisfy the above-mentioned `integral condition'. Furthermore, we
prove the global existence of smooth solution when (i) eigenvalues of gradient
of initial velocity have non-negative real-part and (ii) initial density
satisfies a smallness condition. This extends the global existence result of
[Grassin, Indiana Univ. Math. J. 1998]. Another goal of this article is to
study the breakdown of continuous weak solutions of isentropic Euler equations.
We are able to show that the `integral condition' of Sideris can cause the
breakdown of continuous solutions in finite time. This improves the blow up
result of Sideris from $C^1$ to continuous space.


  The rich and complex data obtained from multi-wavelength observations of
SHB170817A, the short hard gamma ray burst (SHB) associated with GW170817 --the
first neutron stars merger event detected in gravitational waves (GWs)-- are
analyzed in the framework of the cannonball model of SHBs. In this model a
highly relativistic jet is launched by fall back matter on the nascent neutron
star (or black hole) into a surrounding glory (light from the surrounding wind
nebula of the binary neutron stars) which was present already before the
merger. The SHB was produced by inverse Compton scattering of glory photons by
the jet, which was viewed far off-axis. The fading glory, which produced the
initial UVOIR afterglow, was powered by a neutron star remnant. It was
overtaken by a late time X-ray, UVOIR and radio afterglow produced by
synchrotron radiation from the decelerating jet in the interstellar medium of
the host galaxy. If the radio afterglow of SHB170817A was indeed produced by
the jet, it should display a superluminal motion relative to the SHB location,
still detectable in VLA and VLBI radio observations.


  We introduce primitive hyperideals of a hyperring R and show relations with R
itself, and with maximal and prime hyperideals of R. We endow a Jacobson
topology on the set of primitive hyperideals of R and study topological
properties of the corresponding hyperstructure space.


  During the software lifecycle, a program can evolve several times for
different reasons such as the optimisation of a bottle-neck, the refactoring of
an obscure function, etc. These code changes often involve several functions or
modules, so it can be difficult to know whether the correct behaviour of the
previous releases has been preserved in the new release. Most developers rely
on a previously defined test suite to check this behaviour preservation. We
propose here an alternative approach to automatically obtain a test suite that
specifically focusses on comparing the old and new versions of the code. Our
test case generation is directed by a sophisticated combination of several
already existing tools such as TypEr, CutEr, and PropEr; and other ideas such
as allowing the programmer to chose an expression of interest that must
preserve the behaviour, or the recording of the sequences of values to which
this expression is evaluated. All the presented work has been implemented in an
open-source tool that is publicly available on GitHub.


  In this paper, we prove that the Morse index of a multiplicity one, smooth,
min-max minimal hypersurface is generically equal to the dimension of the
homology class detected by the families used in the construction. This confirms
part of the program (\cite{marques-icm}, \cite{marques-neves-cycles},
\cite{marques-neves-index}, \cite{neves-icm}) proposed by the authors with the
goal of developing a Morse theory for the area functional.


  We study skyrmions in the littlest Higgs model and discuss their possible
role as dark matter candidates. Stable massive skyrmions can exist in the
littlest Higgs model also in absence of an exact parity symmetry, since they
carry a conserved topological charge due to the non-trivial third homotopy
group of the SU(5)/SO(5) coset. We find a spherically symmetric skyrmion
solution in this coset. The effects of gauge fields on the skyrmion solutions
are analyzed and found to lead to an upper bound on the skyrmion mass. The
relic abundance is in agreement with the observed dark matter density for
reasonable parameter choices.


  We theoretically investigate the electronic states in monolayer NbSe$_2$ and
develop continuous models to describe these states in Fermi pockets. In
$1H$-type metallic transition-metal dichalcogenides(TMDCs), the Femi surface
consists of three pockets enclosing the $\Gamma$, $K$, and $K'$ points. We
reveal that the conventional effective model used for semiconducting TMDCs is
not sufficient to describe the electronic states in metallic TMDCs and thus
introduce a scheme to construct the effective model from the first-principles
results. All models can be represented by $3\times3$ Hamiltonian and well
reproduce electronic states around the Fermi energy in terms of the orbital
composition and the phase factor. We also show that the $p$ orbitals in
chalcogen atoms, which are ignored in the conventional $2\times2$ model, play a
crucial role in metallic TMDCs. Although the aim of these models is to
reproduce electronic states, they can well describe states near the
high-symmetry points and the profile of Berry curvature in the wave vector
space. The continuous model can be a handleable tool to describe the electronic
states and to analyze the transport phenomena in metallic TMDCs.


  Tidal dwarf galaxies form during the interaction, collision or merger of
massive spiral galaxies. They can resemble "normal" dwarf galaxies in terms of
mass, size, and become dwarf satellites orbiting around their massive
progenitor. They nevertheless keep some signatures from their origin, making
them interesting targets for cosmological studies. In particular, they should
be free from dark matter from a spheroidal halo. Flat rotation curves and high
dynamical masses may then indicate the presence of an unseen component, and
constrain the properties of the "missing baryons", known to exist but not
directly observed. The number of dwarf galaxies in the Universe is another
cosmological problem that can be significantly impacted if tidal dwarf galaxies
formed frequently at high redshift, when the merger rate was high, and many of
them survived until today.


  It has been shown that Information-Disturbance theorem can play an important
role in security proof of quantum cryptography. The theorem is by itself
interesting since it can be regarded as an information theoretic version of
uncertainty principle. It, however, has been able to treat restricted
situations. In this paper, the restriction on the source is abandoned, and a
general information-disturbance theorem is obtained. The theorem relates
information gain by Eve with information gain by Bob.


  The AOMedia Video 1 (AV1) standard can achieve considerable compression
efficiency thanks to the usage of many advanced tools and improvements, such as
advanced inter-prediction modes. However, these come at the cost of high
computational complexity of encoder, which may limit the benefits of the
standard in practical applications. This paper shows that not all sequences
benefit from using all such modes, which indicates that a number of encoder
optimisations can be introduced to speed up AV1 encoding. A method based on
decision trees is proposed to selectively decide whether to test all inter
modes. Appropriate features are extracted and used to perform the decision for
each block. Experimental results show that the proposed method can reduce the
encoding time on average by 43.4\% with limited impact on the coding
efficiency.


  A Stackelberg game is played between a leader and a follower. The leader
first chooses an action, then the follower plays his best response. The goal of
the leader is to pick the action that will maximize his payoff given the
follower's best response. In this paper we present an approach to solving for
the leader's optimal strategy in certain Stackelberg games where the follower's
utility function (and thus the subsequent best response of the follower) is
unknown.
  Stackelberg games capture, for example, the following interaction between a
producer and a consumer. The producer chooses the prices of the goods he
produces, and then a consumer chooses to buy a utility maximizing bundle of
goods. The goal of the seller here is to set prices to maximize his
profit---his revenue, minus the production cost of the purchased bundle. It is
quite natural that the seller in this example should not know the buyer's
utility function. However, he does have access to revealed preference
feedback---he can set prices, and then observe the purchased bundle and his own
profit. We give algorithms for efficiently solving, in terms of both
computational and query complexity, a broad class of Stackelberg games in which
the follower's utility function is unknown, using only "revealed preference"
access to it. This class includes in particular the profit maximization
problem, as well as the optimal tolling problem in nonatomic congestion games,
when the latency functions are unknown. Surprisingly, we are able to solve
these problems even though the optimization problems are non-convex in the
leader's actions.


  2H-NbSe2 is known to be an archetype layered transitional metal
dichalcogenide superconductor with a superconducting transition temperature of
7.3 K.In this article, we investigate the influence of Sn intercalation on
superconducting properties of 2H-NbSe2. Sn being nonmagnetic and having no
outer shell d-electrons unlike transition metals, one naively would presume
that its effect on superconducting properties will be very marginal. However,
our magnetic and transport studies reveal a significant reduction of both
superconducting transition temperature and upper critical field [Tc and BC2
(0)] upon Sn intercalation. With a mere 4 mole% Sn intercalation, it is
observed that Tc and BC2 (0) get suppressed by ~ 3.5 K and 3 T, respectively.
Werthamer-Helfand-Hohenberg (WHH) analysis of magneto-transport data is
performed to estimate BC2 (0). From the low temperature Raman scattering data
in the normal phase of intercalated NbSe2, it is inferred that the suppression
of superconductivity cannot be ascribed to strengthening of charge density wave
(CDW)ordering. The effects such as electron-doping induced Fermi surface change
and/or disorder scattering upon intercalation are speculated to be at play for
the observed phenomena.


  Recent discovery of superconductivity in the twisted bilayer graphene has
stimulated numerous theoretical proposals concerning its exact gap symmetry.
Among them, $d+id$ or $p+ip$-wave were believed to be the most plausible
solutions. Here considering the superconductivity emerges near a correlated
insulating state and may be induced by antiferromagnetic spin fluctuations, we
apply the strong-coupling Eliashberg theory with both inter- and intraband
quantum critical pairing interactions and discuss the possible gap symmetry in
an effective low-energy four-orbital model. Our calculations reveal a nodeless
$s^\pm$-wave as the most probable candidate for superconducting gap symmetry in
the experimentally relevant parameter range. This solution is distinctly
different from previous theoretical proposals. In particular, it contains
interesting topological components in the valley space, which might be tuned by
experimental manipulation of the valley degree of freedom.


  In the post-LEP era the high energy frontier is reachable only by large scale
collaborations and laboratories, while the present lepton colliders operating
at low and intermediate energies are planning major upgrades aimed at
increasing substantially their luminosity, in order to meet the continuous
interest in precision physics. The lowest energies are now represented by
DAPHNE (1.02 GeV cm, operating at Frascati), VEPP-2000 (from 1 to 2 GeV, in
construction at Novosibirsk), CESR (presently operating at Cornell in the range
between 3 to 12 GeV), BEPC (presently operating in Beijing in the range 2 to
5.6 GeV, foreseen luminosity upgrade). A workshop has been held to discuss both
the physics issues and the strategies and problems towards higher luminosities
in the energy range mainly but not only between 1 and 2 GeV. The workshop was
intended to clarify which experiments are more appealing to the physics
community, and which is the way to proceed for obtaining the necessary
luminosity.


  Theoretical arguments and cosmological observations suggest that Einstein's
theory of general relativity needs to be modified at high energies. One of the
best motivated higher-curvature extensions of general relativity is
Einstein-scalar-Gauss-Bonnet gravity, in which a scalar field is coupled to
quadratic curvature invariants. This theory is inspired by an effective
string-theory model and its predictions dramatically differ from Einstein's
theory in high-curvature regions - such as the interior of black holes and the
early universe - where it aims at resolving curvature singularities. In this
work we derive cosmological solutions in Einstein-scalar-Gauss-Bonnet gravity
for quadratic and for exponential coupling functions, and for any spatial
curvature. We discuss already known solutions and find new nonsingular,
inflationary, and bouncing solutions. We study the linear stability of these
solutions and the absence of ghosts, finding that all the aforementioned
solutions are unstable against tensor perturbations. We then introduce a
simple, quadratic potential for the scalar field. In some cases the presence of
a mass term cures the tensor instability. The proposed model is therefore a
viable and attractive candidate for inflation, and one in which the scalar
field is naturally provided by the gravitational sector.


  The force sensor is key to the performance of atomic force microscopy (AFM).
Nowadays, most AFMs use micro-machined force sensors made from silicon, but
piezoelectric quartz sensors are applied at an increasing rate, mainly in
vacuum. These self sensing force sensors allow a relatively easy upgrade of a
scanning tunneling microscope to a combined scanning tunneling/atomic force
microscope. Two fundamentally different types of quartz sensors have achieved
atomic resolution: the 'needle sensor' that is based on a length extensional
resonator and the 'qPlus sensor' that is based on a tuning fork. Here, we
calculate and measure the noise characteristics of these sensors. We find four
noise sources: deflection detector noise, thermal noise, oscillator noise and
thermal drift noise. We calculate the effect of these noise sources as a factor
of sensor stiffness, bandwidth and oscillation amplitude. We find that for self
sensing quartz sensors, the deflection detector noise is independent of sensor
stiffness, while the remaining three noise sources increase strongly with
sensor stiffness. Deflection detector noise increases with bandwidth to the
power of 1.5, while thermal noise and oscillator noise are proportional to the
square root of the bandwidth. Thermal drift noise, however, is inversely
proportional to bandwidth. The first three noise sources are inversely
proportional to amplitude while thermal drift noise is independent of the
amplitude. Thus, we show that the earlier finding that quoted optimal
signal-to-noise ratio for oscillation amplitudes similar to the range of the
forces is still correct when considering all four frequency noise
contributions. Finally, we suggest how the signal-to-noise ratio of the sensors
can be further improved and briefly discuss the challenges of mounting tips.


  The solutions of elliptic problems with a Dirac measure in right-hand side
are not H1 and therefore the convergence of the finite element solutions is
suboptimal. Graded meshes are standard remedy to recover quasi-optimality,
namely optimality up to a log-factor, for low order finite elements in L2-norm.
Optimal (or quasi-optimal for the lowest order case) convergence has been shown
in L2-seminorm, where the L2-seminorm is defined as the L2-norm on a subdomain
which excludes the singularity. Here we show a quasi-optimal convergence for
the Hs-seminorm, s \textgreater{} 0, and an optimal convergence in H1-seminorm
for the lowest order case, on a family of quasi- uniform meshes in dimension 2.
This question is motivated by the use of the Dirac measure as a reduced model
in physical problems, and a high accuracy at the singularity of the finite
element method is not required. Our results are obtained using local Nitsche
and Schatz-type error estimates, a weak version of Aubin-Nitsche duality lemma
and a discrete inf-sup condition. These theoretical results are confirmed by
numerical illustrations.


  While raw images have distinct advantages over sRGB images, e.g., linearity
and fine-grained quantization levels, they are not widely adopted by general
users due to their substantial storage requirements. Very recent studies
propose to compress raw images by designing sampling masks within the pixel
space of the raw image. However, these approaches often leave space for
pursuing more effective image representations and compact metadata. In this
work, we propose a novel framework that learns a compact representation in the
latent space, serving as metadata, in an end-to-end manner. Compared with lossy
image compression, we analyze the intrinsic difference of the raw image
reconstruction task caused by rich information from the sRGB image. Based on
the analysis, a novel backbone design with asymmetric and hybrid spatial
feature resolutions is proposed, which significantly improves the
rate-distortion performance. Besides, we propose a novel design of the context
model, which can better predict the order masks of encoding/decoding based on
both the sRGB image and the masks of already processed features. Benefited from
the better modeling of the correlation between order masks, the already
processed information can be better utilized. Moreover, a novel sRGB-guided
adaptive quantization precision strategy, which dynamically assigns varying
levels of quantization precision to different regions, further enhances the
representation ability of the model. Finally, based on the iterative properties
of the proposed context model, we propose a novel strategy to achieve variable
bit rates using a single model. This strategy allows for the continuous
convergence of a wide range of bit rates. Extensive experimental results
demonstrate that the proposed method can achieve better reconstruction quality
with a smaller metadata size.


  Laser plasma accelerators have the potential to reduce the size of future
linacs for high energy physics by more than an order of magnitude, due to their
high gradient. Research is in progress at current facilities, including the
BELLA PetaWatt laser at LBNL, towards high quality 10 GeV beams and staging of
multiple modules, as well as control of injection and beam quality. The path
towards high-energy physics applications will likely involve hundreds of such
stages, with beam transport, conditioning and focusing. Current research
focuses on addressing physics and R&D challenges required for a detailed
conceptual design of a future collider. Here, the tools used to model these
accelerators and their resource requirements are summarized, both for current
work and to support R&D addressing issues related to collider concepts.


  The purpose of this paper is to study the famous Pappus configuration of $9$
lines and its dual arrangement. We show among others that by applying the
Pappus Theorem to the dual arrangement we obtain the configuration
corresponding to the initial data of beginning configuration. We consider also
the Pappus arrangements with some additional incidences and we establish
algebraic conditions paralleling with these incidences.


  We study the seismic response of idealized 2D cities, constituted by non
equally-spaced, non equally-sized homogenized blocks anchored in a soft layer
overlying a hard half space. The blocks and soft layer are occupied by
dissipative media. To simulate such response, we use an approximation of the
viscoelastic modulus by a low-order rational function of frequency and
incorporate this approximation into a first-order-in-time scheme. Our results
display spatially-variable, strong, long-duration responses inside the blocks
and on the ground, which qualitatively match the responses observed in some
earthquake-prone cities of Mexico, France, the USA, etc.


  The information on a quantum process acquired through measurements plays a
crucial role in the determination of its non-equilibrium thermodynamic
properties. We report on the experimental inference of the stochastic entropy
production rate for a continuously monitored mesoscopic quantum system. We
consider an optomechanical system subjected to continuous displacement Gaussian
measurements and characterise the entropy production rate of the individual
trajectories followed by the system in its stochastic dynamics, employing a
phase-space description in terms of the Wigner entropy. Owing to the specific
regime of our experiment, we are able to single out the informational
contribution to the entropy production arising from conditioning the state on
the measurement outcomes. Our experiment embodies a significant step towards
the demonstration of full-scale control of fundamental thermodynamic processes
at the mesoscopic quantum scale.


  Conversational recommender systems (CRSs) are improving rapidly, according to
the standard recommendation accuracy metrics. However, it is essential to make
sure that these systems are robust in interacting with users including regular
and malicious users who want to attack the system by feeding the system
modified input data. In this paper, we propose an adversarial evaluation scheme
including four scenarios in two categories and automatically generate
adversarial examples to evaluate the robustness of these systems in the face of
different input data. By executing these adversarial examples we can compare
the ability of different conversational recommender systems to satisfy the
user's preferences. We evaluate three CRSs by the proposed adversarial examples
on two datasets. Our results show that none of these systems are robust and
reliable to the adversarial examples.


  We show that the near-brane back-reaction of M2 branes ending on M5 branes
has a rich "spike structure" that is determined by partitioning the numbers of
M2 branes that are terminating on groups of M5 branes. The near-brane limit of
the metric describing these branes has an AdS$_3$ factor, implying the
existence of a dual CFT. Each partition of the M2 and M5 charges among spikes
gives rise to a different "mohawk" revealing a new layer of brane
fractionation. We conjecture that all these mohawks are dual to ground states
of near-brane-intersection CFT's. We show that the supergravity solutions
describing these mohawks are part of the large families of AdS$_3$ $\times S^3
\times S^3$ solutions described in [arXiv:1312.5477]. We identify precisely
which of these families are relevant to brane intersections and show that the
AdS$_3$ invariance emerges from the self-similarity of the spikes.


  The main goal of this article is to study the effect of small, highly
nonlinear, unbounded drifts (small time large deviation principle (LDP) based
on exponential equivalence arguments) for a class of stochastic partial
differential equations (SPDEs) with fully monotone coefficients driven by
multiplicative Gaussian noise. The small time LDP obtained in this paper is
applicable for various quasi-linear and semilinear SPDEs such as porous medium
equations, Cahn-Hilliard equation, 2D Navier-Stokes equations,
convection-diffusion equation, 2D liquid crystal model, power law fluids,
Ladyzhenskaya model, $p$-Laplacian equations, etc., perturbed by multiplicative
Gaussian noise.


  The standard formulation of general relativity fails to describe some recent
interests in the universe. It impels us to go beyond the standard formulation
of gravity. The $f(Q)$ gravity theory is an interesting modified theory of
gravity, where the gravitational interaction is driven by the nonmetricity $Q$.
This study aims to examine the cosmological models with the presence of bulk
viscosity effect in the cosmological fluid within the framework of $f(Q)$
gravity. We construct three bulk viscous fluid models, i.e. (i) for the first
model, we assuming the Lagrangian $f(Q)$ as linear dependence on $Q$, (ii) for
the second model the Lagrangian $f(Q)$ as a polynomial functional form, and
(iii) the Lagrangian $f(Q)$ as a logarithmic dependence on $Q$. Furthermore, we
use 57 points of Hubble data and 1048 Pantheon dataset to constraint the model
parameters. Then, we discuss all the energy conditions for each model, which
helps us to test the self-consistency of our models. Finally, we present the
profiles of the equation of state parameters to test the models' present
status.


  We describe a general approach for maximum a posteriori (MAP) inference in a
class of discrete-continuous factor graphs commonly encountered in robotics
applications. While there are openly available tools providing flexible and
easy-to-use interfaces for specifying and solving inference problems formulated
in terms of either discrete or continuous graphical models, at present, no
similarly general tools exist enabling the same functionality for hybrid
discrete-continuous problems. We aim to address this problem. In particular, we
provide a library, DC-SAM, extending existing tools for inference problems
defined in terms of factor graphs to the setting of discrete-continuous models.
A key contribution of our work is a novel solver for efficiently recovering
approximate solutions to discrete-continuous inference problems. The key
insight to our approach is that while joint inference over continuous and
discrete state spaces is often hard, many commonly encountered
discrete-continuous problems can naturally be split into a "discrete part" and
a "continuous part" that can individually be solved easily. Leveraging this
structure, we optimize discrete and continuous variables in an alternating
fashion. In consequence, our proposed work enables straightforward
representation of and approximate inference in discrete-continuous graphical
models. We also provide a method to approximate the uncertainty in estimates of
both discrete and continuous variables. We demonstrate the versatility of our
approach through its application to distinct robot perception applications,
including robust pose graph optimization, and object-based mapping and
localization.


  We consider biochemical systems associated with a generalised class of Petri
nets with possibly negative token numbers. We show that the existence of a
structural polyhedral Lyapunov function for the biochemical system is
equivalent to the boundedness of the associated Petri net evolution or,
equivalently, to the finiteness of the number of states reachable from each
initial condition. For networks that do not admit a polyhedral Lyapunov
function, we investigate whether it is possible to enforce polyhedral
structural stability by applying a strong negative feedback on some pinned
nodes: in terms of the Petri net, this is equivalent to turning pinned nodes
into black holes that clear any positive or negative incoming token. If such
nodes are chosen so that the transformed Petri net has bounded discrete
trajectories, then there exists a stabilising pinning control: the biochemical
network becomes Lyapunov stable if a sufficiently strong local negative
feedback is applied to the pinned nodes. These results allow us to structurally
identify the critical nodes to be locally controlled so as to ensure the
stability of the whole network.


  The singularity of specific heat ($C_p$) and related properties (viz. thermal
expansion coefficient, compressibility and pressure coefficient) of liquid
$^4He$ at $\lambda-$point is studied and the accuracy of its logarithmic nature
as concluded for the first time from a microscopic theory (cond-mat/0606571) of
a system of interacting bosons is examined. A very good agreement between the
results of this theory and experiments concludes that singularity is
intrinsically logarithmic. However, as shown by other studies, weak effects
arising from earth's gravity and small sample size round it off and $C_p$
assumes asymptotic nature near $T_{\lambda}$.


  Hyperbolic systems on networks often can be written as systems of first order
equations on an interval, coupled by transmission conditions at the endpoints,
also called port-Hamiltonians. However, general results for the latter have
been difficult to interpret in the network language. The aim of this paper is
to derive conditions under which a port-Hamiltonian with general linear
Kirchhoff's boundary conditions can be written as a system of $2\times 2$
hyperbolic equations on a metric graph $\Gamma$. This is achieved by
interpreting the matrix of the boundary conditions as a potential map of vertex
connections of $\Gamma$ and then showing that, under the derived assumptions,
that matrix can be used to determine the adjacency matrix of $\Gamma$.


  We explore the ground-state properties of bosons with dipole-dipole
interactions in a one-dimensional optical lattice. Remarkably, a
crystallization process happens for strong dipolar interactions. Herein, we
provide a detailed characterization and a way to measure the resulting crystal
phase. Using the eigenvalues of the reduced one-body density matrix we define
an order parameter that yields a phase diagram in agreement with an analysis of
the density and two-body density. We demonstrate that the phase diagram can be
detected experimentally using the variance of single-shot measurements.


  Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) is a pair of microsatellites (i.e. GECAM-A and GECAM-B) dedicated to
monitoring gamma-ray transients including gravitational waves high-energy
electromagnetic counterparts, Gamma-ray Bursts, Soft Gamma-ray Repeaters, Solar
Flares and Terrestrial Gamma-ray Flashes. Since launch in December 2020,
GECAM-B has detected hundreds of astronomical and terrestrial events. For these
bursts, localization is the key for burst identification and classification as
well as follow-up observations in multi-wavelength. Here, we propose a Bayesian
localization method with Poisson data with Gaussian background profile
likelihood to localize GECAM bursts based on the burst counts distribution in
detectors with different orientations. We demonstrate that this method can work
well for all kinds of bursts, especially for extremely short ones. In addition,
we propose a new method to estimate the systematic error of localization based
on a confidence level test, which can overcome some problems of the existing
method in literature. We validate this method by Monte Carlo simulations, and
then apply it to a burst sample with accurate location and find that the mean
value of the systematic error of GECAM-B localization is $\sim 2.5^{\circ}$. By
considering this systematic error, we can obtain a reliable localization
probability map for GECAM bursts. Our methods can be applied to other gamma-ray
monitors.


  We consider a general initial state for inflation as the mechanism for
generating scale-dependent hemispherical asymmetry. An observable
scale-dependent non-Gaussianity is generated that leads to observable
hemispherical asymmetry from the super-horizon long mode modulation. We show
that the amplitude of dipole asymmetry falls off exponentially on small angular
scales which can address the absence of dipole asymmetry at these scales.In
addition, depending on the nature of non-vaccum initial state, the amplitude of
the dipole asymmetry has oscillatory features which can be detected in a
careful CMB map analysis. Furthermore, we show that the non-vacuum initial
state provides a natural mechanism for enhancing the super horizon long mode
perturbation as required to generate the dipole asymmetry.


  We study the properties of junctions created by crossing of N identical
branches of linear discrete networks. We reveal that for N>2 such a junction
creates a topological defect and supports two types of spatially localized
modes. We analyze the wave scattering by the junction defect and demonstrate
nonzero reflection for any set of parameters. If the junction is nonlinear, it
is possible to achieve the maximum transmission for any frequency by tuning the
intensity of the scattering wave. In addition, near the maximum transmission
the system shows the bistable behaviour.


  We report on the generation of bulk photocurrents in materials driven by
non-resonant bi-chromatic fields that are circularly polarized and co-rotating.
The nonlinear photocurrents have a fully controllable directionality and
amplitude without requiring carrier-envelope-phase stabilization or few-cycle
pulses, and are generated with photon energies much smaller than the band gap
(reducing heating in the photo-conversion process). We demonstrate with
ab-initio calculations that the photocurrent generation mechanism is universal
and arises in gaped materials (Si, diamond, MgO, hBN), in semi-metals
(graphene), and in two- and three-dimensional systems. Photocurrents are shown
to rely on sub-laser-cycle asymmetries in the nonlinear response that build-up
coherently from cycle-to-cycle as the conduction band is populated.
Importantly, the photocurrents are always transverse to the major axis of the
co-circular lasers regardless of the material's structure and orientation
(analogously to a Hall current), which we find originates from a generalized
time-reversal symmetry in the driven system. At high laser powers (~10^13
W/cm^2) this symmetry can be spontaneously broken by vast electronic
excitations, which is accompanied by an onset of carrier-envelope-phase
sensitivity and ultrafast many-body effects. Our results are directly
applicable for efficient light-driven control of electronics, and for enhancing
sub-band-gap bulk photovoltaic effects.


  We consider the field theories on multiple stacks of D5 branes wrapped on
four cycles of resolved/deformed conifold geometries fibered over a two torus.
The central charges of the D5 branes are slightly misaligned when the branes
are wrapped on various rigid holomorphic two cycles or when they have different
charges with respect to a magnetic flux turned on the two torus. The wrapped D5
branes preserve (0,2) supersymmetry in two dimensions if the Kahler moduli and
the magnetic flux are related. Our geometries are T-dual to the brane
configurations considered by Kutasov-Lin and we provide a geometric
interpretation for their equality between the field theory D-terms and the
magnetic fluxes. We also consider the geometric transitions for rigid
holomorphic two cycles fibered over a two torus with magnetic flux and discuss
the partial breaking of supersymmetry after the geometric transitions.


  Almost 40 years after the discovery of pulsars -- and despite a plethora of
secured data on them -- pulsar theory is still beset by a number of fundamental
inconsistencies. In this short contribution, I will argue that (i) magnetars do
not exist, (ii) (ordinary) pulsars turnoff (or 'die') when their wind pressure
falls short of keeping the CSM at a safe distance, exceeding 10^15 cm,
whereupon they can mimic magnetars, (iii) msec pulsars are born fast (in
core-collapse SNe), and are much older inside globular clusters than outside of
them, (iv) neutron-star corotating magnetospheres can oscillate almost in
resonance with their spin frequency, giving rise to pulse drifting, and to QPOs
of accreting binary X-ray sources, and (v) the dying pulsars are the dominant
sources of the cosmic rays, and of the GRBs.


  We revisit the problem of the two-dimensional spatiotemporal linear stability
of viscoelastic slender jets obeying linear Phan-Thien-Tanner (PTT) stress
constitutive equation, and investigate the role of finite stresses on the
elasto-capilliary stability of the Beads-on-a-String (BOAS) structure
(structures which include the formation of very thin filament between drops)
and identify the regions of topological transition of the advancing jet
interface, in the limit of low to moderate Ohnesorge number ($Oh$) and high
values of Weissenberg number ($We$). The Briggs idea of analytic continuation
\{previously elucidated in the nonaffine response regime [Bansal, Ghosh and
Sircar, ``Spatiotemporal linear stability of viscoelastic free shear flows:
Nonaffine response regime'', Phys. Fluids {\bf 33}, 054106 (2021)]\} is
deployed to classify regions of temporal stability and absolute and convective
instabilities, as well as evanescent modes, and the results are compared with
previously conducted experiments for viscoelastic filaments. The impact of the
finite stresses are evident in the form of strain-hardening ensuing in lower
absolute growth rates, relatively rapid drainage and finite-time pinch-off. The
phase diagrams reveal the influence of (a) capillary force stabilization at
infinitesimally small values of $Oh$, and (b) inertial stabilization at
significantly larger values of $Oh$.


  A nonlinear chain driven by one end may propagate energy in the forbidden
band gap by means of nonlinear modes. For harmonic driving at a given
frequency, the process ocurs at a threshold amplitude by sudden large energy
flow, that we call nonlinear supratransmission. The bifurcation of energy
transmission is demonstrated numerically and experimentally on the chain of
coupled pendula (sine-Gordon and nonlinear Klein-Gordon equations) and
sustained by an extremely simple theory.


  Training large, deep neural networks to convergence can be prohibitively
expensive. As a result, often only a small selection of popular, dense models
are reused across different contexts and tasks. Increasingly, sparsely
activated models, which seek to decouple model size from computation costs, are
becoming an attractive alternative to dense models. Although more efficient in
terms of quality and computation cost, sparse models remain data-hungry and
costly to train from scratch in the large scale regime. In this work, we
propose sparse upcycling -- a simple way to reuse sunk training costs by
initializing a sparsely activated Mixture-of-Experts model from a dense
checkpoint. We show that sparsely upcycled T5 Base, Large, and XL language
models and Vision Transformer Base and Large models, respectively,
significantly outperform their dense counterparts on SuperGLUE and ImageNet,
using only ~50% of the initial dense pretraining sunk cost. The upcycled models
also outperform sparse models trained from scratch on 100% of the initial dense
pretraining computation budget.


  Access patterns to data stored remotely create a side channel that is known
to leak information even if the content of the data is encrypted. To protect
against access pattern leakage, Oblivious RAM is a cryptographic primitive that
obscures the (actual) access trace at the expense of additional access and
periodic shuffling of the server's contents. A class of ORAM solutions, known
as Hierarchical ORAM, has achieved theoretically \emph{optimal} logarithmic
bandwidth overhead. However, to date, Hierarchical ORAMs are seen as only
theoretical artifacts. This is because they require a large number of
communication round-trips to locate (shuffled) elements at the server and
involve complex building blocks such as cuckoo hash tables.
  To address the limitations of Hierarchical ORAM schemes in practice, we
introduce Rank ORAM; the first Hierarchical ORAM that can retrieve data with a
single round-trip of communication (as compared to a logarithmic number in
previous work). To support non-interactive communication, we introduce a
\emph{compressed} client-side data structure that stores, implicitly, the
location of each element at the server. In addition, this location metadata
enables a simple protocol design that dispenses with the need for complex
cuckoo hash tables.
  Rank ORAM requires asymptotically smaller memory than existing
(non-Hierarchical) state-of-the-art practical ORAM schemes (e.g., Ring ORAM)
while maintaining comparable bandwidth performance. Our experiments on real
network file-system traces demonstrate a reduction in client memory, against
existing approaches, of a factor of~$100$. For example, when {outsourcing} a
database of $17.5$TB, required client-memory is only $290$MB vs. $40$GB for
standard approaches.


  Recently, it was demonstrated that a graphene/dielectric/metal configuration
can support acoustic plasmons, which exhibit extreme plasmon confinement an
order of magnitude higher than that of conventional graphene plasmons. Here, we
investigate acoustic plasmons supported in a monolayer and multilayers of black
phosphorus (BP) placed just a few nanometers above a conducting plate. In the
presence of a conducting plate, the acoustic plasmon dispersion for the
armchair direction is found to exhibit the characteristic linear scaling in the
mid- and far-infrared regime while it largely deviates from that in the long
wavelength limit and near-infrared regime. For the zigzag direction, such
scaling behavior is not evident due to relatively tighter plasmon confinement.
Further, we demonstrate a new design for an acoustic plasmon resonator that
exhibits higher plasmon confinement and resonance efficiency than BP ribbon
resonators in the mid-infrared and longer wavelength regime. Theoretical
framework and new resonator design studied here provide a practical route
toward the experimental verification of the acoustic plasmons in BP and open up
the possibility to develop novel plasmonic and optoelectronic devices that can
leverage its strong in-plane anisotropy and thickness-dependent band gap.


  Crystalline etalons present several advantages with respect to other types of
filtergraphs when employed in magnetographs. Specially that they can be tuned
by only applying electric fields. However, anisotropic crystalline etalons can
also introduce undesired birefringent effects that corrupt the polarization of
the incoming light. In particular, uniaxial Fabry-P\'erots, such as LiNbO3
etalons, are birefringent when illuminated with an oblique beam. The farther
the incidence from the normal, the larger the induced retardance between the
two orthogonal polarization states. The application of high-voltages, as well
as fabrication defects, can also change the direction of the optical axis of
the crystal, introducing birefringence even at normal illumination. Here we
obtain analytical expressions for the induced retardance and for the Mueller
matrix of uniaxial etalons located in both collimated and telecentric
configurations. We also evaluate the polarimetric behavior of Z-cut crystalline
etalons with the incident angle, with the orientation of the optical axis, and
with the f-number of the incident beam for the telecentric case. We study
artificial signals produced in the output Stokes vector in the two
configurations. Last, we discuss the polarimetric dependence of the imaging
response of the etalon for both collimated and telecentric setups.


  A path is a simple, piecewise linear curve made up of alternating horizontal
and vertical line segments in the plane. A $k$-bend path is a path made up of
at most $k + 1$ line segments. A $B_k$-VPG representation of a graph is a
collection of $k$-bend paths such that each path in the collection represents a
vertex of the graph and two such paths intersect if and only if the vertices
they represent are adjacent in the graph. The graphs that have a $B_k$-VPG
representation are called $B_k$-VPG graphs. It is known that the poset
dimension $dim(G)$ of a cocomparability graph $G$ is greater than or equal to
its bend number $bend(G)$. Cohen et al. ({\textsc{order 2015}}) asked for
examples of cocomparability graphs with low bend number and high poset
dimension. We answer this question by proving that for each $m, t \in
\mathbb{N}$, there exists a cocomparability graph $G_{t,m}$ with $t <
bend(G_{t,m}) \leq 4t+29$ and $dim(G_{t,m})-bend(G_{t,m})>m$. Techniques used
to prove the above result, allows us to partially address the open question
posed by Chaplick et al. ({\textsc{wg 2012}}) who asked whether
$B_k$-VPG-chordal $\subsetneq$ $B_{k+1}$-VPG-chordal for all $k \in
\mathbb{N}$. We address this by proving that there are infinitely many $m \in
\mathbb{N}$ such that $B_m$-VPG-split $\subsetneq$ $B_{m+1}$-VPG-split which
provides infinitely many positive examples. We use the same techniques to prove
that, for all $t \in \mathbb{N}$, $B_t$-VPG-$Forb(C_{\geq 5})$ $\subsetneq$
$B_{4t+29}$-VPG-$Forb(C_{\geq 5})$, where $Forb(C_{\geq 5})$ denotes the family
of graphs that does not contain induced cycles of length greater than 4.
Furthermore, we show that for all $t \in \mathbb{N}$, $PB_t$-VPG-split
$\subsetneq PB_{36t+80}$-VPG-split, where $PB_t$-VPG denotes the class of
graphs with proper bend number at most $t$.


  Observations of very-high-energy (VHE) gamma-ray emission from supernova
remnants (SNR) established them as sources of accelerated particles up to
energies of 100 TeV. The dominant process - leptonic or hadronic - responsible
for the VHE emission is still not proven for most of the SNRs.
  Molecular clouds (MCs) in the vicinity of SNRs provide increased amount of
target material for accelerated particles escaping the SNRs, thus making MCs
potential gamma-ray sources. The predicted gamma-ray flux for MCs offset from
the SNR shock depends on the applied diffusion model for VHE particles and the
SNR and MC properties, which encounter large uncertainties. While the the
average galactic diffusion coefficient is estimated, the spatially resolved
propagation properties of VHE cosmic rays are unknown. gamma-ray emitting MCs
provide a unique possibility to derive new information on the propagation of
VHE particles through the ISM and on the acceleration of hadrons at SNRs.
  We present in this paper a strategy and first results of a systematic search
for TeV gamma-ray emitting MCs in the vicinity of SNRs in the galactic plane
region. Based on a theoretical model and current SNR and MC catalogues the
detectable parameter space (e.g. diffusion coefficient, SNR age) for current
Imaging Atmospheric Cherenkov Telescope systems (IACTs) is obtained. This
allows to identify potential gamma-ray emitting regions.


  An oscillator is called isochronous if all motions have a common period. When
the system is forced by a time-dependent perturbation with the same period the
phenomenon of resonance may appear. We give a sufficient condition on the
perturbation in order that resonance occurs when the period annulus of the
isochronous oscillator is bounded. In this context, resonance means that all
solutions escape from the period annulus.


  Radio astrometry of nearby, low-mass stars has the potential to be a powerful
tool for the discovery and characterization of planetary companions. We present
a Very Large Array survey of 172 active M dwarfs at distances of less than 10
pc. Twenty nine stars were detected with flux densities greater than 100
microJy. We observed 7 of these stars with the Very Long Baseline Array at
milliarcsecond resolution in three separate epochs. With a detection threshold
of 500 microJy in images of sensitivity 1 sigma ~ 100 microJy, we detected
three stars three times (GJ 65B, GJ896A, GJ 4247), one star twice (GJ 285), and
one star once (GJ 803). Two stars were undetected (GJ 412B and GJ 1224). For
the four stars detected in multiple epochs, residuals from the
optically-determined proper motions have an rms deviation of ~0.2
milliarcseconds, consistent with statistical noise limits. Combined with
previous optical astrometry, these residuals provide acceleration upper limits
that allow us to exclude planetary companions more massive than 3-6 M_Jup at a
distance of ~1 AU with a 99% confidence level.


  {\sl Ground Level Enhancement (GLE)} events represent the largest class of
{\sl solar energetic particle (SEP)} events that require acceleration processes
to produce $\gapprox 1$ GeV ions in order to produce showers of secondary
particles in the Earth's atmosphere with sufficient intensity to be detected by
ground-level neutron monitors, above the background of cosmics rays. Although
the association of GLE events with both solar flares and coronal mass ejections
(CMEs) is undisputed, the question arises about the location of the responsible
acceleration site: coronal flare sites or heliospheric CME-associated shocks?
To investigate the first possibility we explore the timing of GLE events with
respect to hard X-ray production in solar flares, considering the height and
magnetic topology of flares, the role of extended acceleration, and particle
trapping. We find that 50% (6 out of 12) of recent (non-occulted) GLE events
are accelerated during the impulsive flare phase, while the remaining half are
accelerated significantly later. It appears that the prompt GLE component,
which is observed in virtually all GLE events, is caused by flare-accelerated
particles in the lower corona, while the delayed gradual GLE component can be
produced by both, either by extended acceleration and/or trapping in flare
sites, or by particles accelerated in CME-associated shocks during their
propagation through the heliosphere.


  We investigate the existence of multiple bound state solutions, in particular
sign-changing solutions. By using the method of invariant sets of descending
flow, we prove that this system has infinitely many sign-changing solutions. In
particular, the nonlinear term includes the power-type nonlinearity
$f(u)=|u|^{p-2}u$ for the well-studied case $p\in(4,6)$, and the less-studied
case $p\in(3,4)$, and for the latter case few existence results are available
in the literature.


  The sufficient condition for partial function from the cartesian square of
the finite set to the reals to be compatible with some metric on this set is
given. It is then shown, that when afforementioned set and function are
respectively a space of binary words of length n and probalities of receiving
some word after sending the other word through Binary Assymetric Channel the
condition is satisfied so the required metrics exist.


  Galaxy surveys probe both structure formation and the expansion rate, making
them promising avenues for understanding the dark universe. Photometric surveys
accurately map the 2D distribution of galaxy positions and shapes in a given
redshift range, while spectroscopic surveys provide sparser 3D maps of the
galaxy distribution. We present a way to analyse overlapping 2D and 3D maps
jointly and without loss of information. We represent 3D maps using spherical
Fourier-Bessel (sFB) modes, which preserve radial coverage while accounting for
the spherical sky geometry, and we decompose 2D maps in a spherical harmonic
basis. In these bases, a simple expression exists for the cross-correlation of
the two fields. One very powerful application is the ability to simultaneously
constrain the redshift distribution of the photometric sample, the sample
biases, and cosmological parameters. We use our framework to show that combined
analysis of DESI and LSST can improve cosmological constraints by factors of
${\sim}1.2$ to ${\sim}1.8$ on the region where they overlap relative to
identically sized disjoint regions. We also show that in the overlap of DES and
SDSS-III in Stripe 82, cross-correlating improves photo-$z$ parameter
constraints by factors of ${\sim}2$ to ${\sim}12$ over internal photo-$z$
reconstructions.


  We investigate quantum phase transitions occurring in a system of strongly
interacting ultracold bosons in a 1D optical lattice. After discussing the
commensurate-incommensurate transition, we focus on the phases appearing at
incommensurate filling. We find a rich phase diagram, with superfluid,
supersolid and solid (kink-lattice) phases. Supersolids generally appear in
theoretical studies of systems with long-range interactions; our results break
this paradigm and show that they may also emerge in models including only
short-range (contact) interactions, provided that quantum fluctuations are
properly taken into account.


  We construct twisted Calogero-Moser (CM) systems with spins as the Hitchin
systems derived from the Higgs bundles over elliptic curves, where transitions
operators are defined by an arbitrary finite order automorphisms of the
underlying Lie algebras. In this way we obtain the spin generalization of the
twisted D'Hoker- Phong and Bordner-Corrigan-Sasaki-Takasaki systems. As by
product, we construct the corresponding twisted classical dynamical r-matrices
and Knizhnik-Zamolodchikov-Bernard equations related to the automorphisms of
the Lie algebras.


  Abstract Generative adversarial networks (GANs) have achieved impressive
performance in data synthesis and have driven the development of many
applications. However, GANs are known to be hard to train due to their bilevel
objective, which leads to the problems of convergence, mode collapse, and
gradient vanishing. In this paper, we propose a new generative model called the
generative adversarial NTK (GA-NTK) that has a single-level objective. The
GA-NTK keeps the spirit of adversarial learning (which helps generate plausible
data) while avoiding the training difficulties of GANs. This is done by
modeling the discriminator as a Gaussian process with a neural tangent kernel
(NTK-GP) whose training dynamics can be completely described by a closed-form
formula. We analyze the convergence behavior of GA-NTK trained by gradient
descent and give some sufficient conditions for convergence. We also conduct
extensive experiments to study the advantages and limitations of GA-NTK and
propose some techniques that make GA-NTK more practical.


  In this paper, we present two control laws that are tailored for control
applications in which computational and/or communication resources are scarce.
Namely, we consider minimum attention control, where the `attention' that a
control task requires is minimised given certain performance requirements, and
anytime attention control, where the performance under the `attention' given by
a scheduler is maximised. Here, we interpret `attention' as the inverse of the
time elapsed between two consecutive executions of a control task. By focussing
on linear plants, by allowing for only a finite number of possible intervals
between two subsequent executions of the control task, by making a novel
extension to the notion of control Lyapunov functions and taking these novel
extended control Lyapunov function to be infinity-norm-based, we can formulate
the aforementioned control problems as online linear programs, which can be
solved efficiently. Furthermore, we provide techniques to construct suitable
infinity-norm-based extended control Lyapunov functions for our purposes.
Finally, we illustrate the resulting control laws using numerical examples. In
particular, we show that minimum attention control outperforms an alternative
implementation-aware control law available in the literature.


  Let $L_1$ be a nonnegative self-adjoint operator in $L^2({\mathbb R}^n)$
satisfying the Davies-Gaffney estimates and $L_2$ a second order divergence
form elliptic operator with complex bounded measurable coefficients. A typical
example of $L_1$ is the Schr\"odinger operator $-\Delta+V$, where $\Delta$ is
the Laplace operator on ${\mathbb R}^n$ and $0\le V\in
L^1_{\mathop\mathrm{loc}} ({\mathbb R}^n)$. Let $H^p_{L_i}(\mathbb{R}^n)$ be
the Hardy space associated to $L_i$ for $i\in\{1,\,2\}$. In this paper, the
authors prove that the Riesz transform $D (L_i^{-1/2})$ is bounded from
$H^p_{L_i}(\mathbb{R}^n)$ to the classical weak Hardy space
$WH^p(\mathbb{R}^n)$ in the critical case that $p=n/(n+1)$. Recall that it is
known that $D (L_i^{-1/2})$ is bounded from $H^p_{L_i}(\mathbb{R}^n)$ to the
classical Hardy space $H^p(\mathbb{R}^n)$ when $p\in(n/(n+1),\,1]$.


  We propose a dynamic edge exchangeable network model that can capture sparse
connections observed in real temporal networks, in contrast to existing models
which are dense. The model achieved superior link prediction accuracy on
multiple data sets when compared to a dynamic variant of the blockmodel, and is
able to extract interpretable time-varying community structures from the data.
In addition to sparsity, the model accounts for the effect of social influence
on vertices' future behaviours. Compared to the dynamic blockmodels, our model
has a smaller latent space. The compact latent space requires a smaller number
of parameters to be estimated in variational inference and results in a
computationally friendly inference algorithm.


  This paper studies the problem of model training under Federated Learning
when clients exhibit cluster structure. We contextualize this problem in mixed
regression, where each client has limited local data generated from one of $k$
unknown regression models. We design an algorithm that achieves global
convergence from any initialization, and works even when local data volume is
highly unbalanced -- there could exist clients that contain $O(1)$ data points
only. Our algorithm first runs moment descent on a few anchor clients (each
with $\tilde{\Omega}(k)$ data points) to obtain coarse model estimates. Then
each client alternately estimates its cluster labels and refines the model
estimates based on FedAvg or FedProx. A key innovation in our analysis is a
uniform estimate on the clustering errors, which we prove by bounding the VC
dimension of general polynomial concept classes based on the theory of
algebraic geometry.


  In this work we explore the effects of adopting initial mass functions (IMFs)
variable in time on the chemical evolution of the Galaxy. In order to do that
we adopt a chemical evolution model which assumes two main infall episodes for
the formation of the Galaxy and which proved to be successful in reproducing
the majority of the observational constraints, at least for the case of a
constant IMF. Different variable IMFs are tested with this model, all assuming
that massive stars are preferentially formed in ambients of low metallicity.
This implies that massive stars are formed preferentially at early times and at
large galactocentric distances. Our numerical results have shown that all the
variable IMFs proposed so far are unable to reproduce all the relevant
observational constraints in the Galaxy and that a constant IMF still
reproduces better the observations. In particular, variable IMFs of the kind
explored here are unable to reproduce the observed abundance gradients even
when allowing for changes in other chemical evolution model parameters as, for
instance, the star formation rate. As a consequence of this we conclude that
the G-dwarf metallicity distribution is best explained by infall with a large
timescale and a constant IMF, since it is possible to find variable IMFs of the
kind studied here, reproducing the G-dwarf metallicity but this worsen the
agreement with other observational constraints.


  We present a refined treatment of H, He I, and He II recombination in the
early Universe. The difference from previous calculations is that we use
multi-level atoms and evolve the population of each level with redshift by
including all bound-bound and bound-free transitions. In this framework we
follow several hundred atomic energy levels for H, He I, and He II combined.
The main improvements of this method over previous recombination calculations
are: (1) allowing excited atomic level populations to depart from an
equilibrium distribution; (2) replacing the total recombination coefficient
with recombination to and photoionization from each level directly at each
redshift step; and (3) correct treatment of the He I atom, including the
triplet and singlet states. We find that the ionization fraction x_e = n_e/n_H
is approximately 10% smaller at redshifts <~800 than in previous calculations,
due to the non-equilibrium of the excited states of H, which is caused by the
strong but cool radiation field at those redshifts. In addition we find that He
I recombination is delayed compared with previous calculations, and occurs only
just before H recombination. These changes in turn can affect the predicted
power spectrum of microwave anisotropies at the few percent level. Other
improvements such as including molecular and ionic species of H, including
complete heating and cooling terms for the evolution of the matter temperature,
including collisional rates, and including feedback of the secondary spectral
distortions on the radiation field, produce negligible change to x_e. The lower
x_e at low z found in this work affects the abundances of H molecular and ionic
species by 10-25%. However this difference is probably not larger than other
uncertainties in the reaction rates.


  Machine Learning models are vulnerable to adversarial attacks that rely on
perturbing the input data. This work proposes a novel strategy using
Autoencoder Deep Neural Networks to defend a machine learning model against two
gradient-based attacks: The Fast Gradient Sign attack and Fast Gradient attack.
First we use an autoencoder to denoise the test data, which is trained with
both clean and corrupted data. Then, we reduce the dimension of the denoised
data using the hidden layer representation of another autoencoder. We perform
this experiment for multiple values of the bound of adversarial perturbations,
and consider different numbers of reduced dimensions. When the test data is
preprocessed using this cascaded pipeline, the tested deep neural network
classifier yields a much higher accuracy, thus mitigating the effect of the
adversarial perturbation.


  This work reports aspect related to chemical capping synthesis of nano-sized
particles of nickel oxide. It is a simple, novel and cost effective method. The
average particle size, specific surface area, crystallinity index are estimated
from XRD analysis. The structural, functional groups and optical characters are
analyzed with using of SEM, FTIR and UV- visible techniques. XRD studies
confirm the presence of high degree of crystallinity nature of nickel oxide
nanoparticles. Their particle size is found to be 12 nm and specific surface
area (SSA) is 74m2 g-1. The optical band gap energy value 3.83ev has also been
determined from UV-vis spectrum.


  We present Gemini-S/GMOS-IFU optical spectroscopy of four regions near the
centre of the nearby (3.8 Mpc) dwarf starburst galaxy NGC 5253. This galaxy is
famous for hosting a radio supernebula containing two deeply embedded massive
super star clusters, surrounded by a region of enhanced nitrogen abundance that
has been linked to the presence of WR stars. We detected 11 distinct sources of
red WR bump (CIV) emission over a 20" (~350 pc) area, each consistent with the
presence of ~1 WCE-type star. WC stars are not found coincident with the
supernebula, although WN stars have previously been detected here. We performed
a multi-component decomposition of the H\alpha\ line across all four fields and
mapped the kinematics of the narrow and broad (FWHM = 100-250 km/s) components.
These maps paint a picture of localised gas flows, as part of multiple
overlapping bubbles and filaments driven by the star clusters throughout the
starburst. We confirm the presence of a strong H\alpha\ velocity gradient over
~4.5" (~80 pc) coincident with the region of N/O enhancement, and high gas
density known from previous study, and interpret this as an accelerating
ionized gas outflow from the supernebula clusters. We measure the ionized gas
abundances in a number of regions in the outer IFU positions and combine these
with measurements from the literature to assess the radial abundance
distribution. We find that the O/H and N/H profiles are consistent with being
flat. Only the central 50 pc exhibits the well-known N/O enhancement, and we
propose that the unusually high densities/pressures in the supernebula region
have acted to impede the escape of metal-enriched hot winds from the star
clusters and allow them to mix with the cooler phases, thus allowing these
freshly processed chemicals to be seen in the optical.


  Real-time collaborative editing in computational notebooks can improve the
efficiency of teamwork for data scientists. However, working together through
synchronous editing of notebooks introduces new challenges. Data scientists may
inadvertently interfere with each others' work by altering the shared codebase
and runtime state if they do not set up a social protocol for working together
and monitoring their collaborators' progress. In this paper, we propose a
real-time collaborative editing model for resolving conflict edits in
computational notebooks that introduces three levels of edit protection to help
collaborators avoid introducing errors to both the program source code and
changes to the runtime state.


  The site frequency spectrum (SFS) is a popular summary statistic of genomic
data. While the SFS of a constant-sized population undergoing neutral mutations
has been extensively studied in population genetics, the rapidly growing amount
of cancer genomic data has attracted interest in the spectrum of an
exponentially growing population. Recent theoretical results have generally
dealt with special or limiting cases, such as considering only cells with an
infinite line of descent, assuming deterministic tumor growth, or taking
large-time or large-population limits. In this work, we derive exact
expressions for the expected SFS of a cell population that evolves according to
a stochastic branching process, first for cells with an infinite line of
descent and then for the total population, evaluated either at a fixed time
(fixed-time spectrum) or at the stochastic time at which the population reaches
a certain size (fixed-size spectrum). We find that while the rate of mutation
scales the SFS of the total population linearly, the rates of cell birth and
cell death change the shape of the spectrum at the small-frequency end,
inducing a transition between a $1/j^2$ power-law spectrum and a $1/j$ spectrum
as cell viability decreases. We show that this insight can in principle be used
to estimate the ratio between the rate of cell death and cell birth, as well as
the mutation rate, using the site frequency spectrum alone. Although the
discussion is framed in terms of tumor dynamics, our results apply to any
exponentially growing population of individuals undergoing neutral mutations.


  We show how to efficiently send an M-partite entangled state along a spin
chain of arbitrary size. Specifically, we show how an entangled M-partite W
sate can be almost flawlessly transmitted from one end (Alice) to the other end
(Bob) of a spin-1/2 chain described by a slightly modified XX model. We achieve
an almost perfect transmission without employing external magnetic fields or
modulating the coupling constants among the spins of the chain, the two
standard approaches used to achieve a good transmission efficiency. Moreover,
the protocol here proposed can be used to transform an M-partite W state with
Alice into an M'-partite one with Bob (M different from M'). We also
investigate the proposed protocol's response to several types of disorder and
noise and show that it is quite robust to small deviations about the coupling
constants of the optimal ordered and noiseless case.


  We consider the problem of online learning in the linear contextual bandits
setting, but in which there are also strong individual fairness constraints
governed by an unknown similarity metric. These constraints demand that we
select similar actions or individuals with approximately equal probability
(arXiv:1104.3913), which may be at odds with optimizing reward, thus modeling
settings where profit and social policy are in tension. We assume we learn
about an unknown Mahalanobis similarity metric from only weak feedback that
identifies fairness violations, but does not quantify their extent. This is
intended to represent the interventions of a regulator who "knows unfairness
when he sees it" but nevertheless cannot enunciate a quantitative fairness
metric over individuals. Our main result is an algorithm in the adversarial
context setting that has a number of fairness violations that depends only
logarithmically on $T$, while obtaining an optimal $O(\sqrt{T})$ regret bound
to the best fair policy.


  The prominence of deep learning, large amount of annotated data and
increasingly powerful hardware made it possible to reach remarkable performance
for supervised classification tasks, in many cases saturating the training
sets. However the resulting models are specialized to a single very specific
task and domain. Adapting the learned classification to new domains is a hard
problem due to at least three reasons: (1) the new domains and the tasks might
be drastically different; (2) there might be very limited amount of annotated
data on the new domain and (3) full training of a new model for each new task
is prohibitive in terms of computation and memory, due to the sheer number of
parameters of deep CNNs. In this paper, we present a method to learn
new-domains and tasks incrementally, building on prior knowledge from already
learned tasks and without catastrophic forgetting. We do so by jointly
parametrizing weights across layers using low-rank Tucker structure. The core
is task agnostic while a set of task specific factors are learnt on each new
domain. We show that leveraging tensor structure enables better performance
than simply using matrix operations. Joint tensor modelling also naturally
leverages correlations across different layers. Compared with previous methods
which have focused on adapting each layer separately, our approach results in
more compact representations for each new task/domain. We apply the proposed
method to the 10 datasets of the Visual Decathlon Challenge and show that our
method offers on average about 7.5x reduction in number of parameters and
competitive performance in terms of both classification accuracy and Decathlon
score.


  Given a surface S in P^3 and a collection of general points on it, how many
surfaces of a given degree intersect S in a curve with prescribed
multiplicities at the points? We formulate two natural conjectures which would
answer this question, and we show they are equivalent. We then prove these
conjectures in case all multiplicities are small.


  We present the first quantitative experimental evidence for the underscreened
Kondo effect, an uncomplete compensation of a quantized magnetic moment by
conduction electrons, as originally proposed by Nozieres and Blandin. The
device consists of an even charge spin S = 1 molecular quantum dot, obtained by
electromigration of C60 molecules into gold nanogaps and operated in a dilution
fridge. The persistence of logarithmic singularities in the low temperature
conductance is demonstrated by a comparison to the fully screened configuration
obtained in odd charge spin S = 1/2 Coulomb diamonds. We also discover an
extreme sensitivity of the underscreened Kondo resonance to magnetic field,
that we confirm on the basis of numerical renormalization group calculations.


  We consider a large class of optical cavities and gain media with an off-axis
external feedback which introduces a two-point nonlocality. This nonlocality
moves the lasing threshold and opens large windows of control parameters where
weak light spots can be strongly amplified while the background radiation
remains very low. Furthermore, transverse phase and group velocities of a
signal can be independently tuned and this enables to steer it non
mechanically, to control its spatial chirping and to split it into two
counter-propagating ones.


  Using the $\ell_1$-norm to regularize the estimation of the parameter vector
of a linear model leads to an unstable estimator when covariates are highly
correlated. In this paper, we introduce a new penalty function which takes into
account the correlation of the design matrix to stabilize the estimation. This
norm, called the trace Lasso, uses the trace norm, which is a convex surrogate
of the rank, of the selected covariates as the criterion of model complexity.
We analyze the properties of our norm, describe an optimization algorithm based
on reweighted least-squares, and illustrate the behavior of this norm on
synthetic data, showing that it is more adapted to strong correlations than
competing methods such as the elastic net.


  We consider a binary Lennard-Jones glassformer whose super-Arrhenius dynamics
are correlated with the formation of icosahedral structures. Upon cooling these
icosahedra organize into mesoclusters. We recast this glassformer as an
effective system of icosahedra which we describe with a population dynamics
model. This model we parameterize with data from the temperature regime
accessible to molecular dynamics simulations. We then use the model to
determine the population of icosahedra in mesoclusters at arbitrary
temperature. Using simulation data to incorporate dynamics into the model we
predict relaxation behavior at temperatures inaccessible to conventional
approaches. Our model predicts super-Arrhenius dynamics whose relaxation time
remains finite for non-zero temperature.


  The $O(v^2)$ relativistic correction for inelastic $J/\psi$ photoproduction,
in which heavy quark pairs are in the dominant Fock state of the quarkonium, is
studied in the framework of NRQCD factorization. An assessment of its
significance, particularly in comparison to the color octet contributions, is
made. It is found that the impact on the energy distribution is negative in
certain regions of phase space. The predictions are compared with
photoproduction data from DESY-HERA.


  In this paper we first construct natural filtrations on the full theta lifts
for any real reductive dual pairs. We will use these filtrations to calculate
the associated cycles and therefore the associated varieties of Harish-Chandra
modules of the indefinite orthogonal groups which are theta lifts of unitary
lowest weight modules of the metaplectic double covers of the real symplectic
groups. We will show that some of these representations are special unipotent
and satisfy a K-type formula in a conjecture of Vogan.