cssi/SciSciGPT-SciSciNet huggingface dataset:
Associating ridesourcing with road safety outcomes: Insights from Austin, Texas.

Improving road safety and setting targets for reducing traffic-related crashes and deaths are highlighted as part of the United Nation's sustainable development goals and vision zero efforts around the globe. The advent of transportation network companies, such as ridesourcing, expands mobility options in cities and may impact road safety outcomes. In this study, we analyze the effects of ridesourcing use on road crashes, injuries, fatalities, and driving while intoxicated (DWI) offenses in Travis County Texas. Our approach leverages real-time ridesourcing volume to explain variation in road safety outcomes. Spatial panel data models with fixed effects are deployed to examine whether the use of ridesourcing is significantly associated with road crashes and other safety metrics. Our results suggest that for a 10% increase in ridesourcing trips, we expect a 0.12% decrease in road crashes (p<0.05), a 0.25% decrease in road injuries (p<0.001), and a 0.36% decrease in DWI offenses (p<0.0001) in Travis County. Ridesourcing use is not associated with road fatalities at a 0.05 significance level. This study augments existing work because it moves beyond binary indicators of ridesourcing presence or absence and analyzes patterns within an urbanized area rather than metropolitan-level variation. Contributions include developing a data-rich approach for assessing the impacts of ridesourcing use on our transportation system's safety, which may serve as a template for future analyses of other US cities. Our findings provide feedback to policymakers by clarifying associations between ridesourcing use and traffic safety, while helping identify sets of actions to achieve safer and more efficient shared mobility systems.
THE UV POLARIZATION OF X-RAY BINARY SYSTEMS OBSERVED WITH THE HUBBLE SPACE TELESCOPE

The High-Speed Photometer (HSP) was one of the four axial instruments on the Hubble Space Telescope (HST) from April, 1990 to December, 1993. We used this instrument to observe the X-ray binary systems HD 153919, Vela XR-1 and Cyg XR-1 both photometrically and polarimetrically in the UV. The photometric and polarimetric light curves of each target have been constructed by measuring the flux and linear polarization in several wavelength bands, at several different phases within one binary orbit. The results obtained from the UV polarimetric observations provide strong evidence for Rayleigh (recombined material) scattering from gas streams and stellar wind in these systems. The amplitude of polarimetric variability increases significantly in the UV, for all three systems. The UV polarimetric light curves obtained for Vela XR-1 and HD 153919 show an added component of linear polarization present at first quadrature, inconsistent with the standards model of Brown et al. (1978). However, the UV polarimetric light curves obtained for Cyg XR-1 are well-represented by the standard model. There was also evidence for changes in the circumbinary scattering structure from one orbit to the next, in Cyg XR-1 and Vela XR-1. In addition to these results, we derived estimates for the orbital inclination, location of the scattering structure relative to the line of centers, and orientation of the orbital angular momentum for the system (and associated confidence intervals for each parameter). These results were compared to previously published ground based observations.
Near-Optimal Coresets of Kernel Density Estimates

We construct near-optimal coresets for kernel density estimates for points in $${\mathbb {R}}^d$$ when the kernel is positive definite. Specifically we provide a polynomial time construction for a coreset of size $$O(\sqrt{d}/\varepsilon \cdot \sqrt{\log 1/\varepsilon } )$$ , and we show a near-matching lower bound of size $$\Omega (\min \{\sqrt{d}/\varepsilon , 1/\varepsilon ^2\})$$ . When $$d\ge 1/\varepsilon ^2$$ , it is known that the size of coreset can be $$O(1/\varepsilon ^2)$$ . The upper bound is a polynomial-in- $$(1/\varepsilon )$$ improvement when $$d \in [3,1/\varepsilon ^2)$$ and the lower bound is the first known lower bound to depend on d for this problem. Moreover, the upper bound restriction that the kernel is positive definite is significant in that it applies to a wide variety of kernels, specifically those most important for machine learning. This includes kernels for information distances and the sinc kernel which can be negative.
Development of a covalent inhibitor of gut bacterial bile salt hydrolases

Bile salt hydrolase (BSH) enzymes are widely expressed by human gut bacteria and catalyze the gateway reaction leading to secondary bile acid formation. Bile acids regulate key metabolic and immune processes by binding to host receptors. There is an unmet need for a potent tool to inhibit BSHs across all gut bacteria to study the effects of bile acids on host physiology. Here, we report the development of a covalent pan-inhibitor of gut bacterial BSHs. From a rationally designed candidate library, we identified a lead compound bearing an alpha-fluoromethyl ketone warhead that modifies BSH at the catalytic cysteine residue. This inhibitor abolished BSH activity in conventional mouse feces. Mice gavaged with a single dose of this compound displayed decreased BSH activity and decreased deconjugated bile acid levels in feces. Our studies demonstrate the potential of a covalent BSH inhibitor to modulate bile acid composition in vivo.
Microbending fiber-optic sensor design optimization

Periodic microbending along the axis of an optical fiber causes mode coupling which couples light from core modes to other core modes or to cladding modes. By monitoring the light power of core1 or cladding2 modes an applied field (pressure, displacement, acceleration) can be detected. Design considerations for optimum performance of such an intensity modulated microbending acoustooptic fiber sensor are discussed, and the relevant design parameters are given. The equivalent acoustic circuit of the sensor is determined, and its acoustic frequency response is predicted. From this analysis, designs for optimum sensor performance can then be made.
A Computer Code for Topological Quantum Spin Systems over Triangulated Surfaces

We derive explicit closed-form matrix representations of Hamiltonians drawn from tensored algebras, such as quantum spin Hamiltonians. These formulas enable us to soft-code generic Hamiltonian syst...
Simulations of three adaptive, decentralized controlled, job scheduling algorithms

Abstract Simulation results of three adaptive, decentralized controlled job scheduling algorithms which assume absolutely no a priori knowledge about jobs are presented. The results provide insight into the workings and relative effectiveness of the three algorithms, as well as insight into the performance of a special type of decentralized control. The simulation approach includes tuning the parameters of each algorithm, and then comparing the three algorithms based on response time, load balancing and the percentage of job movement. Each of the algorithm is compared under light, moderate, and heavy loads in the system, as well as a function of the traffic in the communication subnet and the scheduling interval. Modifications to the models are then introduced to further investigate the impact of various other parameters such as the cost of the scheduling algorithm itself, the effect of highly degraded state information and eliminating the movement of large (in size) jobs. Three simple analytical models are also presented and compared to the simulation results. A general observation is that, if tuned correctly, the decentralized algorithms exhibit stable behavior and considerably improve performance (response time and load balancing) at modest cost (percentage of job movement and algorithm execution cost).
Ring Laser Gyroscope Tests of Lorentz Symmetry

Interferometric gyroscope systems are being developed with the goal of measuring general-relativistic effects including frame-dragging effects. Such devices are also capable of performing searches for Lorentz violation. We summarize efforts that relate gyroscope measurements to coefficients for Lorentz violation in the gravity sector of the Standard-Model Extension.
Packing and Covering Directed Triangles

We prove that if a directed multigraph D has at most t pairwise arc-disjoint directed triangles, then there exists a set of less than 2t arcs in D which meets all directed triangles in D, except in the trivial case $$t=0$$. This answers affirmatively a question of Tuza from 1990.
Revisiting the gender wage gap in the United States

Abstract In this paper, we revisit the gender wage inequality in the United States with a focus on the deciles level wage-distribution in the USA during 1986 to 2016. We find that with the inclusion of part time employed men and women, the overall ratio of women’s to men’s wages in 1986 was 53 percent and this ratio increased to 67 percent as of 2016, suggesting a very moderate decline in overall gender wage gap over three decades. Moreover, our study decomposes the trends of the gender wage gap by the deciles and provides a description of the trends at the decile level for the recent years. We find that a higher gender unemployment gap has been associated with lower gender wage gap. Moreover, although the wage gap has declined moderately, within each gender, the wage-income share of the bottom decile to the top decile has dropped (and Coefficient of Variation has gone up), with a higher magnitude for women, suggesting an increase in wage inequality within each gender with a higher intensity for women. Finally, we demonstrate that traditional economic “reasons” for the gender wage gap–part time jobs and lack of skill–fail to explain the current gap convincingly, indicating an implicit gender discrimination.
Incidence Geometry in a Weyl Chamber I: $GL_n$

Abstract We study the central hyperplane arrangement whose hyperplanes are the vanishing loci of the weights of the first and the second fundamental representations of gl n restricted to the dual fundamental Weyl chamber. We obtain generating functions that count flats and faces of a given dimension. This counting is interpreted in physics as the enumeration of the phases of the Coulomb and mixed Coulomb-Higgs branches of a five-dimensional gauge theory with 8 supercharges in presence of hypermultiplets transforming in the fundamental and antisymmetric representation of a U ( n ) gauge group as described by the Intriligator-Morrison-Seiberg superpotential.
Child Poverty, the Great Recession, and the Social Safety Net in the United States.

In this paper, we comprehensively examine the effects of the Great Recession on child poverty, with particular attention to the role of the social safety net in mitigating the adverse effects of shocks to earnings and income. Using a state panel data model and data for 2000 to 2014, we estimate the relationship between the business cycle and child poverty, and we examine how and to what extent the safety net is providing protection to at-risk children. We find compelling evidence that the safety net provides protection; that is, the cyclicality of after-tax-and-transfer child poverty is significantly attenuated relative to the cyclicality of private income poverty. We also find that the protective effect of the safety net is not similar across demographic groups, and that children from more disadvantaged backgrounds, such as those living with Hispanic or single heads, or particularly those living with immigrant household heads—or immigrant spouses—experience larger poverty cyclicality than those living with non- Hispanic white or married heads, or those living with native household heads with native spouses. Our findings hold across a host of choices for how to define poverty. These include measures based on absolute thresholds or more relative thresholds. They also hold for measures of resources that include not only cash and near-cash transfers net of taxes but also several measures of the value of public medical benefits.
An environmental DNA tool for monitoring the status of the Critically Endangered Smalltooth Sawfish, Pristis pectinata, in the western Atlantic

The Critically Endangered Smalltooth Sawfish, Pristis pectinata, was once widespread in the tropical and subtropical waters of the Atlantic Ocean, but following substantial declines over the past century, the remaining population(s) are currently confined to Florida in the U.S., and the Bahamas. Recent research and verified public encounter reports suggest that the core population in south and southwest Florida may be stabilizing and potentially expanding into formerly occupied areas of their historic range in the western Atlantic; however, the status of this species outside of core waters is not well understood. Environmental DNA (eDNA) methods provide a relatively cost effective and rapid assessment tool for monitoring species occurrence in aquatic habitats. Here, we have developed an eDNA tool: a species-specific Droplet Digital™ PCR assay targeting a 100-base pair portion of the mitochondrial NADH dehydrogenase subunit 2 gene in P. pectinata, with the ability to reliably detect as little as 0.25 pg of target DNA. The assay was validated by analyzing a water sample from an occupied nursery in southwest Florida, which was found to contain an average of 11.54 copies of target DNA/µL (SE = 0.72) in the reaction. The assay was then further tested by placing a juvenile sawfish in an ex situ tank and analyzing water samples collected at time intervals. The implementation of this eDNA tool into field surveys will provide additional, reliable data to assess species recovery and aid in prioritizing localities in which to focus new research, conservation, and education initiatives.
Optical and UV spectroscopy of the peculiar RS CVn system RT Lacertae.

H-alpha and H-beta spectra of the peculiar double-lined RS CVn binary RT Lacertae have been obtained using the IUE, together with a ground-based coude-feed telescope at KPNO. The ground-based spectra show an asymmetry related to the orbital phase in the H-alpha profile. H-beta profiles showed excess emission in one hemisphere and excess absorption in the other, with a broad Gaussian emission component superposed on the excess H-alpha line. A radial velocity curve was derived to estimate the mass ratio and geometry of the system. It is shown that the component of RT Lac fills 80-90 percent of the equilibrium Roche surface. Low-resolution ultraviolet data show that the supposed cooler component is bluer than its companion, suggesting evidence of a scattering shell or a cloud produced by the splash of a gas stream. The phase behavior of the low resolution ultraviolet data support the conclusion that RT Lac is a mass transfer system and that mass transfer is the primary cause of its activity.
Vanadium spin qubits as telecom quantum emitters in silicon carbide.

Solid-state quantum emitters with spin registers are promising platforms for quantum communication, yet few emit in the narrow telecom band necessary for low-loss fiber networks. Here, we create and isolate near-surface single vanadium dopants in silicon carbide (SiC) with stable and narrow emission in the O band, with brightness allowing cavity-free detection in a wafer-scale material. In vanadium ensembles, we characterize the complex d1 orbital physics in all five available sites in 4H-SiC and 6H-SiC. The optical transitions are sensitive to mass shifts from local silicon and carbon isotopes, enabling optically resolved nuclear spin registers. Optically detected magnetic resonance in the ground and excited orbital states reveals a variety of hyperfine interactions with the vanadium nuclear spin and clock transitions for quantum memories. Last, we demonstrate coherent quantum control of the spin state. These results provide a path for telecom emitters in the solid state for quantum applications.
Californium Isotopes from Bombardment of Uranium with Carbon Ions

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GLOBALIZATION AND THE GAINS FROM VARIETY

Since the seminal work of Krugman (1979), product variety has played a central role in models of trade and growth. In spite of the general use of love-of-variety models, there has been no systematic study of how the import of new varieties has contributed to national welfare gains in the United States. In this paper we show that the unmeasured growth in product variety from US imports has been an important source of gains from trade over the last three decades (1972-2001). Using extremely disaggregated data, we show that the number of imported product varieties has increased by a factor of four. We also estimate the elasticities of substitution for each available category at the same level of aggregation, and describe their behavior across time and SITC-5 industries. Using these estimates we develop an exact price index and find that the upward bias in the conventional import price index is approximately 1.2 percent per year – double the estimated impact due to hedonic adjustments on the CPI. The magnitude of this bias suggests that the welfare gains from variety growth in imports alone are 2.8 percent of GDP per year.
Color Correlations in the Proton

A general QCD light front formalism to compute many-body color charge correlation functions due to quarks in the proton was constructed~\cite{Dumitru:2018vpr}. These enable new studies of color charge distributions in the nucleon. The analogies between such correlation functions to electric and magnetization charge densities in the proton and also to nucleon-nucleon correlations in the nucleus are discussed. Including the color charge correlations leads naturally to the removal of infrared divergences that occurs in two- and three-gluon exchange interactions in $q\bar q$-proton scattering. Extensions to include gluonic color charge correlations are discussed.
A polynomial lower bound on adaptive complexity of submodular maximization

In large-data applications, it is desirable to design algorithms with a high degree of parallelization. In the context of submodular optimization, adaptive complexity has become a widely-used measure of an algorithm’s “sequentiality”. Algorithms in the adaptive model proceed in rounds, and can issue polynomially many queries to a function f in each round. The queries in each round must be independent, produced by a computation that depends only on query results obtained in previous rounds. In this work, we examine two fundamental variants of submodular maximization in the adaptive complexity model: cardinality-constrained monotone maximization, and unconstrained non-mono-tone maximization. Our main result is that an r-round algorithm for cardinality-constrained monotone maximization cannot achieve an approximation factor better than 1 − 1/e − Ω(min{ 1/r, log2 n/r 3 }), for any r n c (where c>0 is some constant). This is the first result showing that the number of rounds must blow up polynomially large as we approach the optimal factor of 1−1/e. For the unconstrained non-monotone maximization problem, we show a positive result: For every instance, and every δ>0, either we obtain a (1/2−δ)-approximation in 1 round, or a (1/2+Ω(δ2))-approximation in O(1/δ2) rounds. In particular (and in contrast to the cardinality-constrained case), there cannot be an instance where (i) it is impossible to achieve an approximation factor better than 1/2 regardless of the number of rounds, and (ii) it takes r rounds to achieve a factor of 1/2−O(1/r).
Sharp Asymptotics and Optimal Performance for Inference in Binary Models.

We study convex empirical risk minimization for high-dimensional inference in binary models. Our first result sharply predicts the statistical performance of such estimators in the linear asymptotic regime under isotropic Gaussian features. Importantly, the predictions hold for a wide class of convex loss functions, which we exploit in order to prove a bound on the best achievable performance among them. Notably, we show that the proposed bound is tight for popular binary models (such as Signed, Logistic or Probit), by constructing appropriate loss functions that achieve it. More interestingly, for binary linear classification under the Logistic and Probit models, we prove that the performance of least-squares is no worse than 0.997 and 0.98 times the optimal one. Numerical simulations corroborate our theoretical findings and suggest they are accurate even for relatively small problem dimensions.
Manipulation with Shared Grasping

A shared grasp is a grasp formed by contacts between the manipulated object and both the robot hand and the environment. By trading off hand contacts for environmental contacts, a shared grasp requires fewer contacts with the hand, and enables manipulation even when a full grasp is not possible. Previous research has used shared grasps for non-prehensile manipulation such as pivoting and tumbling. This paper treats the problem more generally, with methods to select the best shared grasp and robot actions for a desired object motion. The central issue is to evaluate the feasible contact modes: for each contact, whether that contact will remain active, and whether slip will occur. Robustness is important. When a contact mode fails, e.g., when a contact is lost, or when unintentional slip occurs, the operation will fail, and in some cases damage may occur. In this work, we enumerate all feasible contact modes, calculate corresponding controls, and select the most robust candidate. We can also optimize the contact geometry for robustness. This paper employs quasi-static analysis of planar rigid bodies with Coulomb friction to derive the algorithms and controls. Finally, we demonstrate the robustness of shared grasping and the use of our methods in representative experiments and examples. The video can be found at this https URL
Lead independent directors and investment efficiency

Abstract I show that the presence of a lead independent director on the corporate board is positively associated with investment efficiency. The result is more pronounced for firms with weaker corporate governance standards, less transparent financial disclosure, and greater financial constraints. The lead director presence is negatively associated with overinvestment (underinvestment) for firms with large cash balances and low leverage (high cash flow volatility). Moreover, the lead director investment-related committee membership as well as CEO power matter in this setting. The lead director board role is also positively associated with future firm performance.
The conjugate gradient algorithm on well-conditioned Wishart matrices is almost deterministic

We prove that the number of iterations required to solve a random positive definite linear system with the conjugate gradient algorithm is almost deterministic for large matrices. We treat the case of Wishart matrices $W = XX^*$ where $X$ is $n \times m$ and $n/m \sim d$ for $0 < d < 1$. Precisely, we prove that for most choices of error tolerance, as the matrix increases in size, the probability that the iteration count deviates from an explicit deterministic value tends to zero. In addition, for a fixed iteration count, we show that the norm of the error vector and the norm of the residual converge exponentially fast in probability, converge in mean and converge almost surely.
Software-Based Monitoring and Analysis of a USB Host Controller Subject to Electrostatic Discharge

Observing, understanding, and mitigating the effects of failure in embedded systems is essential for building dependable control systems. We develop a software-based monitoring methodology to further this goal. This methodology can be applied to any embedded system peripheral and allows the system to operate normally while the monitoring software is running. We use software to instrument the operating system kernel and record indicators of system behavior. By comparing those indicators against baseline indicators of normal system operation, faults can be detected and appropriate action can be taken.We implement this methodology to detect faults caused by electrostatic discharge in a USB host controller. As indicators, we select specific control registers that provide a manifestation of the internal execution of the host controller. Analysis of the recorded register values reveals differences in system execution when the system is subject to interference. This improved understanding of system behavior may lead to better hardware and software mitigation of electrostatic discharge and assist in root-cause analysis and repair of failures.
COVID-19 and Unequal Social Distancing across Demographic Groups

Abstract This paper analyzes whether social distancing experienced by alternative demographic groups within the U S has been different amid COVID-19 The formal investigation is achieved by using daily state-level mobility data from the U S covering information on the demographic categories of income, education and race/ethnicity The results show that social distancing has been experienced more by higher-income, higher-educated or Asian people after the declaration of National Emergency on March 13th, 2020 Since alternative demographic groups were subject to alternative employment opportunities during this period (e g , due to being able to work from home), it is implied that COVID-19 has redistributive effects that require demographic-group specific policies
Screenplay Quality Assessment: Can We Predict Who Gets Nominated?

Deciding which scripts to turn into movies is a costly and time-consuming process for filmmakers. Thus, building a tool to aid script selection, an initial phase in movie production, can be very beneficial. Toward that goal, in this work, we present a method to evaluate the quality of a screenplay based on linguistic cues. We address this in a two-fold approach: (1) we define the task as predicting nominations of scripts at major film awards with the hypothesis that the peer-recognized scripts should have a greater chance to succeed. (2) based on industry opinions and narratology, we extract and integrate domain-specific features into common classification techniques. We face two challenges (1) scripts are much longer than other document datasets (2) nominated scripts are limited and thus difficult to collect. However, with narratology-inspired modeling and domain features, our approach offers clear improvements over strong baselines. Our work provides a new approach for future work in screenplay analysis.
The Splitting Theorem and topology of noncompact spaces with nonnegative N-Bakry Émery Ricci curvature

In this paper, we generalize topological results known for noncompact manifolds with nonnegative Ricci curvature to spaces with nonnegative $N$-Bakry Emery Ricci curvature. We study the Splitting Theorem and a property called the geodesic loops to infinity property in relation to spaces with nonnegative $N$-Bakry Emery Ricci Curvature. In addition, we show that if $M^n$ is a complete, noncompact Riemannian manifold with nonnegative $N$-Bakry Emery Ricci curvature where $N>n$, then $H_{n-1}(M,\mathbb{Z})$ is $0$.
Derivation of non-classical stochastic price dynamics equations

Abstract We analyze the relative price change of assets starting from basic supply/demand considerations subject to arbitrary motivations. The resulting stochastic differential equation has coefficients that are functions of supply and demand. We derive these rigorously. The variance in the relative price change is then also dependent on the supply and demand, and is closely connected to the expected return. An important consequence for risk assessment and options pricing is the implication that variance is highest when the magnitude of price change is greatest, and lowest near market extrema. This occurs even if supply and demand are not dependent on price trend. The stochastic equation differs from the standard equation in mathematical finance in which the expected return and variance are decoupled. The methodology has implications for the basic framework for risk assessment, suggesting that volatility should be measured in the context of regimes of price change. The model we propose shows how investors are often misled by the apparent calm of markets near a market peak. Risk assessment methods utilizing volatility can be improved using this formulation.
Hedge fund activism, CEO turnover and compensation

Abstract This paper examines the governance role of hedge fund activists by analyzing the impact of these activists on CEO turnover, CEO pay, and CEO pay-performance link in targeted companies. Using the difference-in-difference approach, we first find significantly higher CEO turnover following hedge fund activism. After we split target companies into the CEO-turnover and non-CEO-turnover sub-samples, we find that only new CEOs in targeted companies get more compensation following hedge fund activism while incumbent CEO pay does not significantly change. The relationship between CEO bonuses and return on assets following hedge fund activism also differs across the subsamples split by CEO turnover. Pay-performance relationship is enhanced by hedge fund activism for new CEOs, but not for incumbent CEOs. In additional analyses, we document that CEO turnover is positively associated with Tobin’s Q and shareholder votes on Say on Pay in target companies after hedge fund activism.
Management of the aortic root in type A aortic dissection: A valve sparing approach.

Background Type A acute aortic dissection (TAAAD) is rapidly fatal without emergency repair. Surgical outcomes have improved over the years with improvements in technique and postoperative care. Classically, supracomissural aortic replacement has been the standard of care. However, reintervention rates, particularly on the aortic root in certain groups of patients, shifted the focus towards improving long-term results of surgical repair. With regard to the aortic root, root replacement has been the gold standard. However, the surgical community realized that valve replacement in itself is a disease, and valve sparing aortic root replacement (VSRR) took center stage in the care of these patients. Methods We searched the Pubmed and EMBASE databases for articles related to VSRR and composite valve conduit (CVC) root replacement, and the long-term results of these techniques in TAAAD. Results Supracomissural repair is limited by reintervention, and CVC results are affected by complications related to the prosthetic valve. Conversely, VSRR is associated with good short-term outcomes, improvement in quality of life, and it is durable. Conclusion VSRR is a sound technique in TAAAD in experienced hands.
Restricted Percolation Critical Exponents in High Dimensions

Despite great progress in the study of critical percolation on $\mathbb{Z}^d$ for $d$ large, properties of critical clusters in high-dimensional fractional spaces and boxes remain poorly understood, unlike the situation in two dimensions. Closely related models such as critical branching random walk give natural conjectures for the value of the relevant high-dimensional critical exponents; see in particular the conjecture by Kozma-Nachmias that the probability that $0$ and $(n, n, n, \ldots)$ are connected within $[-n,n]^d$ scales as $n^{-2-2d}$. In this paper, we study the properties of critical clusters in high-dimensional half-spaces and boxes. In half-spaces, we show that the probability of an open connection ("arm") from $0$ to the boundary of a sidelength $n$ box scales as $n^{-3}$. We also find the scaling of the half-space two-point function (the probability of an open connection between two vertices) and the tail of the cluster size distribution. In boxes, we obtain the scaling of the two-point function between vertices which are any macroscopic distance away from the boundary.
THE CASE OF THE MIGRATING LOOP RECORDER

Implantable loop recorders (ILR) have been increasingly utilized for the evaluation as well as the diagnosis of unexplained palpitations or syncope. A 36 year old male underwent ILR implantation by his cardiologist one week prior to presenting to the ED complaining of left chest and flank pain. The
Model of a solar system in the conservative geometry

Pandres has shown that an enlargement of the covariance group to the group of conservative transformations leads to a richer geometry than that of general relativity. Using orthonormal tetrads as field variables, the fundamental geometric object is the curvature vector denoted by $$C_\mu $$ . From an appropriate scalar Lagrangian field equations for both free-field and the field with sources have been developed. We first review models which use a free-field solution to model the Solar System and why these results are unacceptable. We also show that the standard Schwarzschild metric is also unacceptable in our theory. Finally we show that there are solutions which involve sources which agree with general relativity PPN parameters and thus approximate the Schwarzschild solution. The main difference is that the Einstein tensor is not identically zero but includes small values for the density, radial pressure and tangential pressure. Higher precision experiments should be able to determine the validity of these models. These results add further confirmation that the theory developed by Pandres is the fundamental theory of physics.
Deterministic Generation of All-Photonic Quantum Repeaters from Solid-State Emitters

Quantum repeaters allow for reliable transmission of quantum information over long distances. One possible approach relies on highly entangled photons. A new protocol provides a way to generate arbitrarily large states of entangled photons using just one emitter coupled to a single qubit.
The mod 2 homology of infinite loopspaces

Applying mod 2 homology to the Goodwillie tower of the functor sending a spectrum X to the suspension spectrum of its 0th space, leads to a spectral sequence for computing H .X IZ=2/ , which converges strongly when X is 0–connected. The E term is the homology of the extended powers of X , and thus is a well known functor of H .X IZ=2/ , including structure as a bigraded Hopf algebra, a right module over the mod 2 Steenrod algebra A , and a left module over the Dyer–Lashof operations. This paper is an investigation of how this structure is transformed through the spectral sequence.
SGR 1806–20 Is a Set of Independent Relaxation Systems

SGR 1806-20 produced patterns of bursts during its 1983 outburst that indicate multiple independent energy accumulation sites, each driven by a continuous power source, with sudden, incomplete releases of the accumulated energy. The strengths of the power sources and their durations of activity vary over several orders of magnitude.
Lessons of quantum 2D dilaton gravity

Abstract Based on the analysis of two dimensional dilaton gravity we argue that the semiclassical equations of black hole formation and evaporation should not be interpreted in terms of expectation values of operators in the exact quantum theory, but rather as WKB trajectories. Thus at the semiclassical level it does not seem possible to formulate a notion of quantum mechanical information loss.
Perspective: (Beyond) spin transport in insulators

Insulating materials with dynamical spin degrees of freedom have recently emerged as viable conduits for spin flows. Transport phenomena harbored therein are, however, turning out to be much richer than initially envisioned. In particular, the topological properties of the collective order-parameter textures can give rise to conservation laws that are not based on any specific symmetries. The emergent continuity relations are thus robust against structural imperfections and anisotropies, which would be detrimental to the conventional spin currents (that rely on approximate spin-rotational symmetries). The underlying fluxes thus supersede the notion of spin flow in insulators, setting the stage for nonequilibrium phenomena termed topological hydrodynamics. Here, we outline our current understanding of the essential ingredients, based on the energetics of the electrically-controlled injection of topological flows through interfaces, along with a reciprocal signal generation by the outflow of the conserved quantity. We will focus on two examples for the latter: winding dynamics in one-dimensional systems, which supplants spin superfluidity of axially-symmetric easy-plane magnets, and skyrmion dynamics in two-dimensional Heisenberg-type magnets. These examples will illustrate the essential common aspects of topological flows and hint on generic strategies for their generation and detection in spintronic systems. Generalizations to other dimensions and types of order-parameter spaces will also be briefly discussed.
Starquake-induced Magnetic Field and Torque Evolution in Neutron Stars

The persistent increases in spin-down rate (offsets) seen to accompany glitches in the Crab and other pulsars suggest increases in the spin-down torque. We interpret these offsets as due to starquakes occurring as the star spins down and the rigid crust becomes less oblate. We study the evolution of strain in the crust, the initiation of starquakes, and possible consequences for magnetic field and torque evolution. Crust cracking occurs as equatorial material shears under the compressive forces arising from the star's decreasing circumference and as matter moves to higher latitudes along a fault inclined to the equator. A starquake is most likely to originate near one of the two points on the rotational equator farthest from the magnetic poles. The material breaks along a fault approximately aligned with the magnetic poles. We suggest that the observed offsets come about when a starquake perturbs the star's mass distribution, producing a misalignment of the angular momentum and spin axes. Subsequently, damped precession to a new rotational state increases the angle α between the rotation and magnetic axes. The resulting increase in external torque appears as a permanent increase in the spin-down rate. Repeated starquakes would continue to increase α, making the pulsar more of an orthogonal rotator.
Symbols of one-loop integrals from mixed Tate motives

We use a result on mixed Tate motives due to Goncharov [1] to show that the symbol of an arbitrary one-loop 2 m-gon integral in 2 m dimensions may be read off directly from its Feynman parameterization. The algorithm proceeds via recursion in m seeded by the well-known box integrals in four dimensions. As a simple application of this method we write down the symbol of a three-mass hexagon integral in six dimensions.
Hill’s Equation with Random Forcing Parameters: Determination of Growth Rates Through Random Matrices

This paper derives expressions for the growth rates for the random 2×2 matrices that result from solutions to the random Hill’s equation. The parameters that appear in Hill’s equation include the forcing strength q k and oscillation frequency λ k . The development of the solutions to this periodic differential equation can be described by a discrete map, where the matrix elements are given by the principal solutions for each cycle. Variations in the (q k ,λ k ) lead to matrix elements that vary from cycle to cycle. This paper presents an analysis of the growth rates including cases where all of the cycles are highly unstable, where some cycles are near the stability border, and where the map would be stable in the absence of fluctuations. For all of these regimes, we provide expressions for the growth rates of the matrices that describe the solutions.
Structural, electronic, and magnetic properties of Vanadium-based Janus dichalcogenide monolayers: A first-principles study

The structural, electronic, and magnetic properties of VSSe, VSeTe, and VSTe monolayers in both 2H and 1T phases are investigated via first-principles calculations. The 2H phase is energetically favorable in VSSe and VSeTe, whereas the 1T phase is lower in energy in VSTe. For V-based Janus monolayers in the 2H phase, calculations of the magnetic anisotropy show an easy-plane for the magnetic moment. As such, they should not exhibit a ferromagnetic phase transition, but instead, a Berezinskii-Kosterlitz-Thouless (BKT) transition. A classical XY model with nearest-neighbor coupling estimates critical temperatures (${\mathrm{T}}_{\text{BKT}}$) ranging from 106 K for VSSe to 46 K for VSTe.
Compound Poisson Law for Hitting Times to Periodic Orbits in Two-Dimensional Hyperbolic Systems

We show that a compound Poisson distribution holds for scaled exceedances of observables $$\phi $$ uniquely maximized at a periodic point $$\zeta $$ in a variety of two-dimensional hyperbolic dynamical systems with singularities $$(M,T,\mu )$$ , including the billiard maps of Sinai dispersing billiards in both the finite and infinite horizon case. The observable we consider is of form $$\phi (z)=-\ln d(z,\zeta )$$ where d is a metric defined in terms of the stable and unstable foliation. The compound Poisson process we obtain is a Polya-Aeppli distibution of index $$\theta $$ . We calculate $$\theta $$ in terms of the derivative of the map T. Furthermore if we define $$M_n=\max \{\phi ,\ldots ,\phi \circ T^n\}$$ and $$u_n (\tau )$$ by $$\lim _{n\rightarrow \infty } n\mu (\phi >u_n (\tau ) )=\tau $$ the maximal process satisfies an extreme value law of form $$\mu (M_n \le u_n)=e^{-\theta \tau }$$ . These results generalize to a broader class of functions maximized at $$\zeta $$ , though the formulas regarding the parameters in the distribution need to be modified.
Distinct Distances on Curves Via Rigidity

It is shown that \(N\) points on a real algebraic curve of degree \(n\) in \({\mathbb R}^d\) always determine \(\gtrsim _{n,d}\)\({N^{1+\frac{1}{4}}}\) distinct distances, unless the curve is a straight line or the closed geodesic of a flat torus. In the latter case, there are arrangements of \(N\) points which determine \(\lesssim \)\({N}\) distinct distances. The method may be applied to other quantities of interest to obtain analogous exponent gaps. An important step in the proof involves understanding the structural rigidity of certain frameworks on curves.
Relative Orientation of Pairs of Spiral Galaxies in the Sloan Digital Sky Survey

From our study of binary spiral galaxies in the Sloan Digital Sky Survey Data Release 6, we find that the relative orientation of disks in binary spiral galaxies is consistent with their being drawn from a random distribution of orientations. For 747 isolated pairs of luminous disk galaxies, the distribution of , the angle between the major axes of the galaxy images, is consistent with a uniform distribution on the interval [0°, 90°]. With the assumption that the disk galaxies are oblate spheroids, we can compute cos β, where β is the angle between the rotation axes of the disks. In the case that one galaxy in the binary is face-on or edge-on, the tilt ambiguity is resolved, and cos β can be computed unambiguously. For 94 isolated pairs with at least one face-on member, and for 171 isolated pairs with at least one edge-on member, the distribution of cos β is statistically consistent with the distribution of cos i for isolated disk galaxies. This result is consistent with random orientations of the disks within pairs.
Common Probability Patterns Arise from Simple Invariances

Shift and stretch invariance lead to the exponential-Boltzmann probability distribution. Rotational invariance generates the Gaussian distribution. Particular scaling relations transform the canonical exponential and Gaussian patterns into the variety of commonly observed patterns. The scaling relations themselves arise from the fundamental invariances of shift, stretch and rotation, plus a few additional invariances. Prior work described the three fundamental invariances as a consequence of the equilibrium canonical ensemble of statistical mechanics or the Jaynesian maximization of information entropy. By contrast, I emphasize the primacy and sufficiency of invariance alone to explain the commonly observed patterns. Primary invariance naturally creates the array of commonly observed scaling relations and associated probability patterns, whereas the classical approaches derived from statistical mechanics or information theory require special assumptions to derive commonly observed scales.
Ask the GRU: Multi-task Learning for Deep Text Recommendations

In a variety of application domains the content to be recommended to users is associated with text. This includes research papers, movies with associated plot summaries, news articles, blog posts, etc. Recommendation approaches based on latent factor models can be extended naturally to leverage text by employing an explicit mapping from text to factors. This enables recommendations for new, unseen content, and may generalize better, since the factors for all items are produced by a compactly-parametrized model. Previous work has used topic models or averages of word embeddings for this mapping. In this paper we present a method leveraging deep recurrent neural networks to encode the text sequence into a latent vector, specifically gated recurrent units (GRUs) trained end-to-end on the collaborative filtering task. For the task of scientific paper recommendation, this yields models with significantly higher accuracy. In cold-start scenarios, we beat the previous state-of-the-art, all of which ignore word order. Performance is further improved by multi-task learning, where the text encoder network is trained for a combination of content recommendation and item metadata prediction. This regularizes the collaborative filtering model, ameliorating the problem of sparsity of the observed rating matrix.
EARLY- AND LATE-TIME OBSERVATIONS OF SN 2008ha: ADDITIONAL CONSTRAINTS FOR THE PROGENITOR AND EXPLOSION

We present a new maximum-light optical spectrum of the extremely low luminosity and exceptionally low-energy Type Ia supernova (SN Ia) 2008ha, obtained one week before the earliest published spectrum. Previous observations of SN 2008ha were unable to distinguish between a massive star and white dwarf (WD) origin for the SN. The new maximum-light spectrum, obtained one week before the earliest previously published spectrum, unambiguously shows features corresponding to intermediate mass elements, including silicon, sulfur, and carbon. Although strong silicon features are seen in some core-collapse SNe, sulfur features, which are a signature of carbon/oxygen burning, have always been observed to be weak in such events. It is therefore likely that SN 2008ha was the result of a thermonuclear explosion of a carbon-oxygen WD. Carbon features at maximum light show that unburned material is present to significant depths in the SN ejecta, strengthening the case that SN 2008ha was a failed deflagration. We also present late-time imaging and spectroscopy that are consistent with this scenario.
Cardinal characteristics and countable Borel equivalence relations

Boykin and Jackson recently introduced a property of countable Borel equivalence relations called Borel boundedness, which they showed is closely related to the union problem for hyperfinite equivalence relations. In this paper, we introduce a family of properties of countable Borel equivalence relations which correspond to combinatorial cardinal characteristics of the continuum in the same way that Borel boundedness corresponds to the bounding number b. We analyze some of the basic behavior of these properties, showing, e.g., that the property corresponding to the splitting number s coincides with smoothness. We then settle many of the implication relationships between the properties; these relationships turn out to be closely related to (but not the same as) the Borel Tukey ordering on cardinal characteristics.