cssi/SciSciGPT-SciSciNet huggingface dataset:
A Covert Queueing Channel in FCFS Schedulers

We study covert queueing channels (CQCs), which are a kind of covert timing channel that may be exploited in shared queues across supposedly isolated users. In our system model, a user sends messages to another user via his pattern of access to the shared resource, which serves the users according to a first come first served (FCFS) policy. One example of such a channel is the cross-virtual network covert channel in data center networks, resulting from the queueing effects of the shared resource. First, we study a system comprising a transmitter and a receiver that share a deterministic and work-conserving FCFS scheduler, and we compute the capacity of this channel. We also consider the effect of the presence of other users on the information transmission rate of this channel. The achievable information transmission rates obtained in this paper demonstrate the possibility of significant information leakage and great privacy threats brought by CQCs in FCFS schedulers.
The Bloch–Okounkov Correlation Functions, a Classical Half-integral Case

Bloch and Okounkov’s correlation function on the infinite wedge space has connections to Gromov-Witten theory, Hilbert schemes, symmetric groups, and certain character functions of \({\widehat{ \mathfrak{gl} }_\infty}\) -modules of level one. Recent works have calculated these character functions for higher levels for \({\widehat{ \mathfrak{gl} }_\infty}\) and its Lie subalgebras of classical type. Here we obtain these functions for the subalgebra of type D of half-integral levels and as a byproduct, obtain q-dimension formulas for integral modules of type D at half-integral level.
Boundary superstring field theory

Abstract Using the Batalin–Vilkovisky formalism we provide a detailed analysis of the NS sector of boundary superstring field theory. We construct explicitly the relevant BV structure and derive the master action. Furthermore, we show that this action is exactly equal to the superdisk worldsheet partition function as was recently conjectured.
Integrating remote monitoring into heart failure patients' care regimen: A pilot study.

Author(s): Sohn, Albert; Speier, William; Lan, Esther; Aoki, Kymberly; Fonarow, Gregg C; Ong, Michael K; Arnold, Corey W | Abstract: BackgroundAround 50% of hospital readmissions due to heart failure are preventable, with lack of adherence to prescribed self-care as a driving factor. Remote tracking and reminders issued by mobile health devices could help to promote self-care, which could potentially reduce these readmissions.ObjectiveWe sought to investigate two factors: (1) feasibility of enrolling heart failure patients in a remote monitoring regimen that uses wireless sensors and patient-reported outcome measures; and (2) their adherence to using the study devices and completing patient-reported outcome measures.MethodsTwenty heart failure patients participated in piloting a remote monitoring regimen. Data collection included: (1) physical activity using wrist-worn activity trackers; (2) body weight using bathroom scales; (3) medication adherence using smart pill bottles; and (4) patient -reported outcomes using patient-reported outcome measures.ResultsWe evaluated 150 hospitalized heart failure patients and enrolled 20 individuals. Two factors contributed to 50% (65/130) being excluded from the study: smartphone ownership and patient discharge. Over the course of the study, 60.0% of the subjects wore the activity tracker for at least 70% of the hours, and 45.0% used the scale for more than 70% of the days. The pill bottle was used less than 10% of the days by 55.0% of the subjects.ConclusionsOur method of recruiting heart failure patients prior to hospital discharge may not be feasible as the enrollment rate was low. Once enrolled, the majority of subjects maintained a high adherence to wearing the activity tracker but low adherence to using the pill bottle and completing the follow-up surveys. Scale usage was fair, but it received positive reviews from most subjects. Given the observed usage and feedback, we suggest mobile health-driven interventions consider including an activity tracker and bathroom scale. We also recommend administering a shorter survey more regularly and through an easier interface.
Multiple Instance Choquet Integral Classifier Fusion and Regression for Remote Sensing Applications

In classifier (or regression) fusion, the aim is to combine the outputs of several algorithms to boost overall performance. Standard supervised fusion algorithms often require accurate and precise training labels. However, accurate labels may be difficult to obtain in many remote sensing applications. This paper proposes novel classification and regression fusion models that can be trained given ambiguously and imprecisely labeled training data in which the training labels are associated with sets of data points (i.e., “bags”) instead of individual data points (i.e., “instances”) following a multiple-instance learning framework. Experiments were conducted based on the proposed algorithms on both synthetic data and applications such as target detection and crop yield prediction given remote sensing data. The proposed algorithms show effective classification and regression performance.
An Attempt to Describe Frequency-Correlations among kHz QPOs and HBOs by Two-Armed Vertical p-Mode Oscillations: Case of No Magnetic Field

The trapping of two-armed (m = 2) vertical p-mode oscillations in relativistic disks is examined. The disks are assumed to be isothermal in the vertical direction, but are truncated at a certain height by the presence of corona. The same issues were examined in a previous paper (Kato 2012a). In this paper, unlike the previous paper, however, we do not use the approximation that the oscillations are nearly vertical, but limit to a simpler case of no magnetic field. As in the previous paper, the results suggest that the two basic oscillation modes [both are the fundamental (n = 1) in the vertical direction, but in the horizontal direction one is the fundamental (nr = 0) and the other the first overtone (nr = 1)] correspond to the twin kHz QPOs. Second, the oscillation mode, which is the first overtone (n = 2) in the vertical direction and the fundamental in the horizontal direction (nr = 0), will correspond to the horizontal branch oscillation (HBO) of Z-sources. The latter suggests that the horizontal branch of Z-sources is a sequence of temperature change in disks whose vertical thickness is strongly terminated. The temperature increases leftward along the sequence from the apex between the normal and horizontal branches.
Interlacings for Random Walks on Weighted Graphs and the Interchange Process

We study Aldous's conjecture that the spectral gap of the interchange process on a weighted undirected graph equals the spectral gap of the random walk on this graph. We present a conjecture in the form of an inequality and prove that this inequality implies Aldous's conjecture by combining an interlacing result for Laplacians of random walks on weighted graphs with representation theory. We prove the conjectured inequality for several important instances. As an application of the developed theory, we prove Aldous's conjecture for a large class of weighted graphs, which includes all wheel graphs, all graphs with four vertices, certain nonplanar graphs, certain graphs with several weighted cycles of arbitrary length, and all trees. Caputo, Liggett, and Richthammer have recently resolved Aldous's conjecture, after independently and simultaneously discovering the key ideas developed in the present paper.
Combining Enhanced Sampling with Experiment Directed Simulation of the GYG peptide

Experiment-directed simulation (EDS) is a technique to minimally bias molecular dynamics simulations to match experimentally observed results. The method improves accuracy but does not address the ...
Constraining quantum fields using modular theory

Tomita-Takesaki modular theory provides a set of algebraic tools in quantum field theory that is suitable for the study of the information-theoretic properties of states. For every open set in spacetime and choice of two states, the modular theory defines a positive operator known as the relative modular operator that decreases monotonically under restriction to subregions. We study the consequences of this operator monotonicity inequality for correlation functions in quantum field theory. We do so by constructing a one-parameter Renyi family of information-theoretic measures from the relative modular operator that inherit monotonicity by construction and reduce to correlation functions in special cases. In the case of finite quantum systems, this Renyi family is the sandwiched Renyi divergence and we obtain a simple proof of its monotonicity. Its monotonicity implies a class of constraints on correlation functions in quantum field theory, only a small set of which were known to us. We explore these inequalities for free fields and conformal field theory. We conjecture that the second null derivative of Renyi divergence is non-negative which is a generalization of the quantum null energy condition to the Renyi family.
Constraining Gamma-Ray Emission from Luminous Infrared Galaxies with Fermi-LAT; Tentative Detection of Arp 220

Star-forming galaxies produce gamma-rays primarily via pion production, resulting from inelastic collisions between cosmic-ray protons and the interstellar medium (ISM). The dense ISM and high star formation rates of luminous and ultra-luminous infrared galaxies (LIRGs and ULIRGs) imply that they should be strong gamma-ray emitters, but so far only two LIRGs have been detected. Theoretical models for their emission depend on the unknown fraction of cosmic-ray protons that escape these galaxies before interacting. We analyze Fermi-LAT data for 82 of the brightest Infrared Astronomical Satellite LIRGs and ULIRGs. We examine each system individually and carry out a stacking analysis to constrain their gamma-ray fluxes. We report the detection of the nearest ULIRG Arp 220 (~4.6σ). We observe a gamma-ray flux (0.8–100 GeV) of 2.4 × 10−10 phot cm−2 s−1 with a photon index of 2.23 (8.2 × 1041 erg s−1 at 77 Mpc). We also derive upper limits (ULs) for the stacked LIRGs and ULIRGs. The gamma-ray luminosity of Arp 220 and the stacked ULs agree with calorimetric predictions for dense star-forming galaxies. With the detection of Arp 220, we extend the gamma-ray–IR luminosity correlation to the high-luminosity regime with as well as the gamma-ray–radio continuum luminosity correlation with . The current survey of Fermi-LAT is on the verge of detecting more LIRGs/ULIRGs in the local universe, and we expect even more detections with deeper Fermi-LAT observations or the next generation of gamma-ray detectors.
Algebraic linking numbers of knots in 3{manifolds

Relative self-linking and linking \numbers" for pairs of oriented knots and 2{component links in oriented 3{manifolds are dened in terms of intersection invariants of immersed surfaces in 4{manifolds. The resulting concordance invariants generalize the usual homological notion of linking by taking into account the fundamental group of the ambient manifold and of- ten map onto innitely generated groups. The knot invariants generalize the type 1 invariants of Kirk and Livingston and when taken with respect to cer- tain preferred knots, called spherical knots, relative self-linking numbers are characterized geometrically as the complete obstruction to the existence of a singular concordance which has all singularities paired by Whitney disks. This geometric equivalence relation, called W{equivalence, is also related to nite type 1{equivalence (in the sense of Habiro and Goussarov) via the work of Conant and Teichner and represents a \rst order" improvement to an arbitrary singular concordance. For null-homotopic knots, a slightly weaker equivalence relation is shown to admit a group structure. AMS Classication 57M27; 57N10, 57M25
Cusp Formation for a Nonlocal Evolution Equation

Cordoba et al. (Ann Math 162(3):1377–1389, 2005) introduced a nonlocal active scalar equation as a one-dimensional analogue of the surface-quasigeostrophic equation. It has been conjectured, based on numerical evidence, that the solution forms a cusp-like singularity in finite time. Up until now, no active scalar with nonlocal flux is known for which cusp formation has been rigorously shown. In this paper, we introduce and study a nonlocal active scalar, inspired by the Cordoba–Cordoba–Fontelos equation, and prove that either a cusp- or needle-like singularity forms in finite time.
Deriving the Mass Distribution of M87 from Globular Clusters

We describe a maximum likelihood method for determining the mass distribution in spherical stellar systems from the radial velocities of a population of discrete test particles. The method assumes a parametric form for the mass distribution and a nonparametric two-integral distribution function. We apply the method to a sample of 161 globular clusters in M87. We find that the mass within 32 kpc is (2.4 ± 0.6) × 1012 M☉, and the exponent of the density profile ρ ∝ r-α in the range 10-100 kpc is α = 1.6 ± 0.4. The energy distribution suggests a few kinematically distinct groups of globular clusters. The anisotropy of the globular cluster velocity distribution cannot be determined reliably with the present data. Models fitted to an NFW potential yield similar mass estimates but cannot constrain the concentration radius rc in the range 10-500 kpc.
Estimation of Key Sunquake Parameters through Hydrodynamic Modeling and Cross-correlation Analysis

Sunquakes are one of the more distinct secondary phenomena related to solar flares, where energy deposition in the lower layers of the Sun's atmosphere excites acoustic waves easily visible in photospheric dopplergrams. We explore two possible excitation mechanisms of sunquakes in the context of the electron beam hypothesis: an instantaneous transfer of momentum and a gradual applied force due to flare eruption. We model the sunquake excitation and compare with five observed sunquake events using a cross-correlation analysis. We find that at least half the events studied are consistent with the electron beam hypothesis and estimate the energy required to excite the sunquakes to be within the range determined by previous studies.
Resolvent Estimates for Normally Hyperbolic Trapped Sets

We give pole free strips and estimates for resolvents of semiclassical operators which, on the level of the classical flow, have normally hyperbolic smooth trapped sets of codimension two in phase space. Such trapped sets are structurally stable and our motivation comes partly from considering the wave equation for Kerr black holes and their perturbations, whose trapped sets have precisely this structure. We give applications including local smoothing effects with epsilon derivative loss for the Schrodinger propagator as well as local energy decay results for the wave equation.
Continuum eigenmodes in some linear stellar models

We apply parallel approaches in the study of continuous spectra to adiabatic stellar models. We seek continuum eigenmodes for the LAWE formulated as both finite difference and linear differential equations. In particular, we apply methods of Jacobi matrices and methods of subordinancy theory in these respective formulations. We find certain pressure-density conditions which admit positive-measured sets of continuous oscillation spectra under plausible conditions on density and pressure. We arrive at results of unbounded oscillations and computational or, perhaps, dynamic instability.
Relativistic dynamics of point magnetic moment

The covariant motion of a classical point particle with magnetic moment in the presence of (external) electromagnetic fields is revisited. We are interested in understanding extensions to the Lorentz force involving point particle magnetic moment (Stern–Gerlach force) and how the spin precession dynamics is modified for consistency. We introduce spin as a classical particle property inherent to Poincare symmetry of space-time. We propose a covariant formulation of the magnetic force based on a ‘magnetic’ 4-potential and show how the point particle magnetic moment relates to the Amperian (current loop) and Gilbertian (magnetic monopole) descriptions. We show that covariant spin precession lacks a unique form and discuss the connection to $$g-2$$ anomaly. We consider the variational action principle and find that a consistent extension of the Lorentz force to include magnetic spin force is not straightforward. We look at non-covariant particle dynamics, and present a short introduction to the dynamics of (neutral) particles hit by a laser pulse of arbitrary shape.
A Deep Chandra Catalog of X-Ray Point Sources toward the Galactic Center

(abridged) We present a catalog of 2357 point sources detected during 590 ks of Chandra observations of the 17-by-17 arcminute field around Sgr A*. This field encompasses a physical area of 40 by 40 pc at a distance of 8 kpc. The completeness limit of the sample at the Galactic center is 10^{31} erg s^{-1} (2.0--8.0 keV), while the detection limit is an order of magnitude lower. The 281 sources detected below 1.5 keV are mainly in the foreground of the Galactic center, while comparisons to the Chandra deep fields at high Galactic latitudes suggest that only about 100 of the observed sources are background AGN. The surface density of absorbed sources (not detected below 1.5 keV) falls off as 1/theta away from Sgr A*, in agreement with the distribution of stars in infrared surveys. Point sources brighter than our completeness limit produce 10% of the flux previously attributed to diffuse emission. The log(N)-log(S) distribution of the Galactic center sources is extremely steep (power-law slope alpha = 1.7). If this distribution extends down to a flux of 10^{-17} erg cm^{-1} s^{-1} (10^{29} erg s^{-1} at 8 kpc, 2.0--8.0 keV) with the same slope, then point sources would account for all of the previously reported diffuse emission. Therefore, the 2.0--8.0 keV luminosity distribution must flatten between 10^{29} - 10^{31} erg s^{-1}. Finally, the spectra of more than half of the Galactic center sources are very hard, and can be described by a power law ($E^{-Gamma}) with photon index Gamma < 1. Such hard spectra have been seen previously only from magnetically accreting white dwarfs and wind-accreting neutron stars, suggesting that there are large numbers of these systems in our field.
Load Curve Data Cleansing and Imputation Via Sparsity and Low Rank

The smart grid vision is to build an intelligent power network with an unprecedented level of situational awareness and controllability over its services and infrastructure. This paper advocates statistical inference methods to robustify power monitoring tasks against the outlier effects owing to faulty readings and malicious attacks, as well as against missing data due to privacy concerns and communication errors. In this context, a novel load cleansing and imputation scheme is developed leveraging the low intrinsic-dimensionality of spatiotemporal load profiles and the sparse nature of “bad data.” A robust estimator based on principal components pursuit (PCP) is adopted, which effects a twofold sparsity-promoting regularization through an l1-norm of the outliers, and the nuclear norm of the nominal load profiles. Upon recasting the non-separable nuclear norm into a form amenable to decentralized optimization, a distributed (D-) PCP algorithm is developed to carry out the imputation and cleansing tasks using networked devices comprising the so-termed advanced metering infrastructure. If D-PCP converges and a qualification inequality is satisfied, the novel distributed estimator provably attains the performance of its centralized PCP counterpart, which has access to all networkwide data. Computer simulations and tests with real load curve data corroborate the convergence and effectiveness of the novel D-PCP algorithm.
Breeding Super-Earths and Birthing Super-Puffs in Transitional Disks

The riddle posed by super-Earths (1-4$R_\oplus$, 2-20$M_\oplus$) is that they are not Jupiters: their core masses are large enough to trigger runaway gas accretion, yet somehow super-Earths accreted atmospheres that weigh only a few percent of their total mass. We show that this puzzle is solved if super-Earths formed late, as the last vestiges of their parent gas disks were about to clear. This scenario would seem to present fine-tuning problems, but we show that there are none. Ambient gas densities can span many (up to 9) orders of magnitude, and super-Earths can still robustly emerge after $\sim$0.1-1 Myr with percent-by-weight atmospheres. Super-Earth cores are naturally bred in gas-poor environments where gas dynamical friction has weakened sufficiently to allow constituent protocores to merge. So little gas is present at the time of core assembly that cores hardly migrate by disk torques: formation of super-Earths can be in situ. The picture --- that close-in super-Earths form in a gas-poor (but not gas-empty) inner disk, fed continuously by gas that bleeds inward from a more massive outer disk --- recalls the largely evacuated but still accreting inner cavities of transitional protoplanetary disks. We also address the inverse problem presented by super-puffs: an uncommon class of short-period planets seemingly too voluminous for their small masses (4-10$R_\oplus$, 2-6$M_\oplus$). Super-puffs easily acquire their thick atmospheres as dust-free, rapidly cooling worlds outside $\sim$1 AU where nebular gas is colder, less dense, and therefore less opaque. Unlike super-Earths which can form in situ, super-puffs migrated in to their current orbits; they are expected to form the outer links of mean-motion resonant chains, and to exhibit greater water content. We close by confronting observations and itemizing remaining questions.
DGEN: A Test Statistic for Detection of General Introgression Scenarios

When two species hybridize, one outcome is the integration of genetic material from one species into the genome of the other, a process known as introgression. Detecting introgression in genomic data is a very important question in evolutionary biology. However, given that hybridization occurs between closely related species, a complicating factor for introgression detection is the presence of incomplete lineage sorting, or ILS. The D-statistic, famously referred to as the "ABBA-BABA" test, was proposed for introgression detection in the presence of ILS in data sets that consist of four genomes. More recently, D_FOIL - a set of statistics - was introduced to extend the D-statistic to data sets of five genomes. The major contribution of this paper is demonstrating that the invariants underlying both the D-statistic and D_FOIL can be derived automatically from the probability mass functions of gene tree topologies under the null species tree model and alternative phylogenetic network model. Computational requirements aside, this automatic derivation provides a way to generalize these statistics to data sets of any size and with any scenarios of introgression. We demonstrate the accuracy of the general statistic, which we call D_GEN, on simulated data sets with varying rates of introgression, and apply it to an empirical data set of mosquito genomes. We have implemented D_GEN and made it available, both as a graphical user interface tool and as a command-line tool, as part of the freely available, open-source software package ALPHA (https://github.com/chilleo/ALPHA).
The application of community ecology theory to co-infections in wildlife hosts.

Priority effect theory, a foundational concept from community ecology, states that the order and timing of species arrival during species assembly can affect species composition. Although this theory has been applied to co-infecting parasite species, it has almost always been with a single time lag between co-infecting parasites. Thus, how the timing of parasite species arrival affects co-infections and disease remains poorly understood. To address this gap in the literature, we exposed post-metamorphic Cuban tree frogs (Osteopilus septentrionalis) to Ranavirus, the fungus Batrachochytrium dendrobatidis (Bd), a nematode Aplectana hamatospicula, or pairs of these parasites either simultaneously or sequentially at a range of time lags and quantified load of the secondary parasite and host growth, survival and parasite tolerance. Prior exposure to Bd or A. hamatospicula significantly increased viral loads relative to hosts singly infected with Ranavirus, whereas A. hamatospicula loads in hosts were higher when co-exposed to Bd than when co-exposed to Ranavirus. There was a significant positive relationship between time since Ranavirus infection and Bd load, and prior exposure to A. hamatospicula decreased Bd loads compared to simultaneous co-infection with these parasites. Infections with Bd and Ranavirus either singly or in co-infections decreased host growth and survival. This research reveals that time lags between co-infections can affect parasite loads, in line with priority effects theory. As co-infections in the field are unlikely to be simultaneous, an understanding of when co-infections are impacted by time lags between parasite exposures may play a major role in controlling problematic co-infections.
Real-Time Detection of Volatility in Liquidity Provision

Previous research has found that high-frequency traders will vary the bid or offer price rapidly overperiods of milliseconds. This is a benefit to fast traders who can time thier trades with microsecondprecision, however it is a cost to the average market participant due to increased trade execution priceuncertainty. In this analysis we attempt to construct real-time methods for determining whether theliquidity of a security is being altered by high-frequency traders. We find a four-state Markov switchingmodel identifies a state consistent with high-frequency traders affecting liquidity. Moreover, we find thisstate is positicely corrrelated with the prediction error from a deep neural network. This state can beused as a signal to delay market participant orders until the price volatility subsides. This delay wouldonly last tens of milliseconds, and so would not be noticable by the average market participant.
Molecular underpinning of intracellular pH regulation on TMEM16F.

TMEM16F, a dual-function phospholipid scramblase and ion channel, is important in blood coagulation, skeleton development, HIV infection, and cell fusion. Despite advances in understanding its structure and activation mechanism, how TMEM16F is regulated by intracellular factors remains largely elusive. Here we report that TMEM16F lipid scrambling and ion channel activities are strongly influenced by intracellular pH (pHi). We found that low pHi attenuates, whereas high pHi potentiates, TMEM16F channel and scramblase activation under physiological concentrations of intracellular Ca2+ ([Ca2+]i). We further demonstrate that TMEM16F pHi sensitivity depends on [Ca2+]i and exhibits a bell-shaped relationship with [Ca2+]i: TMEM16F channel activation becomes increasingly pHi sensitive from resting [Ca2+]i to micromolar [Ca2+]i, but when [Ca2+]i increases beyond 15 µM, pHi sensitivity gradually diminishes. The mutation of a Ca2+-binding residue that markedly reduces TMEM16F Ca2+ sensitivity (E667Q) maintains the bell-shaped relationship between pHi sensitivity and Ca2+ but causes a dramatic shift of the peak [Ca2+]i from 15 µM to 3 mM. Our biophysical characterizations thus pinpoint that the pHi regulatory effects on TMEM16F stem from the competition between Ca2+ and protons for the primary Ca2+-binding residues in the pore. Within the physiological [Ca2+]i range, the protonation state of the primary Ca2+-binding sites influences Ca2+ binding and regulates TMEM16F activation. Our findings thus uncover a regulatory mechanism of TMEM16F by pHi and shine light on our understanding of the pathophysiological roles of TMEM16F in diseases with dysregulated pHi, including cancer.
College Campuses and COVID-19 Mitigation: Clinical and Economic Value

Background Colleges in the United States are determining how to operate safely amid the coronavirus disease 2019 (COVID-19) pandemic. Objective To examine the clinical outcomes, cost, and cost-effectiveness of COVID-19 mitigation strategies on college campuses. Design The Clinical and Economic Analysis of COVID-19 interventions (CEACOV) model, a dynamic microsimulation model, was used to examine alternative mitigation strategies. The CEACOV model tracks infections accrued by students and faculty, accounting for community transmissions. Data sources Data from published literature were used to obtain parameters related to COVID-19 and contact-hours. Target population Undergraduate students and faculty at U.S. colleges. Time horizon One semester (105 days). Perspective Modified societal. Intervention COVID-19 mitigation strategies, including social distancing, masks, and routine laboratory screening. Outcome measures Infections among students and faculty per 5000 students and per 1000 faculty, isolation days, tests, costs, cost per infection prevented, and cost per quality-adjusted life-year (QALY). Results of base-case analysis Among students, mitigation strategies reduced COVID-19 cases from 3746 with no mitigation to 493 with extensive social distancing and masks, and further to 151 when laboratory testing was added among asymptomatic persons every 3 days. Among faculty, these values were 164, 28, and 25 cases, respectively. Costs ranged from about $0.4 million for minimal social distancing to about $0.9 million to $2.1 million for strategies involving laboratory testing ($10 per test), depending on testing frequency. Extensive social distancing with masks cost $170 per infection prevented ($49 200 per QALY) compared with masks alone. Adding routine laboratory testing increased cost per infection prevented to between $2010 and $17 210 (cost per QALY gained, $811 400 to $2 804 600). Results of sensitivity analysis Results were most sensitive to test costs. Limitation Data are from multiple sources. Conclusion Extensive social distancing with a mandatory mask-wearing policy can prevent most COVID-19 cases on college campuses and is very cost-effective. Routine laboratory testing would prevent 96% of infections and require low-cost tests to be economically attractive. Primary funding source National Institutes of Health.
ON-OFF Privacy Against Correlation Over Time

We consider the problem of ON-OFF privacy in which a user is interested in the latest message generated by one of $n$ sources available at a server. The user has the choice to turn privacy ON or OFF depending on whether he wants to hide his interest at the time or not. The challenge of allowing the privacy to be toggled between ON and OFF is that the user’s online behavior is correlated over time. Therefore, the user cannot simply ignore the privacy requirement when privacy is OFF. We represent the user’s correlated requests by an $n$ -state Markov chain. Our goal is to design ON-OFF privacy schemes with optimal download rate that ensure privacy for past and future requests. We devise a polynomial-time algorithm to construct an ON-OFF privacy scheme. Moreover, we present an upper bound on the achievable rate. We show that the proposed scheme is optimal and the upper bound is tight for some special families of Markov chains. We also give an implicit characterization of the optimal achievable rate as a linear programming (LP).
Synthesis of Axially Chiral 2,2'-Bisphosphobiarenes via a Nickel-Catalyzed Asymmetric Ullmann Coupling: General Access to Privileged Chiral Ligands without Optical Resolution.

We report an asymmetric homocoupling of ortho-(iodo)arylphosphine oxides and ortho-(iodo)arylphosphonates resulting in highly enantioenriched axially chiral bisphosphine oxides and bisphosphonates....
Multi-Agent Reinforcement Learning in Cournot Games

In this work, we study the interaction of strategic agents in continuous action Cournot games with limited information feedback. Cournot game is the essential market model for many socio-economic systems where agents learn and compete without the full knowledge of the system or each other. We consider the dynamics of the policy gradient algorithm, which is a widely adopted continuous control reinforcement learning algorithm, in concave Cournot games. We prove the convergence of policy gradient dynamics to the Nash equilibrium when the price function is linear or the number of agents is two. This is the first result (to the best of our knowledge) on the convergence property of learning algorithms with continuous action spaces that do not fall in the no-regret class.
Splitting the Difference: Layshock and J.S. Chart a Separate Path on Student Speech Rights

On June 13, 2011, the U.S. Court of Appeals for the Third Circuit, in Layshock ex rel. Layshock v. Hermitage School District and J.S. ex rel. Snyder v. Blue Mountain School District, held that school officials could not constitutionally punish the online, off-campus speech of two students when the speech would not foreseeably cause substantial disruption in school. Although the Third Circuit’s results in these cases were consistent with Second Circuit precedent, the Third Circuit employed a less restrictive method for analyzing limitations on student speech. Accordingly, this Comment argues that the standards applied by the Third Circuit will lead to decisions in future online, off-campus speech cases which will generally be more favorable to public school districts than similar cases in the Second Circuit.
Fixing the Fatal Flaws in OUI Implied Consent Laws

This Article explores the use of implied consent laws as a method of deterring and punishing alcohol-impaired driving. Part I introduces the history and purpose of implied consent laws. Part II discusses the inadequacies of current statutory implied consent provisions and their failure to effectively attain their designed purpose. This section also highlights two particularly detrimental aspects of the law as currently implemented: (1) the lack of uniformity in the application of the laws by individual states; and (2) the disparate treatment of persons who refuse to submit to BAC testing, both in terms of consequences of refusal to submit to testing and evidential use at trial. Ultimately, this Article espouses the notion that evidence of a defendant's BAC is one of the most valuable and persuasive pieces of evidence in an OUI case and is directly linked to the deterrence function of implied consent laws. BAC evidence may exonerate an individual who is wrongfully charged and may help to convict an individual who is impaired. By denying the prosecution the ability to collect and use this evidence, the likelihood of conviction is greatly reduced. Part III provides statutory guidance to ensure that implied consent laws are meaningful and powerful law enforcement tools that effectively achieve their stated purpose: a reduction in the number of intoxicated drivers on the highways. If a motorist refuses to provide a BAC sample, there should be a separate criminal charge rather than just an administrative penalty. Additionally, the prosecution should be permitted to present evidence to the fact-finder about the defendant's refusal to submit to BAC testing. When death or serious bodily injury results from a car crash, compulsory BAC testing must be administered to the operator. Furthermore, the administrative sanction for refusing to submit to the test should be harsher than the administrative sanction for testing over the legal limit. Finally, when an individual's license is suspended for a refusal, the license should only be reinstated after the entire suspension period is over. These changes to current statutory implied consent provisions are necessary; otherwise, implied consent in an OUI context is meaningless.
Rational Choice and Reasonable Interactions

Game theory offers us an account of how rational agents interact in strategic situations. The situations are strategic in that the determination of rational conduct for any one agent will depend upon what that agent believes another agent in the interaction might do. Of course, this other agent will also typically be working out her own strategy in light of the beliefs she has about the first agent and what the first agent might do. Thus, a rational agent needs to think not only about what to do, but also about what another agent is thinking about what to do and, further, about what that other agent is thinking about what the first agent is thinking about what to do. And so on. In non-cooperative game theory this thinking, while quite sophisticated, and having as its subject matter the thoughts and actions of another, remains very private. Each agent typically works out what to do, or how to interact with another, as a matter of private rationality. All of this is familiar. What is less familiar, perhaps, is that the law and legal theory also contain an account of how rational agents interact. However, it is an account of how rational agents interact, and how they understand their interaction, under the idea of public (or objective) reasonableness. More straightforwardly, we might say that law and legal theory offer an account of how “reasonable persons” interact. While this terminol-
Langdell and the Invention of Legal Doctrine

This paper addresses two related questions. The first relates to Langdell and his development of a doctrinal theory of contract law. The substance and method of Langdell’s work has not been well understood and this paper uses a variety of historical materials to remedy this problem. It begins with a review of contract law prior to Langdell. Contract law at this time was in a very primitive state. The available treatises were confusing and the cases themselves offered little guidance for predicting future case outcomes. The paper then proceeds to examine Langdell’s method by describing certain logic texts that describe the Nineteenth Century conception of scientific methodology. This enables us to recreate not only the substance of Langdell’s theory, but also its method. Further, understanding its method allows us to ask crucial questions about justification: What is it that makes Langdell believe that his theory of contract law is correct? The second question addressed in this paper relates to legal theory and the use of doctrinal theories in legal decision making. As a pragmatist, I reject the idea that there is one form of legal reasoning. Instead I believe that the courts employ a variety of strategies to navigate between the demand for justice in the individual case and the need to develop general theories that can be used to predict future decisions. Doctrinal theories are one of these strategies and, without question, a very important one. In the final section I use what we have learned about Langdell to identify the way in which doctrinal theories work and to explain their success.
The Value of Commitment with Imperfect Observability and Private Information

The idea that commitment is valuable plays a key role in many economic models. However, Bagwell (1995) has shown that commitment may have no value if there is (even a slight) noise in the observation of the leader's action, thus casting doubt on the notion that commitment has strategic value. Here I reconsider the commitment story in a model where the leader's action is imperfectly observed and the leader has private information, and I examine how it is affected by uncertainty about the leader's type and by the observation noise.
Food Security and Economic Growth: an Asian perspective

Food security is an elusive concept. Many economists doubt that it has any precise meaning at all. Having enough to eat on a regular basis, however, is a powerful human need, and satisfying this need drives household behavior in both private and public markets in predictable ways. Indeed, the historical record suggests that policy initiatives by central governments to satisfy this need for food security—at the level of both households and national markets—can speed economic growth in countries where a substantial proportion of the population does not get enough to eat. Paradoxically, in most successfully developing countries, especially those in the rice-based economies of Asia, the public provision of food security quickly slips from its essential role as an economic stimulus into a political response to the pressures of rapid structural transformation, thereby becoming a drag on economic efficiency. The long-run relationship between food security and economic growth thus tends to switch from positive to negative over the course of development. Because of inevitable inertia in the design and implementation of public policy, this switch presents a serious challenge to the design of an appropriate food policy. (This abstract was borrowed from another version of this item.)
Thinking Critically About How To Address Violence Against Women

Every day across the Americas, men, women, and children are forced to work in degrading circumstances due to structural poverty and inequality. They do not earn a living wage, and they are denied the opportunity to thrive to their fullest potential. They are often the victims of violence, sometimes perpetrated, often tolerated, by agents of the state. Life for these individuals is too often “poor, nasty, brutish, and short.” Women and girls are often subjected to the worst abuses. Across the developing world, they work more and are paid less. They receive inferior health care, less education, and they are more likely to be the victims of sexual violence. Women of color, women with disabilities, migrants, and gay, bisexual, lesbian and transgendered people often suf-
Real Options and Merchant Operations of Energy and Other Commodities

The value chain for energy and other commodities entails physical conversions through refineries, power plants, storage facilities, and transportation and other capital-intensive infrastructure. When the operation of such commodity conversion assets occurs alongside liquid markets for the input and output commodities, the operating flexibility of conversion assets can be managed as real options on the underlying commodity prices. Merchant operations is an integrated trading and operations approach that (i) buys and sells commodities to support market-value maximizing operating policies and (ii) values conversion assets, for capital budgeting and trading purposes, based on the cash flows such policies produce. This monograph provides a unique integrated finance and operations perspective on the topic of merchant operations. In particular, this monograph introduces the concept of merchant operations; presents the basic principles of option valuation; surveys foundational models of commodity and energy price evolution; analyzes the structure of optimal operating policies for commodity conversions, focusing specifically on inventory and other intertemporal linkages in storage, inventory acquisition and disposal, and swing assets; considers a variety of heuristic storage operating policies; and discusses future trends in this multidisciplinary area of research and business applications.
The Geography of Wage Discrimination in the Pre–Civil Rights South

Prior to the modern civil rights movement of the 1960s, the pay gap between African-American and white workers in the South was large overall, but also quite variable across location. Using 1940 census data, I estimate the white-black earnings gap of men for separate county groups called state economic areas, adjusting for individual differences in schooling and experience. I show that the gap was significantly greater in areas where, ceteris paribus, blacks were a larger proportion of the workforce, plantation institutions were more prevalent, more of the population was urban, and white voters exhibited segregationist preferences.
CAUSES OF THE FINANCIAL CRISIS

ABSTRACT Why did the popping of the housing bubble bring the financial system—rather than just the housing sector of the economy—to its knees? The answer lies in two methods by which banks had evaded regulatory capital requirements. First, they had temporarily placed assets—such as securitized mortgages—in off‐balance‐sheet entities, so that they did not have to hold significant capital buffers against them. Second, the capital regulations also allowed banks to reduce the amount of capital they held against assets that remained on their balance sheets—if those assets took the form of AAA‐rated tranches of securitized mortgages. Thus, by repackaging mortgages into mortgage‐backed securities, whether held on or off their balance sheets, banks reduced the amount of capital required against their loans, increasing their ability to make loans many‐fold. The principal effect of this regulatory arbitrage, however, was to concentrate the risk of mortgage defaults in the banks and render them insolvent when the ho...
Contagion of the eurozone debt crisis

Abstract This paper examines the contagion of the eurozone debt crisis to developed and emerging stock markets around the world. Using the VAR methodology, and changes in sovereign bond yields and stock returns of the crisis countries as proxies for the eurozone debt crisis, this paper finds strong and pervasive evidence of negative contagion from the crisis countries to other stock markets. Consistent with risk-on risk-off hypothesis, changes in sovereign bond yields of crisis countries impact stock returns positively during normal times and negatively during the crisis, providing strong evidence of negative contagion. The impact of equity returns of crisis countries on other equity markets is large and positive during normal times and less positive during the crisis, suggesting evidence of negative contagion and decoupling of stock markets during the crisis. The Asian markets do not show pervasive evidence of contagion from the eurozone crisis.
Re-Evaluating the Privileges or Immunities Clause

In its 1999 case, Saenz v. Roe, the Supreme Court re-invigorated a long-dead clause of the Constitution, the Privileges or Immunities Clause of the 14th Amendment. Oddly, though, the opinion was written by Justice Stevens, one of the staunchest devotees of a living Constitution rather than originalism. As odd: Justice Thomas, the most consistent originalist on the Court, was in dissent. In his view, any reinvigoration of the Privileges or Immunities Clause should displace, rather than augment, the untethered jurisprudence that expansively interpreted other clauses of the 14th Amendment to cover the neutered Privileges or Immunities Clause, and it should be revived as originally contemplated. This article begins to take up the invitation made by Justice Thomas to explore the original meaning of the Privileges or Immunities Clause, contending that it (and its sister clause in Article IV of the original Constitution) was one of the clauses actually designed to codify the basic natural rights principles of the Declaration of Independence.
Spin Control and Freedom of Information: Lessons for the United Kingdom from Canada

The United Kingdom's new Freedom of Information Act (FOIA) is intended to empower citizens by granting a right to government documents. However, the law will be implemented by a government that has developed highly centralized structures for controlling the communications activity of its departments. How will the revolutionary potential of the FOIA be squared with government's concern for ‘message discipline’? Experience in implementing Canada's Access to Information Act may provide an answer. The Canadian law was intended to constrain executive authority, but officials developed internal routines and technologies to minimize its disruptive potential. These practices restrict the right to information for certain types of stakeholders, such as journalists or representatives of political parties. The conflict between public expectations of transparency and elite concerns about governability may not be adequately accounted for during implementation of the UK Freedom of Information Act.