cssi/SciSciGPT-SciSciNet huggingface dataset:
The thermodynamics of thinking: connections between neural activity, energy metabolism and blood flow

Several current functional neuroimaging methods are sensitive to cerebral metabolism and cerebral blood flow (CBF) rather than the underlying neural activity itself. Empirically, the connections between metabolism, flow and neural activity are complex and somewhat counterintuitive: CBF and glycolysis increase more than seems to be needed to provide oxygen and pyruvate for oxidative metabolism, and the oxygen extraction fraction is relatively low in the brain and decreases when oxygen metabolism increases. This work lays a foundation for the idea that this unexpected pattern of physiological changes is consistent with basic thermodynamic considerations related to metabolism. In the context of this thermodynamic framework, the apparent mismatches in metabolic rates and CBF are related to preserving the entropy change of oxidative metabolism, specifically the O2/CO2 ratio in the mitochondria. However, the mechanism supporting this CBF response is likely not owing to feedback from a hypothetical O2 sensor in tissue, but rather is consistent with feed-forward control by signals from both excitatory and inhibitory neural activity. Quantitative predictions of the thermodynamic framework, based on models of O2 and CO2 transport and possible neural drivers of CBF control, are in good agreement with a wide range of experimental data, including responses to neural activation, hypercapnia, hypoxia and high-altitude acclimatization. This article is part of the theme issue 'Key relationships between non-invasive functional neuroimaging and the underlying neuronal activity'.
A thermodynamic theory of ecology: Helmholtz theorem for Lotka–Volterra equation, extended conservation law, and stochastic predator–prey dynamics

We carry out mathematical analyses, a la Helmholtz’s and Boltzmann’s 1884 studies of monocyclic Newtonian dynamics, for the Lotka–Volterra (LV) equation exhibiting predator–prey oscillations. In doing so, a novel ‘thermodynamic theory’ of ecology is introduced. An important feature, absent in the classical mechanics, of ecological systems is a natural stochastic population dynamic formulation of which the deterministic equation (e.g. the LV equation studied) is the infinite population limit. Invariant density for the stochastic dynamics plays a central role in the deterministic LV dynamics. We show how the conservation law along a single trajectory extends to incorporate both variations in a model parameter α and in initial conditions: Helmholtz’s theorem establishes a broadly valid conservation law in a class of ecological dynamics. We analyse the relationships among mean ecological activeness θ , quantities characterizing dynamic ranges of populations A and α , and the ecological force F α . The analyses identify an entire orbit as a stationary ecology, and establish the notion of an ‘equation of ecological states’. Studies of the stochastic dynamics with finite populations show the LV equation as the robust, fast cyclic underlying behaviour. The mathematical narrative provides a novel way of capturing long-term dynamical behaviours with an emergent conservative ecology .
Decentralized Sequential Composite Hypothesis Test Based on One-Bit Communication

This paper considers the sequential composite hypothesis test with multiple sensors. The sensors observe random samples in parallel and communicate with a fusion center, who makes the global decision based on the sensor inputs. On the one hand, in the centralized scenario, where local samples are precisely transmitted to the fusion center, the generalized sequential likelihood ratio test (GSPRT) is shown to be asymptotically optimal in terms of the expected sample size as error rates tend to zero. On the other hand, for systems with limited power and bandwidth resources, decentralized solutions that only send a summary of local samples (we particularly focus on a one-bit communication protocol) to the fusion center is of great importance. To this end, we first consider a decentralized scheme where sensors send their one-bit quantized statistics every fixed period of time to the fusion center. We show that such a uniform sampling and quantization scheme is strictly suboptimal and its suboptimality can be quantified by the KL divergence of the distributions of the quantized statistics under both the hypotheses. We then propose a decentralized GSPRT based on level-triggered sampling. That is, each sensor runs its own GSPRT repeatedly and reports its local decision to the fusion center asynchronously. We show that this scheme is asymptotically optimal as the local thresholds and global thresholds grow large at different rates. Finally, two particular models and their associated applications are studied to compare the centralized and decentralized approaches. Numerical results are provided to demonstrate that the proposed level-triggered sampling based decentralized scheme aligns closely with the centralized scheme with substantially lower communication overhead, and significantly outperforms the uniform sampling and quantization-based decentralized scheme.
A quantitative analysis of IRAS maps of molecular clouds

We present an analysis of IRAS maps of five molecular clouds: Orion, Ophiuchus, Perseus, Taurus, and Lupus. For the classification and description of these astrophysical maps, we use a newly developed technique which considers all maps of a given type to be elements of a pseudometric space. For each physical characteristic of interest, this formal system assigns a distance function (a pseudometric) to the space of all maps: this procedure allows us to measure quantitatively the difference between any two maps and to order the space of all maps. We thus obtain a quantitative classification scheme for molecular clouds. In this present study we use the IRAS continuum maps at 100 and 60 micrometer(s) to produce column density (or optical depth) maps for the five molecular cloud regions given above. For this sample of clouds, we compute the 'output' functions which measure the distribution of density, the distribution of topological components, the self-gravity, and the filamentary nature of the clouds. The results of this work provide a quantitative description of the structure in these molecular cloud regions. We then order the clouds according to the overall environmental 'complexity' of these star-forming regions. Finally, we compare our results with the observed populations of young stellar objects in these clouds and discuss the possible environmental effects on the star-formation process. Our results are consistent with the recently stated conjecture that more massive stars tend to form in more 'complex' environments.
Two-Scale Structure for Giant Field Enhancement: Combination of Rayleigh Anomaly and Colloidal Plasmonic Resonance

Author(s): Darvishzadeh-Varcheie, M; Thrift, WJ; Kamandi, M; Ragan, R; Capolino, F | Abstract: We propose a two-scale architecture by simultaneously exploiting both the Rayleigh anomaly and localized surface plasmon resonance in colloidal directly assembled oligomers to achieve giant field enhancement, overcoming limitations by losses and the intrinsic nonlocality of the dielectric response of metal nanoparticles. We show that the total field enhancement in the nanogap hotspots of this two-scale structure is the product of the enhancements of each individual geometrical scale. Under this scheme, chemically assembled metallic oligomers enable strong enhancement of the near-field in resultant few-nanometer gaps at their plasmonic resonance. An extra enhancement factor results from combining the plasmonic resonance enhancement of these oligomers (nanometer scale) with a Rayleigh anomaly caused by a one-dimensional (1D) periodic set of nanorods (micrometer scale) fabricated using a lithographic method. This extra field enhancement cannot be obtained by further reducing the nanoantennas' gaps, since they are already in the few-nm ranges thanks to direct chemical assembly of oligomers. Experimental results verify that surface-enhanced Raman spectroscopy (SERS) signal is enhanced by more than one order of magnitude due to the Rayleigh anomaly as compared to the signal taken by using only metallic oligomers without periodic nanorods. The proposed two-scale structure could serve as a substrate for different spectroscopy techniques including SERS and can improve the sensitivity of spectroscopy for ultrasensitive biomolecule detection and single molecule spectroscopy studies.
Population Games and Discrete Optimal Transport

We propose an evolutionary dynamics for population games with discrete strategy sets, inspired by optimal transport theory and mean field games. The proposed dynamics is the Smith dynamics with strategy graph structure, in which payoffs are modified by logarithmic terms. The dynamics can be described as a Fokker–Planck equation on a discrete strategy set. For potential games, the dynamics is a gradient flow system under a Riemannian metric from optimal transport theory. The stability of the dynamics is studied through optimal transport metric tensor, free energy and Fisher information.
FIRST 0747+2739: A FIRST/2MASS Quasar with an Overabundance of C IV Absorption Systems

We present a Keck Observatory/Echelle Spectrograph and Imager spectrum of FIRST 074711.2+273904, a K = 15.4 quasar with a redshift of 4.11 that is detected by both the Faint Images of the Radio Sky at Twenty cm (FIRST) survey and the Two Micron All Sky Survey (2MASS). The spectrum contains at least 14 independent C IV absorption systems longward of the Lyα forest. These systems are found over a path length of Δz = 0.984, constituting one of the highest densities per unit redshift of C IV absorption ever observed. One of the C IV systems is troughlike and resembles a weak broad absorption line (BAL)-type outflow. Two of the C IV are "associated" absorption systems with |v| 3000 km s-1, eight are either resolved or require multiple discrete systems to fit the line profiles. In addition to C IV absorption, there are two low-ionization Mg II absorption systems, along with two damped Lyα systems, at least one of which may be a C IV system. The overdensity of C IV absorption spans a redshift range of Δz ~ 1. Superclusters along the line of sight are unlikely to cause an overdensity stretching over such a long redshift path; thus, the absorption may be an example of narrow, high-velocity intrinsic absorption that originates from the quasar. We suggest that this quasar is a member of a transitional class of BAL quasars, where we are just barely seeing the spatial, density, or temporal edge of the BAL-producing region (or period); the multiple high-velocity absorption systems may be the remnants (or precursors) of a stronger BAL outflow. If correct, then some simpler absorption-line complexes in other quasars may also be due to outflowing rather than to intervening material.
Long-Time Predictive Modeling of Nonlinear Dynamical Systems Using Neural Networks

We study the use of feedforward neural networks (FNN) to develop models of nonlinear dynamical systems from data. Emphasis is placed on predictions at long times, with limited data availability. Inspired by global stability analysis, and the observation of strong correlation between the local error and the maximal singular value of the Jacobian of the ANN, we introduce Jacobian regularization in the loss function. This regularization suppresses the sensitivity of the prediction to the local error and is shown to improve accuracy and robustness. Comparison between the proposed approach and sparse polynomial regression is presented in numerical examples ranging from simple ODE systems to nonlinear PDE systems including vortex shedding behind a cylinder and instability-driven buoyant mixing flow. Furthermore, limitations of feedforward neural networks are highlighted, especially when the training data does not include a low dimensional attractor. Strategies of data augmentation are presented as remedies to address these issues to a certain extent.
Spin of the M87 Black Hole

Spin measurement of the 6.5 billion solar mass black hole in M87 from the Event Horizon Telescope image is the latest in a series that span a wide range in values, but that tend to share the feature of co-rotation between the accretion flow and black hole. The spin paradigm for black holes predicts very high black hole spin which in that framework was produced in its last significant merger. High black hole spin appears to be ruled out in the gap paradigm, however, which predicts early formation with a mass already in excess of 4 billion solar masses. In this picture, the black hole experienced slow evolution as it departed from its original radio quasar phase and over billions of years not only failed to double its mass but also fell short of regaining its original high spin, such that it is now compatible with a co-rotating accreting black hole whose dimensionless spin fits best in the range 0.2 < a < 0.5.
Survey of End-to-End Mobile Network Measurement Testbeds, Tools, and Services

Mobile (cellular) networks enable innovation, but can also stifle it and lead to user frustration when network performance falls below expectations. As mobile networks become the predominant method of Internet access, developer, research, network operator, and regulatory communities have taken an increased interest in measuring end-to-end mobile network performance to, among other goals, minimize negative impact on application responsiveness. In this survey, we examine current approaches to end-to-end mobile network performance measurement, diagnosis, and application prototyping. We compare available tools and their shortcomings with respect to the needs of developers, researchers, network operators, and regulators. We intend for this survey to provide a comprehensive view of currently active efforts and some auspicious directions for future work in mobile network measurement and mobile application performance evaluation.
Simulations of ion acceleration at non-relativistic shocks. II. Magnetic field amplification

We use large hybrid simulations to study ion acceleration and generation of magnetic turbulence due to the streaming of particles that are self-consistently accelerated at non-relativistic shocks. When acceleration is efficient, we find that the upstream magnetic field is significantly amplified. The total amplification factor is larger than 10 for shocks with Alfvenic Mach number M = 100, and scales with the square root of M. The spectral energy density of excited magnetic turbulence is determined by the energy distribution of accelerated particles, and for moderately strong shocks (M ≲ 30) agrees well with the prediction of resonant streaming instability, in the framework of quasilinear theory of diffusive shock acceleration. For M ≳ 30, instead, Bell's non-resonant hybrid (NRH) instability is predicted and found to grow faster than resonant instability. NRH modes are excited far upstream by escaping particles, and initially grow without disrupting the current, their typical wavelengths being much shorter than the current ions' gyroradii. Then, in the nonlinear stage, most unstable modes migrate to larger and larger wavelengths, eventually becoming resonant in wavelength with the driving ions, which start diffuse. Ahead of strong shocks we distinguish two regions, separated by the free-escape boundary: the far upstream, wheremore » field amplification is provided by the current of escaping ions via NRH instability, and the shock precursor, where energetic particles are effectively magnetized, and field amplification is provided by the current in diffusing ions. The presented scalings of magnetic field amplification enable the inclusion of self-consistent microphysics into phenomenological models of ion acceleration at non-relativistic shocks.« less
Minimal pseudo-Anosov translation lengths on the complex of curves

We establish bounds on the minimal asymptotic pseudo-Anosov translation lengths on the complex of curves of orientable surfaces. In particular, for a closed surface with genus g ≥ 2, we show that there are positive constants a1 < a2 such that the minimal translation length is bounded below and above by a1∕g2 and a2∕g2.
Asymptotics of a class of Weil–Petersson geodesics and divergence of Weil–Petersson geodesics

We show that the strong asymptotic class of Weil-Petersson (WP) geodesics with narrow end invariant and bounded annular coefficients is determined by the forward ending lamination. This generalizes the Recurrent Ending Lamination Theorem of Brock-Masur-Minsky. As an application we provide a symbolic condition for divergence of WP geodesic rays in the moduli space.
ENTROPY PRODUCTION IN COLLISIONLESS SYSTEMS. I. LARGE PHASE-SPACE OCCUPATION NUMBERS

Certain thermal non-equilibrium situations, outside of the astrophysical realm, suggest that entropy production extrema, instead of entropy extrema, are related to stationary states. In an effort to better understand the evolution of collisionless self-gravitating systems, we investigate the role of entropy production and develop expressions for the entropy production rate in two particular statistical families that describe self-gravitating systems. From these entropy production descriptions, we derive the requirements for extremizing the entropy production rate in terms of specific forms for the relaxation function in the Boltzmann equation. We discuss some implications of these relaxation functions and point to future work that will further test this novel thermodynamic viewpoint of collisionless relaxation.
CIRCUMSTELLAR DUST AROUND AGB STARS AND IMPLICATIONS FOR INFRARED EMISSION FROM GALAXIES

Stellar population synthesis (SPS) models are used to infer many galactic properties including star formation histories, metallicities, and stellar and dust masses. However, most SPS models neglect the effect of circumstellar dust shells around evolved stars and it is unclear to what extent they impact the analysis of spectral energy distributions (SEDs). To overcome this shortcoming we have created a new set of circumstellar dust models, using the radiative transfer code DUSTY, for asymptotic giant branch (AGB) stars and incorporated them into the Flexible Stellar Population Synthesis code. The circumstellar dust models provide a good fit to individual AGB stars as well as the IR color–magnitude diagrams of the Large and Small Magellanic Clouds. IR luminosity functions from the Large and Small Magellanic Clouds are not well-fit by the 2008 Padova isochrones when coupled to our circumstellar dust models and so we adjusted the lifetimes of AGB stars in the models to provide a match to the data. We show, in agreement with previous work, that circumstellar dust from AGB stars can make a significant contribution to the IR () emission from galaxies that contain relatively little diffuse dust, including low-metallicity and/or non-star-forming galaxies. Our models provide a good fit to the mid-IR spectra of early-type galaxies. Circumstellar dust around AGB stars appears to have a small effect on the IR SEDs of metal-rich star-forming galaxies (i.e., when AV ≳ 0.1). Stellar population models that include circumstellar dust will be needed to accurately interpret data from the James Webb Space Telescope and other IR facilities.
Large N BPS states and emergent quantum gravity

This paper provides a heuristic derivation of how classical gravitational physics in the AdS/CFT correspondence appears from the strong dynamics of the N = 4 SYM theory in a systematic way. We do this in a minisuperspace approximation by studying 1/8 BPS configurations. We can show that our description matches the semiclassical physics of 1/8 BPS states in supergravity. We also provide a heuristic description of how massive strings appear in the geometry, and how at strong 't Hooft coupling they become local on the S 5 suggesting that they can be realized as a sigma model on a weakly curved background. We show that the dynamics of 1/8 BPS dynamics of N = 4 SYM on a round S 3 can be reduced to that of a matrix model for commuting matrices. Including measure factors, we show that this effective dynamics is related to bosons living on a six dimensional phase space with repulsive interactions. Because of these interactions, we can argue that on the ground state the bosons assemble themselves on a spherical shell in the shape of a round five sphere. This sphere will be identified with the S 5 in the AdS dual geometry. To do this, we first define a precise way to coarse grain the dynamics. We use half BPS configurations as a toy model for this coarse graining, and we can reproduce the droplet picture of these half BPS states systematically. The droplet appears as the saddle point approximation of a statistical ensemble related to the square of the wave function of the eigenvalues of a complex matrix. This procedure is also applied to the set of 1/8 BPS configurations to extract the geometry, giving an analog of the droplet picture of half BPS states for the case of 1/8 BPS configurations. We also have a conjectured realization of some 1/8 BPS giant graviton wave functions in the dynamics, which captures all 1/8 BPS giant gravitons constructed by Mikhailov. This leads to a lot of different topology changes which can be treated heuristically.
Computational Modeling of Attentional Impairments in Disruptive Mood Dysregulation and Attention-Deficit/Hyperactivity Disorder.

Objective Computational models provide information about cognitive components underlying behavior. When applied to psychopathology-relevant processes, they offer additional insight to observed differences in behavioral performance. Drift diffusion models have been successfully applied to investigate processing efficiency during binary choice tasks. Using these models, we examine the association between psychopathology (irritability and inattention/hyperactivity) and processing efficiency under different attentional demands. Method A total of 187 youths with attention-deficit/hyperactivity disorder (ADHD), disruptive mood dysregulation disorder (DMDD), both disorders, or no major psychopathology (age, mean ± SD, 13.09 ± 2.55 y, 34% female) completed an Eriksen Flanker task. Of these, 87 youths provided complete data on dimensional measures of the core symptom of DMDD (irritability) and those of ADHD (inattention and hyperactivity). Results In a categorical diagnosis-based analysis (n = 187), we found significant interactive effects among ADHD, DMDD, and task condition on processing efficiency, whereby changes in processing efficiency between conflict and nonconflict conditions were larger in youths without psychopathology compared with patients. Analysis of symptom severity (n = 87) across diagnoses similarly revealed an interaction between symptom dimensions and task condition on processing efficiency. Irritability moderated the magnitude of association between inattention symptoms and difference in processing efficiency between conflict and nonconflict conditions. Conclusion Adapting processing efficiency to cognitive demands may represent a shared cognitive endophenotype for both ADHD and DMDD. Highly irritable and/or inattentive youth may have difficulty adjusting processing efficiency to changing task demands, possibly reflecting impairments in cognitive flexibility.
Enhancing College and Career Readiness Programs for Underserved Adolescents

Supporting college and career readiness among youth who encounter significant academic and life challenges requires innovative strategies to help them envision their futures, leverage their strengths and develop dispositions that promote positive trajectories. For youth development professionals who develop and implement novel programmatic approaches to support the college and career readiness of underserved youth, it is critical to acquire a deeper evidence-based understanding of factors shaping positive career and college pathways as well as to incorporate stakeholder viewpoints in their program design and delivery. In this article, we share key insights from our program development process that can inform the work of program developers, educators and youth services providers who seek to build and enhance career and college readiness programs aimed at underserved youth. We summarize 4 key insights from a narrative review of literature on college and career readiness as well as findings from a set of stakeholders (student, parent and educator) focus groups. We offer our ideas for incorporating these insights alongside stakeholder input into the development and design of college and career readiness activities and programming.
LIFTED: Household Appliance-level Load Dataset and Data Compression with Lossless Coding considering Precision

The issue of estimating the detailed appliance-level load consumption has received considerable attention. This paper first presents a Labelled hIgh Frequency daTaset for Electricity Disaggregation (LIFTED), which can be used for research on nonintrusive load monitoring (NILM). This dataset consists of one-week detailed appliance-level electricity usage information including voltage, current, active power, and reactive power for a single apartment in the United States, down-sampled at 50Hz. This paper also proposes an efficient Lossless Coding considering Precision (LCP) algorithm on data compression. This algorithm considers both the precision requirements of practical applications on load datasets and the unique characteristics of household appliance-level load datasets. The LCP algorithm is tested on the LIFTED and REDD dataset and the results demonstrate that LCP can achieve higher compression ratio compared to several existing algorithms.
egg: Fast and extensible equality saturation

An e-graph efficiently represents a congruence relation over many expressions. Although they were originally developed in the late 1970s for use in automated theorem provers, a more recent technique known as equality saturation repurposes e-graphs to implement state-of-the-art, rewrite-driven compiler optimizations and program synthesizers. However, e-graphs remain unspecialized for this newer use case. Equality saturation workloads exhibit distinct characteristics and often require ad-hoc e-graph extensions to incorporate transformations beyond purely syntactic rewrites. This work contributes two techniques that make e-graphs fast and extensible, specializing them to equality saturation. A new amortized invariant restoration technique called rebuilding takes advantage of equality saturation's distinct workload, providing asymptotic speedups over current techniques in practice. A general mechanism called e-class analyses integrates domain-specific analyses into the e-graph, reducing the need for ad hoc manipulation. We implemented these techniques in a new open-source library called egg. Our case studies on three previously published applications of equality saturation highlight how egg's performance and flexibility enable state-of-the-art results across diverse domains.
Control of Unknown Nonlinear Systems with Linear Time-Varying MPC

We present a Model Predictive Control (MPC) strategy for unknown input-affine nonlinear dynamical systems. A non-parametric method is used to estimate the nonlinear dynamics from observed data. The estimated nonlinear dynamics are then linearized over time-varying regions of the state space to construct an Affine Time-Varying (ATV) model. Error bounds arising from the estimation and linearization procedure are computed by using sampling techniques. The ATV model and the uncertainty sets are used to design a robust Model Predictive Controller (MPC) which guarantees safety for the unknown system with high probability. A simple nonlinear example demonstrates the effectiveness of the approach where commonly used estimation and linearization methods fail.
The Virtues of Automated Vehicle Safety - Mapping Vehicle Safety Approaches to Their Underlying Ethical Frameworks

The safety of automated vehicles is principally a question of ethics. As a result, an understanding of the ethical frameworks that underlie different regulatory, legal and engineering approaches to vehicle safety can help to pinpoint potential challenges. Approaches that stem from deontological thinking can create a trap by requiring an exhaustive set of rules. In contrast, approaches that take a consequentialist perspective can create a perceived need to find an optimal solution. A framework based on virtue ethics, as developed further in this paper, avoids both of these traps, relying on engineering judgement and moral wisdom to extrapolate from core virtues towards practical solutions.
A Safety Constrained Control Framework for UAVs in GPS Denied Environment

Unmanned aerial vehicles (UAVs) suffer from sensor drifts in GPS denied environments, which can lead to potentially dangerous situations. To avoid intolerable sensor drifts in the presence of GPS spoofing attacks, we propose a safety constrained control framework that adapts the UAV at a path re-planning level to support resilient state estimation against GPS spoofing attacks. The attack detector is used to detect GPS spoofing attacks and provides a switching criterion between the robust control mode and emergency control mode. An attacker location tracker (ALT) is developed to track the attacker’s location and estimate the spoofing device’s output power by the unscented Kalman filter (UKF) with sliding window outputs. Using the estimates from ALT, we design an escape controller (ESC) based on the model predictive controller (MPC) such that the UAV escapes from the effective range of the spoofing device within the escape time.
Understanding and Contributing to the Enigma of Corporate Social Responsibility (CSR) Assurance in the United States

SUMMARY: This paper provides an empirical examination of the corporate social responsibility (CSR) assurance market in the United States. Various constituencies have found this market puzzling, as the level of assurance significantly lags international levels (Simnett et al. 2009; KPMG 2011). Results shed light on this enigma by demonstrating that, unlike their international counterparts, U.S. finance and utilities firms are not more likely (than firms in other industries) to obtain CSR assurance despite facing significant social and environmental risks. As these industries are highly regulated in the United States, regulatory oversight may be acting as a substitute for CSR assurance. We also find that highly leveraged firms are less likely to obtain CSR assurance, potentially due to stringent bank monitoring indirectly suppressing demand. Nonetheless, examining the capital market responses to CSR assurance makes the low demand even more puzzling. Specifically, CSR assurance is associated with lower cost...
Federal Interventions in Private Enterprise in the United States: Their Genesis in and Effects on Corporate Finance Instruments and Transactions

Over the past few years, in response to an international financial meltdown, state governments intervened in economies all over the world. As a result, government and business are interconnected in more numerous ways than perhaps ever before. Governments have increased their regulatory control over businesses in financial services and other sectors; businesses assist governments in implementing regulation; and governments are directly and indirectly engaged in financing businesses that had been conducted through nongovernmental entities. The United States exemplifies this new public-private archetype. [E]ven as the . . . paradigm semi-nationalized some traditional private financial services in the United States, it also contributed to the privatization of government functions, which, during this period, were in many ways “run like a business” rather than as a
Multilateral Contracting with Externalities

This paper proposes a model for multilateral contracting, where contracts are written and renegotiated over time, and where contracts may impose externalities on other agents. Equilibria always exist and the equilibrium value function is linear and monotonically increasing on the contracts. If the grand coalition, or contracting among all agents, is inefficient, we show that bargaining delays arise in positive-externality games and equilibrium inefficiency may remain bounded away from zero even as bargaining frictions converge to zero. Otherwise, if the grand coalition is efficient, there are no bargaining delays, convergence to the grand coalition occurs in a finite number of contracting rounds, and the outcome becomes efficient as players become more patient.
Firm Characteristics, Consumption Risk, and Firm-Level Risk Exposures

Abstract We propose a novel approach to measuring firm-level risk exposures and costs of equity. Using a simple consumption-based asset pricing model that explains nearly two-thirds of the variation in average returns across 55 anomaly portfolios, we map the relation between exposures to consumption risk and portfolio-level characteristics. We use this relation to calculate exposures to consumption risk at the firm level and show that the calculated consumption risk exposures yield portfolios with large differences in average returns and ex post consumption risk exposures consistent with those predicted by our calculated betas. Further, industry betas and risk premia implied by our procedure display economically intuitive variation over time. Finally, Fama-MacBeth regressions suggest that risk exposures calculated using our procedure dominate those from alternative factor models at explaining cross-sectional variation in returns.
The Role of the Internal Audit Function in the Disclosure of Material Weaknesses

ABSTRACT: This study investigates the role that a firm’s internal audit function (IAF) plays in the disclosure of material weaknesses reported under Section 404 of the Sarbanes-Oxley Act of 2002 (U.S. Congress 2002). Using data from 214 firms, we examine the relation between material weakness (MW) disclosures and various IAF attributes and activities. Our results indicate that MW disclosures are negatively associated with the education level of the IAF and the extent to which the IAF incorporates quality assurance techniques into fieldwork, audits activities related to financial reporting, and monitors the remediation of previously identified control problems. The timing of Section 404 work and the nature of follow-up monitoring suggests that these aspects of IAF quality help prevent MWs from occurring. We find that MW disclosures are positively associated with the IAF practice of grading audit engagements and external-internal auditor coordination, suggesting that these activities increase the effectiven...
Race Matters in Adoption

ignored. The findings and recommendations of the May 2008 Evan B. Donaldson Adoption Institute paper, Finding Families for African American Children: The Role of Race & Law in Adoption from Foster Care,2 are reviewed in section III. I discuss the current Child Welfare League of America's (CWLA) CWLA Standards of Excellence for Adoption Services3?the lens through which the Adoption Institute assessed the efficacy of current federal laws in section IV and V. I con clude this essay by urging members of the family law bar to endorse the Adoption Institute study recommendations and to work for their expedi tious implementations.
Diversification Across Time

Young people who buy stock on margin and reduce their equity exposure as they age can reduce lifetime portfolio risk. For example, an initially leveraged portfolio produces the same mean accumulation as a constant 74% stock allocation with a 21% smaller standard deviation. Since the means are equal, the reduced volatility doesn’t depend on the equity premium. A leveraged life-cycle strategy also lets investors come closer to their utility-maximizing equity allocation. Monte Carlo simulations show that the gains continue even with equity premiums well below historical levels.
The heterogeneity of the value of statistical life: Introduction and overview

The refinement in worker fatality risk data used in hedonic wage studies and evidence from new stated preference studies have facilitated the exploration of the heterogeneity of the value of statistical life (VSL). Although the median VSL estimate for workers is $7–$8 million, the VSL varies considerably within the worker population. New estimates of the income elasticity of VSL are 1.0 or above, which are consistent with theoretical models linking VSL to the coefficient of relative risk aversion. The specific relationship between VSL and risk aversion is, however, more complex than previously understood. Age differences in VSL are substantial, with young children being accorded especially high VSL amounts. The public’s willingness to pay to reduce risks is reduced if those being protected are perceived as being blameworthy due to their responsibility for contributing to the risk.
Synthetic depth-of-field with a single-camera mobile phone

Shallow depth-of-field is commonly used by photographers to isolate a subject from a distracting background. However, standard cell phone cameras cannot produce such images optically, as their short focal lengths and small apertures capture nearly all-in-focus images. We present a system to computationally synthesize shallow depth-of-field images with a single mobile camera and a single button press. If the image is of a person, we use a person segmentation network to separate the person and their accessories from the background. If available, we also use dense dual-pixel auto-focus hardware, effectively a 2-sample light field with an approximately 1 millimeter baseline, to compute a dense depth map. These two signals are combined and used to render a defocused image. Our system can process a 5.4 megapixel image in 4 seconds on a mobile phone, is fully automatic, and is robust enough to be used by non-experts. The modular nature of our system allows it to degrade naturally in the absence of a dual-pixel sensor or a human subject.
Decision-making by children

In this paper, we examine the determinants of decision-making power by children and young adolescents. Moving beyond previous economic models that treat children as goods consumed by adults, we develop a noncooperative model of parental control of child behavior and child resistance. Using child reports of decision-making and psychological and cognitive measures from the NLSY79 Child Supplement, we examine the determinants of shared and sole decision-making based on indices created from seven domains of child activity. We find that the determinants of sole decision-making by the child and shared decision-making with parents are quite distinct: sharing decisions appears to be a form of parental investment in child development rather than a simple stage in the transfer of authority. In addition, we find that indicators of child capabilities and preferences affect reports of decision-making authority in ways that suggest child demand for autonomy as well as parental discretion in determining these outcomes.
Derivatives traders' reaction to mispricing in the underlying equity

This article examines trading behavior in the options market conditioned on mispricing in the underlying stock. We investigate the price equilibrium between the observed equity asset and the options-implied synthetic share as well as the relative divergence between the two prices. We find a consistently positive relation between the level of stock mispricing and violations of the upper-boundary condition using derivatives, along with an increase in price divergence. To control for the effect of shorting limitations on mispricing, we further examine prices during the short-sale ban in 2008. The results hold and in many instances are more significant during the ban period. Given the persistent disequilibria between the synthetic and observed stock prices, we argue the results are evidence of informed trading in the derivatives market.
A New Era in High-energy Physics

In TeV-scale gravity, scattering of particles with center-of-mass energy of the order of a few TeV can lead to the creation of nonperturbative, extended, higher-dimensional gravitational objects: Branes. Neutral or charged, spinning or spinless, Einsteinian or supersymmetric, low-energy branes could dramatically change our picture of high-energy physics. Will we create branes in future particle colliders, observe them from ultra high energy cosmic rays, and discover them to be dark matter?
Public Economics and Inequality: Uncovering Our Social Nature

This paper argues that the social nature of humans, absent from the standard economic model, is crucial to understand our large modern social states and why concerns about inequality are so pervasive. A social solution arises when a situation is resolved at the group level (rather than the individual level) through cooperation and fair distribution of the resulting surplus. In human societies, childcare and education for the young, retirement benefits for the old, health care for the sick, and income support for those in need, is resolved at the social level, and through the social state in advanced economies. Social situations are pervasive even outside government and play a significant role in the distribution of pre-tax market incomes.
Insider trading and the long-run performance of new security issues

Abstract This paper uses insider trading around new security issues to provide evidence of managerial timing ability. I show that insider sales increase and purchases decrease prior to issues of information-sensitive securities (convertible debt and equity) by industrial firms. I then examine the relation between insider trading and subsequent stock returns. Although not all equity issues are motivated by overvaluation, those where managers sell prior to the issue are more likely to be. I find that industrial firms with abnormal insider selling underperform in the long run, whereas those with abnormal buying do not. There is no evidence of a relation between abnormal selling and future performance for utility offerings, however. Overall, the evidence is consistent with poor long-term performance being due to overvaluation.
Subsequent Practice and Evolutive Interpretation: Techniques of Treaty Interpretation over Time and Their Diverse Consequences

This paper compares two different means of treaty interpretation by which a treaty or treaty provision may change over time: the interpretation and reinterpretation of a treaty on the basis of its evolutive character, and the (re)interpretation of a treaty on the basis of the subsequent practice of the parties. I contend that evolutive interpretation and interpretation based on subsequent practice do not simply refer to two different and distinct phenomena ‐ as a practical matter they constitute two different “techniques of interpretation” which may or may not both be applicable in a particular case, and may sometimes both be applicable but mutually exclusive. The basic problem of the paper revolves around the following question: where the evidence is uncertain, or ambivalent, which technique ‐ if any ‐ should be applied? My goal is to show that although both techniques may be applicable to a treaty in a given case, the application of one or the other doctrine will have different consequences in the short and long term. In so doing, I will first expound the immediate effects of the techniques by examining them individually with an eye to their evidentiary criteria and their relative expansive potentialities. I shall then illustrate and compare their respective long term consequences, which I categorize as “vertical” (with respect to successive interpretations of the particular treaty in question) and “horizontal” (referring to effects on the interpretation of other treaties). Ultimately, I want to argue that neither means of interpretation is more appropriate across the board, and therefore the choice between the two techniques should be informed by the consideration of their consequences in light of the object and purpose of the particular treaty to be interpreted.
Revisiting location efficiency: strategies to graduate thinking on mortgage policy

ABSTRACTIn recent years, mortgage credit has become scarce, especially for low-to-middle income (LMI) individuals, including the working class and minorities. This has limited the ability of many of these individuals to purchase in sustainable, transportation accessible urban locations. This paper explores location efficient mortgages (LEM), their effectiveness in encouraging home ownership in highly connected urban locations with access to non-motorized transportation, and their viability in urban markets in the US. Cases are evaluated using inferential and descriptive statistics to evaluate potential opportunities for LEMs and building on these cases, additional strategies are suggested and discussed that could increase the efficacy of LEM tools. These included: 1) integration of shared responsibility LEMs; 2) utilizing local tax structures; and 3) exploring community-based finance programs. These tools could be useful in allowing LMI buyers purchase in sustainable and high-cost, urban environments.
Air quality and early-life mortality: Evidence from Indonesia's wildfires

Smoke from massive wildfires blanketed Indonesia in late 1997. This paper examines the impact that this air pollution (particulate matter) had on fetal, infant, and child mortality. Exploiting the sharp timing and spatial patterns of the pollution and inferring deaths from "missing children" in the 2000 Indonesian Census, I find that the pollution led to 15,600 missing children in Indonesia (1.2 percent of the affected birth cohorts). Prenatal exposure to pollution drives the result. The effect size is much larger in poorer areas, suggesting that differential effects of pollution contribute to the socioeconomic gradient in health.
Reverberations of the Victim's "Voice": Victim Impact Statements and the Cultural Project of Punishment

INTRODUCTION 1247 I. THE VICTIM IMPACT STATEMENT AND PUNISHMENT 1251 II. THE VICTIM IMPACT STATEMENT AS A NARRATIVE OF SUFFERING 1256 A. LAW AND NARRATIVE: AN OVERVIEW 1257 B. THE NARRATIVE STRUCTURE OF PAIN 1260 C. THE VICTIM IN HER OBJECT-RELATIONSHIP TO THE COURT 1272 III. CRIMINAL LAW AS A CULTURAL PRODUCT 1277 A. THE NOTION OF COMMUNAL HARM 1277 B. INDIVIDUAL AND CULTURAL MEMORY OF CRIME 1281 CONCLUSION 1285
Death in Our Life

This is the text of the Annual Lecture of the Society for Applied Philosophy, delivered in Oxford on 22-5-12. I kept the talk style of the paper. It examines a central aspect of the relations between duration and quality of life by considering the moral right to voluntary euthanasia, and some aspects of the moral case for a legal right to euthanasia. Would widespread acceptance of a right to voluntary euthanasia lead to widespread changes in attitude to life and death? Many of its advocates deny that seeing it as a narrow right enabling people to avoid ending their life in great pain or total dependence, or a vegetative state. I argue that the right cannot cogently be conceived as a narrow right, confined to very limited circumstances. It is based on the value of having the normative power to choose time and manner of one’s death. Its recognition will be accompanied by far reaching changes in culture and attitude, and these changes will enrich people’s life by enabling them to integrate their death as part of their lives.
A quantitative analysis of disruption risk in a multi-echelon supply chain

Abstract We demonstrate how system resilience can be improved by focusing on a supply chain network as a whole. We analyze inventory placement and back-up methodologies in a multi-echelon network and view their effect on reducing supply chain risk. We focus on risk from both supply disruptions and demand uncertainty and compare their impacts and mitigating strategies. A simulation model developed to capture an actual network for a consumer packaged goods company is used for the analysis. We present analysis and insights for multi-echelon networks and show how network utilization and proactive planning enable reductions in supply chain disruption impact.