cssi/SciSciGPT-SciSciNet huggingface dataset:
Profit Leak? Pre-Release File Sharing and the Music Industry

Using data from an exclusive file-sharing Web site that allows users to share music files using the BitTorrent protocol, I exploit exogenous variation in the availability of sound recordings in file-sharing networks to isolate the causal effect of file sharing of an album on its sales. Using within-album variation in illegal downloads and sales, I find that the effect is essentially zero: The elasticity of sales with respect to illegal downloads is one-tenth of one percentage point. However, the finding that file sharing is not harmful to individual artists is not inconsistent with the well-documented fact that file sharing is harmful to the music industry (the fallacy of composition). More important, I find that file sharing benefits more established and popular artists who are signed to major labels, which is consistent with recent industry trends.
Taking stock or cashing in? Shareholder style preferences, premiums and the method of payment

Abstract We develop and test hypotheses on the impact of target shareholders' investment style preferences on the method of payment and premiums in acquisitions. Stock offers (unlike cash offers) allow target shareholders to defer capital gains taxes. This deferral value, however, depends on target shareholders' willingness to retain acquirer stock. The empirical findings support our hypotheses. Bid premiums in stock offers are negatively and jointly related to target shareholder tax liabilities and to variables proxying for target shareholder willingness to hold acquirer stock. Moreover, the difference between predicted cash and stock premiums due to these factors significantly explains the method of payment choice.
Entry Threats and Pricing in the Generic Drug Industry

We use the unique regulatory environment of the pharmaceutical industry to examine how potential competition affects generic drug pricing. Our identification strategy exploits a provision of the Hatch-Waxman Act that awards 180 days of marketing exclusivity to the first valid generic drug applicant against the holder of a branded drug patent. In smaller drug markets, we find that price falls in response to an increase in potential competition. We also find that few manufacturers enter these markets, indicating this price reduction is an effective deterrent. In contrast, we find that generic incumbents accommodate entry in larger drug markets.
The Article III Problem in Bankruptcy

This Article reconsiders the implementation of Article III in the bankruptcy context. Recent rulings limiting the delegation of adjudicative power to non-Article III tribunals have generated only uncertainty and a profusion of litigation. The reason for this is that the Court’s Article III cases in this domain lack any foundational account of why bankruptcy judges implicate a constitutional problem. This Article identifies more precisely the Article III stakes in bankruptcy. Drawing on the well-tested creditors’ bargain theory of bankruptcy, it then develops a tractable, economically sophisticated constraint on congressional delegations. This account of bankruptcy’s necessary domain minimizes Article III and federalism harms while also enabling bankruptcy’s core operations to continue unhindered. To illustrate its utility, the Article applies that test to a range of common bankruptcy disputes, demonstrating that most (if not all) of the Court’s existing jurisprudence is sound in result, if not in reasoning. * University of Chicago Law School. Thanks to Douglas Baird and Ed Morrison for helpful conversations.
Toward a more communitarian future? Fukuyama as the fundamentalist secular humanist

With The End of History and the Last Man,' Francis Fukuyama2 established himself as the prophet of liberal democracy and free markets, heralding their triumph as the only form of governance capable of commanding legitimacy. Asked to reflect on his predictions a decade later, Fukuyama concluded that the greatest threat to liberalism comes from biotechnology because it alone has the potential to remake the human nature that liberal democracy was designed to serve. Fukuyama makes a compelling case that biotechnology may produce developments that should concern us; he is ironically less persuasive in articulating a liberal-democratic framework for governing the developments he fears. Our Posthuman Future: Consequences of the Biotechnology Revolution is provocative. It establishes the breadth of the threat Fukuyama perceives by linking four areas of biotechnology rarely discussed together: neuroscience and the ability to determine the genetic basis of traits like homosexuality or intelligence, pharmacology and the transformation of human psyches made possible by drugs such as Ritalin or Prozac,3 the potential to unlock the secrets of aging that could usher in revolutionary changes in demographics, and genetic
Congressional Will and the Role of the Executive in Bivens Actions: What Is Special about Special Factors?

Bivens v. Six Unknown Named Agents recognized a damages remedy when federal agents violate an individual’s constitutional rights. The Bivens case law denies that remedy when “special factors” mark a case, but never defines what constitutes a special factor. Through a detailed review of doctrine at both the Supreme Court and the federal Circuit court level, this article shows that the special factors analysis has evolved to maintain the proper balance of power between the judiciary and the legislature. Courts deciding whether to grant a constitutional damages remedy must probe the will of Congress to determine whether existing laws preclude a Bivens remedy. Providing a principled, coherent approach to the tangled history of special factors, my analysis demonstrates that courts err when they find special factors in the preferences or prerogatives of the executive.
Hiding homelessness: ‘quality of life’ laws and the politics of development in American cities

An incredibly disturbing trend has surfaced recently in local American politics: cities are forbidding citizens from feeding homeless people. My focus is on how this has been created in tandem with shifts in public discourse. Although I recognise the similarities between the new ordinances and previous anti-homeless laws, I want to point to something new that is happening in the legal treatment of street people. City governments, somewhat dependent on the non-profit sector to give material aid while government services are cut, are now vigorously targeting charities/citizens. I will argue that this trend relates to a shift in the framing of the homeless issue – more specifically, a shift in the very definition of the homeless.
Joint ventures around the globe from 1990–2000: Forms, types, industries, countries and ownership patterns

Abstract Joint ventures (JVs) and alliances are important forms of inter-organizational cooperation because they allow firms to achieve complex mutual tasks, otherwise impossible using simple arm's-length contracts, but without actually acquiring one another. In light of recent trends in globalization, this feature of JVs and alliances is vital to multi-national corporations (MNCs). These firms have complex operations, making simple arm's-length contracts insufficient. MNCs are also very large, so that mergers and acquisitions and takeovers are extremely expensive. In this paper, we describe global trends in JVs and alliances for the period 1990 to 2000, utilizing the Thomson Financial SDC Platinum database. We survey the relevant literature on JVs and alliances, and provide a detailed description of the world of JVs and alliances as depicted by this database. We report a number of interesting facts regarding the forms and types of JVs and alliances, their industry and geographic distribution, and patterns of ownership.
Free partition functions and an averaged holographic duality

We study the torus partition functions of free bosonic CFTs in two dimensions. Integrating over Narain moduli defines an ensemble-averaged free CFT. We calculate the averaged partition function and show that it can be reinterpreted as a sum over topologies in three dimensions. This result leads us to conjecture that an averaged free CFT in two dimensions is holographically dual to an exotic theory of three-dimensional gravity with U(1)c ×U(1)c symmetry and a composite boundary graviton. Additionally, for small central charge c, we obtain general constraints on the spectral gap of free CFTs using the spinning modular bootstrap, construct examples of Narain compactifications with a large gap, and find an analytic bootstrap functional corresponding to a single self-dual boson.
Bank Deposit Rate Clustering: Theory and Empirical Evidence

The market prices of stocks and other assets tend to cluster on round fractions. A similar clustering is found in the interest rates paid on retail bank deposits. However, the theoretical rationales given for asset-price clustering are incompatible with the clustering of retail deposit rates. This paper proposes a theory based on depositors? limited recall. It shows that when banks exploit this phenomenon, deposit rates will tend to be set at round fractions and will be relatively "sticky" at these levels. The implications of this theoretical model are tested using money market deposit account and retail certificate of deposit interest-rate data from a sample of more than 500 banks.
Pioneers versus Improvers: Enabling Optimal Patent Claim Scope

The enablement requirement is central to striking the balance between encouraging first-generation inventors and improvers. Unfortunately, the enablement doctrine is in disarray. Scholars have lambasted recent Federal Circuit decisions that apply seemingly inconsistent "full scope" and "single embodiment" tests for determining enablement. These complaints, however, are just one piece of a larger problem: the enablement doctrine incorporates an assortment of moving parts, and scholars, as well as the Federal Circuit, have not fully considered how these parts interact as a whole. This paper introduces a cohesive treatment of the enablement doctrine, and in doing so, seeks to calibrate the doctrine so that it more properly strikes the balance between pioneers and improvers. To this end, Part I introduces the tests that have troubled scholars and highlights these tests’ apparent inconsistencies. Part II proffers a theory that reconciles the tensions in the fragmented case law. Though critics cast the full scope rule as a “new enablement standard” that “vitiates old doctrines,” it is actually entirely consistent with preexisting doctrine. Contrary to critics’ claims, the single embodiment rule merely dictates that the patentee need not disclose alternate means for making or using the claimed invention. Accordingly, the single embodiment rule works alongside the full scope rule, and together, the rules are consistent with longstanding principles of enablement and literal infringement. Part III introduces and defends three reforms motivated by an understanding of the costs associated with the standard proposed in Part II. First, the Federal Circuit should reconsider its approach to undue experimentation.” Second, the Federal Circuit should resurrect the moribund maxim that claims should be construed narrowly when such construction is necessary to preserve their validity. The third reform addresses the relationship between enablement and later-developed technology. A critical but unresolved issue is how to treat embodiments that become possible only as a result of technology which arises after the patent application is filed. This final reform disentangles the inconsistent case law and proposes policy levers for isolating after-arising technologies which merit protection from those that do not.
Foreword: "Institutional corruption" defined.

This article defines the concept of institutional corruption and provides an analysis of its elements.
Locating decision rights: Evidence from the mutual fund industry

Abstract Mutual fund advisors make portfolio decisions for their funds on a daily basis. We examine the location of these portfolio decision rights on two dimensions. First, we consider the geographic location of the decision rights. Second, we consider whether the decision rights remain with an advisor or are allocated to an independent sub-advisor. We argue that the allocation of portfolio decision rights involves a tradeoff between the opportunity cost of not matching decision rights with specific knowledge, and the agency costs associated with moving the decision rights to the specific knowledge. The patterns in the location of decision rights are consistent with the tradeoff being a meaningful determinant of the allocation of decision rights in the mutual fund industry. We also find that funds that are predicted to be sub-advised and are sub-advised outperform those that are predicted to be sub-advised but are not.
Competition in Persuasion

We study symmetric information games where a number of senders choose what information to communicate. We show that the impact of competition on information revelation is ambiguous in general. We identify a condition on the information environment (i.e. the set of signals available to each sender) that is necessary and sufficient for equilibrium outcomes to be no less informative than the collusive outcome, regardless of preferences. The same condition also provides an easy way to characterize the equilibrium set and governs whether introducing additional senders or decreasing the alignment of senders' preferences necessarily increases the amount of information revealed.
Intergovernmental transfers and local education provision — Evaluating China's 8-7 National Plan for Poverty Reduction

Abstract Intergovernmental transfers are an important source of local public goods and services provision in many developing countries. Yet the empirical evidence on their effectiveness remains inconclusive partly because transfers are endogenous to political influence. This paper investigates the impact of a mix of intergovernmental transfers from a large-scale poverty relief program on local education spending in China between 1994 and 2000. Using a fuzzy regression discontinuity design, I first show no systematic evidence that counties benefiting from the program enhanced local education spending during the period of program implementation. I further show that the program has neither short-term nor long-term impacts on illiteracy reduction for the targeted counties.
A Supreme Stretch: The Supremacy Clause in the Wake of IRCA and Hoffman Plastic Compounds

Excerpt] Recently, the issues of immigration and immigration policy have garnered intense debate in the United States. Much of what Americans have discussed relates to border security, sanctions against employers who knowingly hire undocumented workers, and temporary and permanent paths to legalization for undocumented workers. This debate often overshadows a meaningful discussion about the future of workplace rights for undocumented workers who, despite their undocumented status, currently work in the United States and at times suffer labor and employment law violations in their workplaces. Unfortunately, the national immigration debate has not incorporated this discussion. Moreover, the current proposed federal immigration bills neither address nor clarify what effect they will have on the workplace rights of undocumented workers. Similar to Professor Cunningham-Parmeter’s article, this article focuses on one aspect of the new legal landscape for undocumented workers in the United States since the U.S. Supreme Court’s 2002 decision in Hoffman Plastic Compounds, Inc. v. NLRB. One central element of this new legal landscape is ongoing confusion about what effect, if any, immigration policy has on federal and state labor and employment law in the United States. Below, I take a first step toward clarifying the extent to which immigration policy affects the rights of states to extend the full protection of their state labor and employment laws to undocumented workers. Specifically, I address the following unresolved question currently before many lower courts: When, if ever, does federal immigration law preempt certain state labor and employment law remedies? First, I briefly describe why this question has emerged and has become important in U.S. courts. Next, I describe recent U.S. Supreme Court Supremacy Clause jurisprudence indicating that some lower courts’ answers to the preemption question described above threaten to stretch the Supremacy Clause beyond its constitutionallyintended boundaries.
Network Neutrality and the False Promise of Zero-Price Regulation

This Article examines zero-price regulation, the major distinguishing feature of many modern network neutrality proposals. A zero-price rule prohibits a broadband Internet access provider from charging an application or content provider (collectively, content provider) to send information to consumers. The Article differentiates two access provider strategies thought to justify a zero-price rule. Exclusion is anticompetitive behavior that harms a content provider to favor its rival. Extraction is a toll imposed upon content providers to raise revenue. Neither strategy raises policy concerns that justify implementation of a broad zero-price rule. First, there is no economic exclusion argument that justifies the zero-price rule as a general matter, given existing legal protections against exclusion. A stronger but narrow argument for regulation exists in certain cases in which the output of social producers, such as Wikipedia, competes with ordinary market-produced content. Second, prohibiting direct extraction is undesirable and counterproductive, in part because it induces costly and unregulated indirect extraction. I conclude, therefore, that recent calls for broad-based zero-price regulation are mistaken.
Alkane isomerization over sulfated zirconia and other solid acids

Some solid acids, including sulfated zirconia and certain industrial isomerization catalysts, catalyze two types of n-butane isomerizations, avoiding primary carbenium ions or carbonium ions: (1) an internal rearrangement of the C atoms in n-butane and (2) skeletal isomerization of n-butane to iso-butane. No superacid sites are required for these reactions. The skeletal isomerization is an intermolecular reaction, involving a C8 intermediate. Easily accessible Bronsted acid sites and small amounts of olefin are crucial. Spectroscopic examination of the acid sites on sulfated zirconia shows that they are not stronger than the acid sites in zeolites such as HY. The butane isomerization rate is suppressed by CO, even when no CO is adsorbed on Lewis sites; formation of oxocarbenium ions is likely. The decisive role of Bronsted acid sites is demonstrated by results on deuterated catalysts.
Marginal modeling of cluster-period means and intraclass correlations in stepped wedge designs with binary outcomes

Stepped wedge cluster randomized trials (SW-CRTs) with binary outcomes are increasingly used in prevention and implementation studies. Marginal models represent a flexible tool for analyzing SW-CRTs with population-averaged interpretations, but the joint estimation of the mean and intraclass correlation coefficients (ICCs) can be computationally intensive due to large cluster-period sizes. Motivated by the need for marginal inference in SW-CRTs, we propose a simple and efficient estimating equations approach to analyze cluster-period means. We show that the quasi-score for the marginal mean defined from individual-level observations can be reformulated as the quasi-score for the same marginal mean defined from the cluster-period means. An additional mapping of the individual-level ICCs into correlations for the cluster-period means further provides a rigorous justification for the cluster-period approach. The proposed approach addresses a long-recognized computational burden associated with estimating equations defined based on individual-level observations, and enables fast point and interval estimation of the intervention effect and correlations. We further propose matrix-adjusted estimating equations to improve the finite-sample inference for ICCs. By providing a valid approach to estimate ICCs within the class of generalized linear models for correlated binary outcomes, this article operationalizes key recommendations from the CONSORT extension to SW-CRTs, including the reporting of ICCs.
The incidence of extreme economic stress: Evidence from utility disconnections

This paper uses monthly zip code-level data on electricity disconnections to document the socioeconomic correlates of extreme economic distress among 5 million customers in Illinois. In 2018-2019, customers in Black and Hispanic zip codes were about 4 times more likely to be disconnected for non-payment, 2-3 times more likely to be on deferred payment plans, and 70% more likely to participate in utility-based low-income assistance programs, controlling for zip code distributions of income and other demographic characteristics. During the COVID-19 pandemic, there has been a nine-fold expansion in low-income assistance to pay utility bills, but disconnections were double and deferred payment plans triple their historical averages in October 2020. Disconnection notices were served to 2.5% of commercial and industrial accounts, and 3.4% of residential accounts each month in late 2020. About 20% of all accounts were charged late fees. The odds for each of these measures were multiples higher in minority and low-income zip codes.
Exploiting Local and Cloud Sensor Fusion in Intermittently Connected Sensor Networks

We consider a detection problem where sensors experience noisy measurements and intermittent communication opportunities to a centralized fusion center (or cloud). The objective of the problem is to arrive at the correct estimate of event detection in the environment. The sensors may communicate locally with other sensors (local clusters) where they fuse their noisy sensor data to estimate the detection of an event locally. In addition, each sensor cluster can intermittently communicate to the cloud, where a centralized fusion center fuses estimates from all sensor clusters to make a final determination regarding the occurrence of the event across the deployment area. We refer to this hybrid communication scheme as a cloud-cluster architecture. Minimizing the expected loss function of networks where noisy sensors are intermittently connected to the cloud, as in our hybrid communication scheme, has not been investigated to our knowledge. We leverage recently improved concentration inequalities to arrive at an optimized decision rule for each cluster and we analyze the expected detection performance resulting from our hybrid scheme. Our analysis shows that clustering the sensors provides resilience to noise in the case of low communication probability with the cloud. For larger clusters, a steep improvement in detection performance is possible even for a low communication probability by using our cloud-cluster architecture.
Call to Duty: Just-in-Time Scheduling in a Restaurant Chain

Just-in-time scheduling has become ubiquitous in the service industries. Although effective in reducing staffing level, hence labor cost, the potential impact of just-in-time scheduling on workers’...
Transcriptional and Translational Responsiveness of the Neisseria gonorrhoeae Type IV Secretion System to Conditions of Host Infections.

The type IV secretion system of Neisseria gonorrhoeae translocates single-stranded DNA into the extracellular space, facilitating horizontal gene transfer and initiating biofilm formation. Expression of this system has been observed to be low under laboratory conditions, and multiple levels of regulation have been identified. We used a translational fusion of lacZ to traD, the gene for the type IV secretion system coupling protein, to screen for increased type IV secretion system expression. We identified several physiologically relevant conditions, including surface adherence, decreased manganese or iron, and increased zinc or copper, which increase gonococcal type IV secretion system protein levels through transcriptional and/or translational mechanisms. These metal treatments are reminiscent of the conditions in the macrophage phagosome. The ferric uptake regulator, Fur, was found to repress traD transcript levels, but to also have a second role, acting to allow TraD protein levels to increase only in the absence of iron. To better understand type IV secretion system regulation during infection, we examined transcriptomic data from active urethral infection samples from five men. These data demonstrated differential expression of 20 of 21 type IV secretion system genes during infection, indicating upregulation of genes necessary for DNA secretion during host infection.
Some continuous and discontinuous Galerkin methods and structure preservation for incompressible flows

In this paper, we present consistent and inconsistent discontinuous Galerkin methods for incompressible Euler and Navier-Stokes equations with the kinematic pressure, Bernoulli function and EMAC function. Semi- and fully discrete energy stability of the proposed dG methods are proved in a unified fashion. Conservation of total energy, linear and angular momentum is discussed with both central and upwind fluxes. Numerical experiments are presented to demonstrate our findings and compare our schemes with conventional schemes in the literature in both unsteady and steady problems. Numerical results show that global conservation of the physical quantities may not be enough to demonstrate the performance of the schemes, and our schemes are competitive and able to capture essential physical features in several benchmark problems.
Effects of Nose Bluntness on Hypersonic Boundary-Layer Receptivity and Stability

High-speed laminar-to-turbulent transition over blunt bodies is relevant to a variety of aerodynamic applications. Experiments have observed that beyond a critical value of the nose radius the init...
Pulmonary Manifestations of Immune Dysregulation in CTLA‐4 Haploinsufficiency and LRBA Deficiency

Objective The primary immunodeficiency syndromes of cytotoxic T lymphocyte-associated protein 4 (CTLA-4) haploinsufficiency and lipopolysaccharide-responsive and beige-like anchor protein (LRBA) deficiency present with multisystem immune dysregulation. The aim of this study was to characterize and compare the pulmonary manifestations of these two diseases. Methods We retrospectively analyzed the pulmonary clinical, radiologic, and histopathologic characteristics of 6 patients with CTLA-4 haploinsufficiency and 4 patients with LRBA deficiency with pulmonary involvement followed at a large tertiary care center. Results Chronic respiratory symptoms were more frequent in patients with LRBA deficiency versus CTLA-4 haploinsufficiency (3/4 versus 1/6). Cough was the most common respiratory symptom. Abnormalities in pulmonary exam and pulmonary function testing were more frequent in LRBA deficiency (4/4, 2/4) compared to CTLA-4 haploinsufficiency (1/6, 2/6). Chest CT findings included mediastinal lymphadenopathy (4/4 in LRBA deficiency versus 1/4 in CTLA-4 haploinsufficiency), pulmonary nodules (4/4, 3/4), ground-glass opacification (4/4, 3/4), and bronchiectasis (3/4, 1/4). Lymphocytic inflammation, concentrated bronchovasculocentrically and paraseptally, was the predominant pathologic finding and was observed in all patients who had lung biopsies (N=3 with LRBA deficiency; N=3 with CTLA-4 haploinsufficiency). Conclusion Despite phenotypic overlap amongst these diseases, LRBA deficiency demonstrated greater severity of pulmonary disease, indicated by respiratory symptoms, pulmonary exam, and intrathoracic radiologic findings. Chest CT was the most sensitive indicator of pulmonary involvement in both disorders. Lymphocytic inflammation is the key histologic feature of both disorders. Pediatric pulmonologists should consider these disorders of immune dysregulation in the relevant clinical context to provide earlier diagnosis, comprehensive pulmonary evaluation and treatment. This article is protected by copyright. All rights reserved.
Experimental Analysis of Locality Sensitive Hashing Techniques for High-Dimensional Approximate Nearest Neighbor Searches.

Finding nearest neighbors in high-dimensional spaces is a fundamental operation in many multimedia retrieval applications. Exact tree-based approaches are known to suffer from the notorious curse of dimensionality for high-dimensional data. Approximate searching techniques sacrifice some accuracy while returning good enough results for faster performance. Locality Sensitive Hashing (LSH) is a popular technique for finding approximate nearest neighbors. There are two main benefits of LSH techniques: they provide theoretical guarantees on the query results, and they are highly scalable. The most dominant costs for existing external memory-based LSH techniques are algorithm time and index I/Os required to find candidate points. Existing works do not compare both of these costs in their evaluation. In this experimental survey paper, we show the impact of both these costs on the overall performance. We compare three state-of-the-art techniques on six real-world datasets, and show the importance of comparing these costs to achieve a more fair comparison.
Exploiting symmetry in the power flow equations using monodromy

We propose solving the power flow equations using monodromy. We prove the variety under consideration decomposes into trivial and nontrivial subvarieties and that the nontrivial subvariety is irreducible. We also show various symmetries in the solutions. We finish by giving numerical results comparing monodromy against polyhedral and total degree homotopy methods and giving an example of a network where we can find all solutions to the power flow equation using monodromy where other homotopy techniques fail. This work gives hope that finding all solutions to the power flow equations for networks of realistic size is possible.
Oracle posterior contraction rates under hierarchical priors

We offer a general Bayes theoretic framework to derive posterior contraction rates under a hierarchical prior design: the first-step prior serves to assess the model selection uncertainty, and the second-step prior quantifies the prior belief on the strength of the signals within the model chosen from the first step. In particular, we establish non-asymptotic oracle posterior contraction rates under (i) a local Gaussianity condition on the log likelihood ratio of the statistical experiment, (ii) a local entropy condition on the dimensionality of the models, and (iii) a sufficient mass condition on the second-step prior near the best approximating signal for each model. The first-step prior can be designed generically. The posterior distribution enjoys Gaussian tail behavior and therefore the resulting posterior mean also satisfies an oracle inequality, automatically serving as an adaptive point estimator in a frequentist sense. Model mis-specification is allowed in these oracle rates. The local Gaussianity condition serves as a unified attempt of non-asymptotic Gaussian quantification of the experiments, and can be easily verified in various experiments considered in [GvdV07a] and beyond. The general results are applied in various problems including: (i) trace regression, (ii) shape-restricted isotonic/convex regression, (iii) high-dimensional partially linear regression, (iv) covariance matrix estimation in the sparse factor model, (v) detection of non-smooth polytopal image boundary, and (vi) intensity estimation in a Poisson point process model. These new results serve either as theoretical justification of practical prior proposals in the literature, or as an illustration of the generic construction scheme of a (nearly) minimax adaptive estimator for a complicated experiment.
Efficiently solving quantified bit-vector formulas

In recent years, bit-precise reasoning has gained importance in hardware and software verification. Of renewed interest is the use of symbolic reasoning for synthesising loop invariants, ranking functions, or whole program fragments and hardware circuits. Solvers for the quantifier-free fragment of bit-vector logic exist and often rely on SAT solvers for efficiency. However, many techniques require quantifiers in bit-vector formulas to avoid an exponential blow-up during construction. Solvers for quantified formulas usually flatten the input to obtain a quantified Boolean formula, losing much of the word-level information in the formula. We present a new approach based on a set of effective word-level simplifications that are traditionally employed in automated theorem proving, heuristic quantifier instantiation methods used in SMT solvers, and model finding techniques based on skeletons/templates. Experimental results on two different types of benchmarks indicate that our method outperforms the traditional flattening approach by multiple orders of magnitude of runtime.
Journey to the center of stars: The realm of low Prandtl number fluid dynamics

Turbulence deep within the interior of stars bears many qualitative similarities with turbulence in the ocean and atmosphere on Earth. In both contexts, various forms of convective instabilities and shear instabilities govern the transport of heat, momentum (angular momentum) and chemical species. However, an important distinction between stellar fluids and geophysical fluids is the value of the Prandtl number, which is of order unity in oceanic and atmospheric flows, and asymptotically small in stars. As a result, many well-known scaling laws for turbulent transport in geophysical flows must be revisited at low Prandtl number, as reviewed in this paper.
Are patients really getting what they want? The routine implementation of decision aids for patients with hip or knee osteoarthritis in the high value healthcare collaborative and alignment between patient treatment choice and receipt

RATIONALE, AIMS AND OBJECTIVES Alignment between patients' treatment choices and treatments received is acknowledged as an important outcome of shared decision-making (SDM), yet recent research suggests that patients' choices do not always align with their actual treatment trajectories. This paper explores the alignment of patient-expressed treatment choices (for surgery or medical management) after exposure to decision aids and treatments received among patients with hip or knee osteoarthritis within High Value Healthcare Collaborative (HVHC) systems as the collaborative integrated decision aids intended to support SDM into routine clinical practice. METHOD This retrospective cohort study examines data from adult (≥18 years) patients with hip or knee osteoarthritis who received decision aids as part of orthopaedic consultations within HVHC systems between 2012 and 2015. Multivariable logistic regression explored the association between patient-level characteristics with the odds of treatment choice-receipt alignment. RESULTS The majority of patients with knee osteoarthritis (68.3%) and hip osteoarthritis (71.9%) received treatments aligned with their choices following exposure to decision aids, but analyses reveal important differences in the odds of such alignment across patient characteristics. In adjusted models, African American patients with knee osteoarthritis had 50% lower odds of receiving treatment aligned with their choices compared with Caucasian patients (OR = 0.52, P < .05). Medicare- or Medicaid-insured knee patients had 49% and 59% lower odds (respectively) of receiving choice-aligned treatments relative to privately insured patients. Patients with knee (OR = 0.40, P < .01) or hip (OR = 0.75, P < .05) osteoarthritis at earlier decision-making stages had lower odds of receiving treatments congruent with their choices. CONCLUSION This work elucidates the odds of treatment choice-aligned care for patients within health care systems attempting to routinely integrate decision aids to support SDM into clinical practice and underscores the gaps in achieving this alignment among African American patients, those with public insurance and those at early decision-making stages.
Mitochondria-dependent phase separation of disease-relevant proteins drives pathological features of age-related macular degeneration

Age-related macular degeneration (AMD) damages the retinal pigment epithelium (RPE), the tissue that safeguards photoreceptor health, leading to irreversible vision loss. Polymorphisms in cholesterol and complement genes are implicated in AMD, yet mechanisms linking risk variants to RPE injury remain unclear. We sought to determine how allelic variants in the apolipoprotein E cholesterol transporter modulate RPE homeostasis and function. Using live-cell imaging, we show that inefficient cholesterol transport by the AMD risk-associated ApoE2 increases RPE ceramide, leading to autophagic defects and complement-mediated mitochondrial damage. Mitochondrial injury drives redox state-sensitive cysteine-mediated phase separation of ApoE2, forming biomolecular condensates that could nucleate drusen. The protective ApoE4 isoform lacks these cysteines and is resistant to phase separation and condensate formation. In Abca4-/- Stargardt macular degeneration mice, mitochondrial dysfunction induces liquid-liquid phase separation of p62/SQSTM1, a multifunctional protein that regulates autophagy. Drugs that decrease RPE cholesterol or ceramide prevent mitochondrial injury and phase separation in vitro and in vivo. In AMD donor RPE, mitochondrial fragmentation correlates with ApoE and p62 condensates. Our studies demonstrate that major AMD genetic and biological risk pathways converge upon RPE mitochondria, and identify mitochondrial stress-mediated protein phase separation as an important pathogenic mechanism and promising therapeutic target in AMD.
Theory of plasma contactors in ground-based experiments and low earth orbit

An examination of several models of electron collection by plasma contactors leads to a definition of the range of validity and applicability for each model. It is noted that most present ground-based experiments are of limited relevance to space applications of plasma contactors, since they operate in a regime where the magnetic field and effective collisions are at most only marginally important. An exception is the experiment of Stenzel and Urrutia (1986), which examined a plasma whose electron Larmor radius was small by comparison to the scale of the potential, and in which the anomalous transport of electrons across the magnetic field was important. The enhanced electron current was not continuous in time, but occurred in periodic bursts as the instabilities periodically emerged, saturated, and decayed.
Intersection-Traffic Control of Autonomous Vehicles using Newton-Raphson Flows and Barrier Functions

Abstract This paper concerns an application of a recently-developed nonlinear tracking technique to trajectory control of autonomous vehicles at traffic intersections. The technique uses a flow version of the Newton-Raphson method for controlling a predicted system-output to a future reference target. Its implementations are based on numerical solutions of ordinary differential equations, and it does not specify any particular method for computing its future reference trajectories. Consequently it can use relatively simple algorithms on crude models for computing the target trajectories, and more-accurate models and algorithms for trajectory control in the tight loop. We demonstrate this point on an extant predictive traffic planning-and-control method with our tracking technique. Furthermore, we guarantee safety specifications by applying to the tracking technique the framework of control barrier functions.
Variants of the aortic arch in adult general population and their association with thoracic aortic aneurysm disease

Background Query a single institution computed tomography (CT) database to assess the prevalence of aortic arch anomalies in general adult population and their potential association with thoracic aortopathies. Methods CT chest scan reports of patients aged 50-85 years old performed for any indication at a single health system between 2013 and 2016 were included in the analysis. Characteristics of patients with and without aortic arch anomalies were compared by t test and Fisher exact tests. Logistic regression analysis was performed to assess for independent risk factors of thoracic aortic aneurysm (TAA). Results Of 21,336 CT scans, 603 (2.8%) described arch anomalies. Bovine arch (n = 354, 58.7%) was the most common diagnosis. Patients with arch anomalies were more likely to be female (p Conclusions Reported prevalence of aortic arch anomalies by CT imaging in the older adult population is approximately 3%, with high association of TAA (OR = 2.85) incidence in this subgroup. This may warrant a more tailored surveillance strategy for aneurysm disease in this subpopulation.
Automatically enforcing fresh and consistent inputs in intermittent systems

Intermittently powered energy-harvesting devices enable new applications in inaccessible environments. Program executions must be robust to unpredictable power failures, introducing new challenges in programmability and correctness. One hard problem is that input operations have implicit constraints, embedded in the behavior of continuously powered executions, on when input values can be collected and used. This paper aims to develop a formal framework for enforcing these constraints. We identify two key properties---freshness (i.e., uses of inputs must satisfy the same time constraints as in continuous executions) and temporal consistency (i.e., the collection of a set of inputs must satisfy the same time constraints as in continuous executions). We formalize these properties and show that they can be enforced using atomic regions. We develop Ocelot, an LLVM-based analysis and transformation tool targeting Rust, to enforce these properties automatically. Ocelot provides the programmer with annotations to express these constraints and infers atomic region placement in a program to satisfy them. We then formalize Ocelot's design and show that Ocelot generates correct programs with little performance cost or code changes.
Tabular Transformers for Modeling Multivariate Time Series

Tabular datasets are ubiquitous in data science applications. Given their importance, it seems natural to apply state-of-the-art deep learning algorithms in order to fully unlock their potential. Here we propose neural network models that represent tabular time series that can optionally leverage their hierarchical structure. This results in two architectures for tabular time series: one for learning representations that is analogous to BERT and can be pre-trained end-to-end and used in downstream tasks, and one that is akin to GPT and can be used for generation of realistic synthetic tabular sequences. We demonstrate our models on two datasets: a synthetic credit card transaction dataset, where the learned representations are used for fraud detection and synthetic data generation, and on a real pollution dataset, where the learned encodings are used to predict atmospheric pollutant concentrations. Code and data are available at https://github.com/IBM/TabFormer.
Peptide-based supramolecular vaccine systems ☆

Currently approved replication-competent and inactivated vaccines are limited by excessive reactogenicity and poor safety profiles, while subunit vaccines are often insufficiently immunogenic without co-administering exogenous adjuvants. Self-assembling peptide-, peptidomimetic-, and protein-based biomaterials offer a means to overcome these challenges through their inherent modularity, multivalency, and biocompatibility. As these scaffolds are biologically derived and present antigenic arrays reminiscent of natural viruses, they are prone to immune recognition and are uniquely capable of functioning as self-adjuvanting vaccine delivery vehicles that improve humoral and cellular responses. Beyond this intrinsic immunological advantage, the wide range of available amino acids allows for facile de novo design or straightforward modifications to existing sequences. This has permitted the development of vaccines and immunotherapies tailored to specific disease models, as well as generalizable platforms that have been successfully applied to prevent or treat numerous infectious and non-infectious diseases. In this review, we briefly introduce the immune system, discuss the structural determinants of coiled coils, β-sheets, peptide amphiphiles, and protein subunit nanoparticles, and highlight the utility of these materials using notable examples of their innate and adaptive immunomodulatory capacity. STATEMENT OF SIGNIFICANCE: Subunit vaccines have recently gained considerable attention due to their favorable safety profiles relative to traditional whole-cell vaccines; however, their reduced efficacy requires co-administration of reactogenic adjuvants to boost immune responses. This has led to collaborative efforts between engineers and immunologists to develop nanomaterial-based vaccination platforms that can elicit protection without deleterious side effects. Self-assembling peptidic biomaterials are a particularly attractive approach to this problem, as their structure and function can be controlled through primary sequence design and their capacity for multivalent presentation of antigens grants them intrinsic self-adjuvanticity. This review introduces the various architectures adopted by self-assembling peptides and discusses their application as modulators of innate and adaptive immunity.
Physical limitations on broadband invisibility based on fast-light media

This note is a comment on a recent article [Tsakmakidis, et al., Nat Commun 10 (2019)] that presents a thought-provoking proposal to overcome the bandwidth restrictions of invisibility cloaks based on using media that support superluminal (faster than light in free space) group and phase velocities. As illustrated in Fig. 1 of the original article, a wave packet propagating through such a fast-light cloak is alleged to be able to reach the side behind the cloaked object simultaneously with a corresponding wave packet propagating through the shorter, direct route in free space without the object, so that "no shadow or waveform distortion arises." As the authors claim, the "extra pathlength is balanced out by the correspondingly larger group velocity of the pulse in the cloak", which allows to "restore the incident field distribution all around the object in, both, amplitude and phase". This fast-light effect may be achieved in a broadband fashion using active (gain) materials. The authors claim that such a fast-light cloak can hide an object, even from time-of-flight detection techniques, and achieve invisibility "over any desired frequency band." We disagree with these claims and believe that a thorough clarification of the ideas put forward in the original article is important and necessary for the broad wave-physics community. Specifically, in this comment we clarify that invisibility cloaks based on fast-light media suffer from fundamental bandwidth restrictions that arise due to causality, the nature of superluminal wave propagation, and the stability issues of active systems. These limitations and issues were not addressed in [Tsakmakidis, et al., Nat Commun 10 (2019)]. Most importantly, we show that the material model considered in the original article is unphysical.