cssi/SciSciGPT-SciSciNet huggingface dataset:
A Formula for the Partition Function That “Counts”

We derive a combinatorial multisum expression for the number D(n, k) of partitions of n with Durfee square of order k. An immediate corollary is therefore a combinatorial formula for p(n), the number of partitions of n. We then study D(n, k) as a quasipolynomial. We consider the natural polynomial approximation $${\tilde{D}(n, k)}$$ to the quasipolynomial representation of D(n, k). Numerically, the sum $${\sum_{1\leq k \leq \sqrt{n}} \tilde{D}(n, k)}$$ appears to be extremely close to the initial term of the Hardy-Ramanujan-Rademacher convergent series for p(n).
The global health network on alcohol control: successes and limits of evidence-based advocacy

Global efforts to address alcohol harm have significantly increased since the mid-1990 s. By 2010, the World Health Organization (WHO) had adopted the non-binding Global Strategy to Reduce the Harmful Use of Alcohol. This study investigates the role of a global health network, anchored by the Global Alcohol Policy Alliance (GAPA), which has used scientific evidence on harm and effective interventions to advocate for greater global public health efforts to reduce alcohol harm. The study uses process-tracing methodology and expert interviews to evaluate the accomplishments and limitations of this network. The study documents how network members have not only contributed to greater global awareness about alcohol harm, but also advanced a public health approach to addressing this issue at the global level. Although the current network represents an expanding global coalition of like-minded individuals, it faces considerable challenges in advancing its cause towards successful implementation of effective alcohol control policies across many low- and middle-income countries (LMICs). The analysis reveals a need to transform the network into a formal coalition of regional and national organizations that represent a broader variety of constituents, including the medical community, consumer groups and development-focused non-governmental organizations. Considering the growing harm of alcohol abuse in LMICs and the availability of proven and cost-effective public health interventions, alcohol control represents an excellent 'buy' for donors interested in addressing non-communicable diseases. Alcohol control has broad beneficial effects for human development, including promoting road safety and reducing domestic violence and health care costs across a wide variety of illnesses caused by alcohol consumption.
Gapped boundary phases of topological insulators via weak coupling

The standard boundary state of a topological insulator in 3 + 1 dimensions has gapless charged fermions. We present model systems that reproduce this standard gapless boundary state in one phase, but also have gapped phases with topological order. Our models are weakly coupled and all the dynamics is explicit. We rederive some known boundary states of topological insulators and construct new ones. Consistency with the standard spin/charge relation of condensed matter physics places a nontrivial constraint on models.
Metal–Organic Frameworks Stabilize Solution-Inaccessible Cobalt Catalysts for Highly Efficient Broad-Scope Organic Transformations

New and active earth-abundant metal catalysts are critically needed to replace precious metal-based catalysts for sustainable production of commodity and fine chemicals. We report here the design of highly robust, active, and reusable cobalt-bipyridine- and cobalt-phenanthroline-based metal–organic framework (MOF) catalysts for alkene hydrogenation and hydroboration, aldehyde/ketone hydroboration, and arene C–H borylation. In alkene hydrogenation, the MOF catalysts tolerated a variety of functional groups and displayed unprecedentedly high turnover numbers of ∼2.5 × 106 and turnover frequencies of ∼1.1 × 105 h–1. Structural, computational, and spectroscopic studies show that site isolation of the highly reactive (bpy)Co(THF)2 species in the MOFs prevents intermolecular deactivation and stabilizes solution-inaccessible catalysts for broad-scope organic transformations. Computational, spectroscopic, and kinetic evidence further support a hitherto unknown (bpy•–)CoI(THF)2 ground state that coordinates to alk...
New fermion discretizations and their applications

We review the recent progress in new lattice fermion setups. We focus on the following three types which have possibility of improving lattice simulations. (1) Flavored-mass fermions are a generalization of Wilson fermions with species-splitting mass terms. In particular, staggeredWilson fermions initiated by Adams have possibilities of reducing numerical costs in overlap fermions and the influence of taste-breaking in staggered fermions. (2) Central-branch Wilson fermions, in which additive mass renormalization is forbidden by extra axial symmetry, could enable us to perform Wilson-fermion lattice QCD without fine-tuning. (3) Minimally doubled fermions, which reduce the number of species by species-dependent chemical potential terms, realizes a ultra-local chiral fermion at the price of hypercubic symmetry. These setups reveal unknown aspects of lattice fermions, and we obtain a deeper understanding of lattice field theory.
Pinching the Poor? Medicaid Cost Sharing Under the ACA

Some U.S. states have begun experimenting with increased cost sharing for Medicaid enrollees, but policymakers will need to monitor such programs carefully to understand their impact on costs, quality, access, and health.
Comparing neonatal morbidity and mortality estimates across specialty in periviable counseling

AbstractObjective: To describe and compare estimates of neonatal morbidity and mortality communicated by neonatologists and obstetricians in simulated periviable counseling encounters.Methods: A simulation-based study of 16 obstetricians (OBs) and 15 neonatologists counseling standardized patients portraying pregnant women with ruptured membranes at 23 weeks gestation. Two investigators tabulated all instances of numerically-described risk estimates across individuals and by specialty.Results: Overall, 12/15 (80%) neonatologists utilized numeric estimates of survival; 6/16 (38%) OBs did. OBs frequently deferred the discussion of “exact numbers” to neonatologists. The 12 neonatologists provided 13 unique numeric estimates, ranging from 3% to 50% survival. Half of those neonatologists provided two to three different estimates in a single encounter. By comparison, six OBs provided four unique survival estimates (“50%”, “30–40%”, “1/3–1/2”, “<10%”). Only 2/15 (13%) neonatologists provided numeric estimates of...
The profit-maximizing non-profit

Consider an organization that solicits private contributions, which will partly be used to provide a public good. The organization’s goals is to maximize its profits, namely the difference between aggregate contributions and the amount it spends on providing the public good. An equilibrium exists in which many persons contribute, each contributor enjoys zero consumer surplus from contributing, and the organization takes as a profit the contributions of all but one donor. Such behavior by the organization is consistent with incomplete crowding out of governmental grants. Furthermore, when the organization is constrained to spend at least fraction of all contributions on the public good, it can have an incentive to produce inefficiently. ∗I am grateful to participants at a seminar at KU Leuven, to the hospitality of the Max Planck Institute for Tax Law and Public Finance, and particularly to Kai Konrad, for stimulating conversations.
Axisymmetric plasma equilibrium in gravitational and magnetic fields

Plasma equilibria in gravitational and open-ended magnetic fields are considered for the case of topologically disconnected regions of the magnetic flux surfaces where plasma occupies just one of these regions. Special dependences of the plasma temperature and density on the magnetic flux are used which allow the solution of the Grad–Shafranov equation in a separable form permitting analytic treatment. It is found that plasma pressure tends to play the dominant role in the setting the shape of magnetic field equilibrium, while a strong gravitational force localizes the plasma density to a thin disc centered at the equatorial plane.
Organocatalytic Carbonyl-Olefin Metathesis

The development of a catalytic carbonyl-olefin metathesis strategy is reported, in the context of the ring-opening metathesis of cyclopropenes with aldehydes using a simple hydrazine catalyst. The key to this reaction is a conceptual blueprint for metathesis chemistry that forgoes the traditional reliance on [2 + 2] cycloaddition modes in favor of a [3 + 2] paradigm.
Mesoscopic Features of Charge Generation in Organic Semiconductors

ConspectusIn the past two decades, organic materials have been extensively investigated by numerous research groups worldwide for implementation in organic photovoltaic (OPV) devices. The interest in organic semiconductors is spurred by their potential low cost and facile tunability, making OPV devices a potentially disruptive technology. To study OPV operating mechanisms is also to explore a knowledge gap in our general understanding of materials, because both the time scales (femtosecond to microsecond) and length scales (nanometer to micrometer) relevant to OPV functionality occupy a challenging and fascinating space between the traditional regimes of quantum chemistry and solid-state physics.New theoretical frameworks and computational tools are needed to bridge the aforementioned length and time scales, and they must satisfy the criteria of computational tractability for systems involving 104–106 atoms, while also maintaining predictive utility. While this challenge is far from solved, advances in de...
Aluminum(III)-Catalyzed, Formal Homo-Nazarov-Type Ring-Opening Cyclizations toward the Synthesis of Functionalized Tetrahydroindolizines

A general approach to functionalized 5,6,7,8-tetrahydroindolizines (THIs) is disclosed. The THIs are directly formed from Al(OTf)3-catalyzed, formal homo-Nazarov-type ring-opening cyclizations of N-pyrrolyl cyclopropyl malonamides. The THI products were stable to silica gel chromatography and isolated in up to 97% yield with diastereomeric ratios up to 4.0:1. The cyclization demonstrates good substrate scope as aryl, heteroaryl, gem-dialkyl, heteroatomic, and silylmethyl donor groups on the cyclopropane are tolerated. Moreover, the protocol is both pharmaceutically relevant and environmentally friendly as a cheap, earth-abundant metal catalyst is used along with acetonitrile as a greener solvent.
Leveraging Visual Question Answering for Image-Caption Ranking

Visual Question Answering (VQA) is the task of taking as input an image and a free-form natural language question about the image, and producing an accurate answer. In this work we view VQA as a “feature extraction” module to extract image and caption representations. We employ these representations for the task of image-caption ranking. Each feature dimension captures (imagines) whether a fact (question-answer pair) could plausibly be true for the image and caption. This allows the model to interpret images and captions from a wide variety of perspectives. We propose score-level and representation-level fusion models to incorporate VQA knowledge in an existing state-of-the-art VQA-agnostic image-caption ranking model. We find that incorporating and reasoning about consistency between images and captions significantly improves performance. Concretely, our model improves state-of-the-art on caption retrieval by 7.1 % and on image retrieval by 4.4 % on the MSCOCO dataset.
Immunoglobulin Classification Using the Colored Antibody Graph

Abstract The somatic recombination of V, D, and J gene segments in B-cells introduces a great deal of diversity, and divergence from reference segments. Many recent studies of antibodies focus on the population of antibody transcripts that show which V, D, and J gene segments have been favored for a particular antigen, a repertoire. To properly describe the antibody repertoire, each antibody must be labeled by its constituting V, D, and J gene segment, a task made difficult by somatic recombination and hypermutation events. While previous approaches to repertoire analysis were based on sequential alignments, we describe a new de Bruijn graph–based algorithm to perform VDJ labeling and benchmark its performance.
Potential Complications in Myelography: I. Technical Considerations

Scanning electron microscopy demonstrated starch powder contamination on the stylet tip from a spinal needle after it was lightly touched with nonwashed surgical gloves. A sterile solution of Pantopaque was injected through the spinal needle after the stylet was withdrawn and carried particulate contaminants to a 0.2 μm millipore filter. Using both scanning electron microscopy and energy dispersive x-ray analysis, particles of various sizes (mostly 5–10 microns) and variable compositions, including starch, talc, and other elements, were identified. Also, glass particles from the Pantopaque vial and plastic particles from the plastic syringe and tubing used in drawing up the Pantopaque were seen. These observations indicate that strict attention to proper technique in myelography is essential in order to eliminate potential cerebrospinal fluid contamination.
"Will I always be not social?": Re-Conceptualizing Sociality in the Context of a Minecraft Community for Autism

Traditional face-to-face social interactions can be challenging for individuals with autism, leading some to perceive and categorize them as less social than their typically-developing peers. Individuals with autism may even see themselves as less social relative to their peers. Online communities can provide an alternative venue for social expression, enabling different types of communication beyond face-to-face, oral interaction. Using ethnographic methods, we studied the communication ecology that has emerged around a Minecraft server for children with autism and their allies. Our analysis shows how members of this community search for, practice, and define sociality through a variety of communication channels. These findings suggest an expansion in how sociality has traditionally been conceptualized for individuals with autism.
The Association between Nocturnal Cardiac Arrhythmias and Sleep-Disordered Breathing: The DREAM Study.

Study Objectives:To determine whether sleep-disordered breathing (SDB) is associated with cardiac arrhythmia in a clinic-based population with multiple cardiovascular comorbidities and severe SDB.M...
Effects of Diflunisal on Platelet Function and Fecal Blood Loss.

The effects of diflunisal, a nonacetylated difluorinated salicylate, on platelet function were compared with those of aspirin and placebo. In a randomized, double-blind trial, normal subjects were given diflunisal, 250, 500, or 1,000 mg twice daily; aspirin, 650 or 1,300 mg twice daily; or placebo for 8-day periods. Diflunisal, 250 mg, had no effect on platelet function, whereas 500 mg induced minimal inhibition of collagen-induced release of platelet serotonin, and 1,000 mg inhibited platelet malondialdehyde-production, moderately prolonged template bleeding times (p = NS), and increased fecal blood loss (p less than 0.05). In contrast, aspirin, 650 mg, markedly inhibited collagen-induced platelet aggregation and serotonin release, and 1,300 mg prolonged bleeding time (p less than 0.01) and increased focal blood loss (p less than 0.01). The effects of aspirin lasted for up to 5 days, whereas changes induced by diflunisal had returned to baseline 24 hours after the drug was discontinued. We conclude that in doses in the same range as those of aspirin diflunisal inhibits platelet function less.
How Accurate Is the Dating of Scheduled 39-Week Deliveries?

Objective We assessed the impact of a policy preventing scheduled repeat cesarean deliveries at less than 39 weeks, accounting for potential inaccuracies in pregnancy dating. Study Design We analyzed a cohort of repeat cesarean deliveries before and after the policy change and used chi-square testing to compare the proportion of deliveries at less than 39 weeks. We assessed whether the reduction in early-term deliveries was different if the gestational age was based on the documented estimated date of delivery (EDD) as compared with best obstetric dating. Results Our cohort consisted of 213 women; 112 before the policy change and 101 after. Using the EDD assigned at delivery, there was a 12.1% absolute decrease in scheduled deliveries at less than 39 weeks (25.0–12.9%; p = 0.025). However, using the EDD by best obstetric dating, there was no significant change (32.1–25.7%; p = 0.305). Of the 85 discrepant EDDs, providers were more likely to assign an earlier EDD (63.5%; p = 0.013). Conclusion Our institution's policy change led to a 12.1% absolute reduction in documented, scheduled early-term deliveries, however only a 6.4% absolute decline using best obstetric dating. Policy initiatives to reduce early-term deliveries should consider the source and accuracy of the assigned pregnancy dating.
Achieving Sustainable Irrigation Water Withdrawals: Global Impacts on Food Production and Land Use

Unsustainable water use challenges the capacity of water resources to ensure food security and continued growth of the economy. Adaptation policies targeting future water security can easily overlook its interaction with other sustainability metrics and unanticipated local responses to the larger-scale policy interventions. Using a global partial equilibrium grid-resolving model SIMPLE-G, and coupling it with the global Water Balance Model, we simulate the consequences of reducing unsustainable irrigation for food security, land use change, and terrestrial carbon. A variety of future (2050) scenarios are considered that interact irrigation productivity with two policy interventions— inter-basin water transfers and international commodity market integration. We find that pursuing sustainable irrigation may erode other development and environmental goals due to higher food prices and cropland expansion. This results in over 800 000 more undernourished people and 0.87 GtC additional emissions. Faster total factor productivity growth in irrigated sectors will encourage more aggressive irrigation water use in the basins where irrigation vulnerability is expected to be reduced by inter-basin water transfer. By allowing for a systematic comparison of these alternative adaptations to future irrigation vulnerability, the global gridded modeling approach offers unique insights into the multiscale nature of the water scarcity challenge.
The Volcker Rule as structural law: implications for cost–benefit analysis and administrative law

The Volcker rule, a key part of Congress’s response to the financial crisis, is best understood as a “structural law,” a traditional Anglo-American technique for governance of hybrid public-private institutions such as banks and central banks. The tradition extends much farther back in time than the Glass-Steagall Act, to which the Volcker Rule has been unfavorably (but unfairly) compared. The goals of the Volcker Rule are complex and ambitious, and not limited to reducing risk directly, but include reshaping banks’ organizational cultures. Another body of structural laws, part of the core of administrative law, attempts to restrain and discipline regulatory agencies, through process requirements such as cost-benefit analysis (CBA). Could the Volcker rule be the subject of reliable, precise, quantified CBA? Given the nature of the Volcker rule as structural law, its ambitions, and the current capacities of CBA, the answer is clearly “no,” as it would require regulators to anticipate, in advance of data, private market behavior in response to novel activity constraints. If administrative law is to improve regulatory implementation of structural laws such as the Volcker Rule, better fitting and more nuanced tools than CBA are needed.
Evaluating the impact of chemotherapy-induced peripheral neuropathy symptoms (CIPN-sx) on perceived ability to work in breast cancer survivors during the first year post-treatment

Purpose To describe the impact of chemotherapy-induced peripheral neuropathy symptoms (CIPN-sx) on breast cancer survivors’ (BCS) perceived ability to work post-treatment.
Maternal stress and birth outcomes: Evidence from the 1994 Northridge earthquake

Abstract Psychological maternal stress is thought to be a factor in poor infant health, but direct evidence is difficult to obtain. We posit that the 1994 Northridge earthquake in Los Angeles, California provides a natural test of the effect of mothers’ stress on infants’ birth weight and gestation. The Northridge disaster featured a low rate of injury and a quick recovery, but long-lasting and well documented consequences for mental health. Difference-in-difference results show that infants born closest to the epicenter were 0.2 percentage points more likely to be born with low birth weight. Impacts were larger and more precisely identified for women who experienced the earthquake in their first or third trimester. Among the subsample of mothers most susceptible to stress – first-time, single mothers – low birth weight was 0.5 percentage points more likely to occur. We find little evidence that the earthquake affected preterm delivery.
Fur trade archaeology: A study of frontier hierarchies

Zooarchaeological methods were used to examine status differences exhibited by two 19th century fur trading posts in northwestern Wisconsin (1802–1804). It was hypothesized that the well established North West Company Post would exhibit a higher standard of frontier living and hence, status, than that of the rival XY Company, and these differences should be reflected in the diet of the fur traders. Analysis indicates that the North West Company traders consumed a larger quantity and better quality of meat than their rivals. These data were also used, on an intrasite basis, to differentiate the occupants of the North West Company cabins. This examination yielded results which conflicted with previous interpretations, prompting a reexamination of the non-faunal data and rejection of the earlier interpretations.
The Core of the Participatory Budgeting Problem

In participatory budgeting, communities collectively decide on the allocation of public tax dollars for local public projects. In this work, we consider the question of fairly aggregating preferences to determine an allocation of funds to projects. We argue that the classic game theoretic notion of core captures fairness in the setting. To compute the core, we first develop a novel characterization of a public goods market equilibrium called the Lindahl equilibrium. We then provide the first polynomial time algorithm for computing such an equilibrium for a broad set of utility functions. We empirically show that the core can be efficiently computed for utility functions that naturally model data from real participatory budgeting instances, and examine the relation of the core with the welfare objective. Finally, we address concerns of incentives and mechanism design by developing a randomized approximately dominant-strategy truthful mechanism building on the Exponential Mechanism from differential privacy.
Pluggable scheduling for the reactor programming model

The reactor model is a foundational programming model for distributed computing, whose focus is modularizing and composing computations and message protocols. Previous work on reactors dealt mainly with the programming model and its composability properties, but did not show how to schedule computations in reactor-based programs. In this paper, we propose a pluggable scheduling algorithm for the reactor model. The algorithm is customizable with user-defined scheduling policies. We define and prove safety and progress properties. We compare our implementation against the Akka actor framework, and show up to 3× performance improvements on standard actor benchmarks.
False-Name-Proof Recommendations in Social Networks

We study the problem of finding a recommendation for an uninformed user in a social network by weighting and aggregating the opinions offered by the informed users in the network. In social networks, an informed user may try to manipulate the recommendation by performing a false-name manipulation, wherein the user submits multiple opinions through fake accounts. To that end, we impose a no harm axiom: false-name manipulations by a user should not reduce the weight of other users in the network. We show that this axiom has deep connections to false-name-proofness. While it is impossible to design a mechanism that is best for every network subject to this axiom, we propose an intuitive mechanism LEGIT+, and show that it is uniquely optimized for small networks. Using real-world datasets, we show that our mechanism performs very well compared to two baseline mechanisms in a number of metrics, even on large networks.
Effective medium model for multilayered anisotropic media with different orientations

Anisotropic property is very popular among modern engineering materials such as composites, fibers, crystals, wood and so on. These kinds of materials have a lot of usages as housings and casings in aerospace, transportation, civil infrastructure, electronics, appliance and marine. In aerospace industry, composites can be replacements for metals due to its good features that they are not as electrically conductive as traditional. It becomes more and more important to understand the electromagnetic interactions (i.e., reflection, transmission) of composites. Multilayered anisotropic material with different orientations is very common in composites. However, electromagnetic modelling of multilayered anisotropic material needs huge CPU time and memory requirements. Using effective medium theory, by replacing multilayered anisotropic medium with a single equivalent layer for the permittivity, permeability and orientation, CPU time and memory requirements can be significantly reduced. In this paper, effective medium theory is applied to model two-layer biaxial anisotropic material with different orientations. The reflection and transmission matrices are derived for both single and two layers of biaxial anisotropic materials for a plane wave incidence at the normal direction. Basing on the same reflection and transmission coefficients, effective anisotropic permittivity, permeability and orientation angle are extracted, similar to the approach used to extract effective parameters from measurements and numerical modeling of periodic structures as isotropic materials. With the low frequency (LF) limit, analytical expressions for effective parameters and orientation angle are derived and result in a frequency-independent equivalent model. The low frequency approximations also give a non-magnetic effective anisotropic model if each layer is non-magnetic anisotropic dielectric. Finally, effective parameters using low frequency approximation are compared with the ones from parameter extraction method. Good agreements in effective parameters and angle are observed between with and without the approximations for the frequency up to several GHz.
A new target for differentiation therapy in AML

Despite major advances in understanding the genetics and epigenetics of acute myelogenous leukemia, there is still a great need to develop more specific and effective therapies. High throughput approaches involving either genetic approaches or small molecule inhibitor screens are beginning to identify promising new therapeutic targets.
Retinopathy predicts progression of fasting plasma glucose: An Early Diabetes Intervention Program (EDIP) analysis.

Abstract Background Retinopathy is increasingly recognized in prediabetic populations, and may herald increased risk of metabolic worsening. The Early Diabetes Intervention Program (EDIP) evaluated worsening of glycemia in screen-detected Type 2 diabetes, following participants for up to 5 years. Here we have evaluated whether the presence of retinopathy at the time of detection of diabetes was associated with accelerated progression of glycemia. Methods We prospectively studied 194 participants from EDIP with available baseline retinal photographs. Retinopathy was determined at baseline using 7-field fundus photography and defined as an Early Treatment of Diabetic Retinopathy Study Scale grading score of ≥ 20. Results At baseline, 12% of participants had classical retinal lesions indicating retinopathy. In univariate Cox proportional hazard analysis, the presence of retinopathy at baseline was associated with a doubled risk of progression of fasting plasma glucose (HR 2.02; 95% CI 1.05–3.89). The retinopathy effect was robust to individual adjustment for age and glucose, the most potent determinants of progression in EDIP. Conclusion Retinopathy was associated with increased risk of progression of fasting plasma glucose among adults with screen-detected, early diabetes. Early detection of retinopathy may help individualize more aggressive therapy to prevent progressive metabolic worsening in early diabetes.
A population-induced renewable energy timeline in nine world regions

Abstract Approximately 1.1 billion people worldwide do not have access to electricity. The World Bank's Sustainable Energy for All initiative seeks to provide universal access to energy by the year 2030. The current world population of 7.3 billion is projected to reach 8.5 billion by 2030 and 11.2 billion by 2100. Population growth and increasing energy access are incongruous with forecasts of declining non-renewable energy production and climate change concerns. Previous studies have examined these issues at global or at individual regional or national levels. Here we use a nine region model of the world with two per capita energy consumption scenarios to find that significant restructuring of the current energy mix will be necessary in order to support population projections. Modelled interaction between the regions highlights the importance of examining energy and population concerns in a systemic manner, as each of the nine regions faces unique energy-population challenges in the coming decades. As non-renewable energy reserves decline globally, the transition to a renewable energy infrastructure will develop at different times in each region.
Avoiding the Pitfalls of Net Uniformity: Zero Rating and Nondiscrimination

The current debate over network neutrality has not fully appreciated how service differentiation can benefit consumers and promote Internet adoption. On the demand-side, service differentiation addresses the primary obstacle to adoption, which is the lack of perceived need for Internet service, and reflects the growing heterogeneity of consumer demand. On the supply-side, monopolistic competition has long underscored how product differentiation can create stable equilibria with multiple providers—notwithstanding the presence of unexhausted economies of scale—by allowing competitors to target subsegments of the overall market that place a higher value on particular services. Conversely, prohibiting service differentiation would restrict competition to price and network size, which are factors that favor the largest players. These dynamics are well illustrated by global enforcement patterns with respect to a practice known as “zero rating”, which permits subscribers to access certain content without having that traffic count against their data caps. Of the six countries that have brought enforcement actions against zero rating, only India has categorically banned the practice. The other five countries (the United States, Chile, Canada, Slovenia, and The Netherlands) have adopted a more nuanced approach. A case-by-case approach is consistent with the empirical literature on vertical integration and restraints and the well-established principles for determining when to impose per se illegality and when to apply the “rule of reason”. The U.S. Supreme Court’s antitrust jurisprudence also helps identify factors that militate against liability, such as the lack of market power, nonexclusivity, and nonproprietary services.
Pseudospectral methods for optimal motion planning of differentially flat systems

The article presents some preliminary results on combining two new ideas from nonlinear control theory and dynamic optimization. We show that the computational framework facilitated by pseudospectral methods applies quite naturally and easily to Fliess' implicit state variable representation of dynamical systems. The optimal motion planning problem for differentially flat systems is equivalent to a classic Bolza problem of the calculus of variations. We exploit the notion that derivatives of flat outputs given in terms of Lagrange polynomials at Legendre-Gauss-Lobatto points can be quickly computed using pseudospectral differentiation matrices. Additionally, the Legendre pseudospectral method approximates integrals by Gauss-type quadrature rules. The application of this method to the two-dimensional crane model reveals how differential flatness may be readily exploited.
Traceability of No-Load Loss Measurements of High-Voltage Transmission Lines

This paper describes the traceable measurement of no-load losses of high-voltage transmission lines, including actual no-load loss measurements of 220-kV transmission lines in coastal Peru. The measurement methodology and the evaluation of the no-load losses are discussed in this paper. The development of a new measurement methodology to allow for future live line connections is also described.
INTRANSITIVITY AND VAGUENESS

There are many examples in the literature that suggest that indistinguishability is intransitive, despite the fact that the indistinguishability relation is typically taken to be an equivalence relation (and thus transitive). It is shown that if the uncertainty perception and the question of when an agent reports that two things are indistinguishable are both carefully modeled, the problems disappear, and indistinguishability can indeed be taken to be an equivalence relation. Moreover, this model also suggests a logic of vagueness that seems to solve many of the problems related to vagueness discussed in the philosophical literature. In particular, it is shown here how the logic can handle the sorites paradox.
The role of probability-based inference in an intelligent tutoring system

Probability-based inference in complex networks of interdependent variables is an active topic in statistical research, spurred by such diverse applications as forecasting, pedigree analysis, troubleshooting, and medical diagnosis. This paper concerns the role of Bayesian inference networks for updating student models in intelligent tutoring systems (ITSs). Basic concepts of the approach are briefly reviewed, but the emphasis is on the considerations that arise when one attempts to operationalize the abstract framework of probability-based reasoning in a practical ITS context. The discussion revolves around HYDRIVE, an ITS for learning to troubleshoot an aircraft hydraulics system. HYDRIVE supports generalized claims about aspects of student proficiency through probabilitybased combination of rule-based evaluations of specific actions. The paper highlights the interplay among inferential issues, the psychology of learning in the domain, and the instructional approach upon which the ITS is based.
Enhancing low severity coal liquefaction reactivity using mild chemical pretreatment

Abstract We describe results from a study in which mild chemical pretreatment of coal has been used to enhance low severity liquefaction reactivity. We have found that ambient pretreatment of eight Argonne coals using methanol and a trace amount of hydrochloric acid improves tetrahydrofuran (THF)-soluble conversions by 24.5 wt% (daf basis) for Wyodak subbituminous coal and 28.4 wt% for Beulah-Zap lignite with an average increase of 14.9 wt% for liquefaction of the eight coals at 623 K (350 °C) reaction temperature and 30 min reaction time. Similar enhancement results occurred using hexane or acetone in place of methanol. Pretreatment with methanol and HCl separately indicated that both reagents were necessary to achieve maximum liquefaction improvement. Acid concentration was the most important pretreatment variable studied; liquefaction reactivity increased with increasing acid concentration up to 2vol%. No appreciable effect on reactivity was observed at higher acid concentrations. Although vapour phase alcohol/HCl mixtures have been shown to partially alkylate bituminous coals, analysis of Wyodak and Illinois no. 6 coal samples indicated that no organic phase alteration occurred during pretreatment; however, over 90 wt% of the calcium was removed from each coal. Calcium is thought to catalyse retrogressive reactions during coal pyrolysis, and thus calcium removal prior to low severity liquefaction minimizes the rate of THF-insoluble product formation.
Software for exact integration of polynomials over polyhedra

We are interested in the fast computation of the exact value of integrals of polynomial functions over convex polyhedra. We present speed-ups and extensions of the algorithms presented in previous work by some of the authors. We provide a new software implementation and benchmark computations. The computation of integrals of polynomials over polyhedral regions has many applications; here we demonstrate our algorithmic tools solving a challenge from combinatorial voting theory.
Interface trapping in unipolar space-charge-limited current

It is assumed almost invariably in the literature that traps, when present, are distributed uniformly in the bulk of a device. But in unipolar space-charge-limited current (sclc) charge carrier traps suppress current most efficiently when located in the immediate vicinity of the emitter. A new model is developed, therefore, which accounts for this result by assuming that the traps responsible for the current suppression are located at the emitter interface in a surface concentration Σ while the bulk remains free of traps. The analysis has been carried out for traps with one discrete trapping level E t below the edge E b of the conducting band and for the five distinct cases of planar, cylindrical, and spherical configuration. The main results are: (a) The V-I characteristic exhibits the V TFL typical to many experimental results. (b) The relevant parameter is the ratio rN/ \Sigma \exp ((E_{b} - E_{t})/kT) , where r is a length characteristic of the geometrical configuration of the device and N is the effective density of states of the conducting band. (c) For a semispherical emitter ("point contact") unipolar sclc dominated by interface trapping is essentially independent on sample dimensions.
Robust sequential change-point detection by convex optimization

We address the computational challenge of finding the robust sequential change-point detection procedures when the pre- and post-change distributions are not completely specified. Earlier works [1], [2] establish the general conditions for robust procedures which include finding a pair of least favorable distributions (LFDs). However, in the multi-dimensional setting, it is hard to find such LFDs computationally. We present a method based on convex optimization that addresses this issue when the distributions are Gaussian with unknown parameters from pre-specified uncertainty sets. We also establish theoretical properties of our robust procedures, and numerical examples demonstrate their good performance1.
Orbit uncertainty propagation and sensitivity analysis with separated representations

Most approximations for stochastic differential equations with high-dimensional, non-Gaussian inputs suffer from a rapid (e.g., exponential) increase of computational cost, an issue known as the curse of dimensionality. In astrodynamics, this results in reduced accuracy when propagating an orbit-state probability density function. This paper considers the application of separated representations for orbit uncertainty propagation, where future states are expanded into a sum of products of univariate functions of initial states and other uncertain parameters. An accurate generation of separated representation requires a number of state samples that is linear in the dimension of input uncertainties. The computation cost of a separated representation scales linearly with respect to the sample count, thereby improving tractability when compared to methods that suffer from the curse of dimensionality. In addition to detailed discussions on their construction and use in sensitivity analysis, this paper presents results for three test cases of an Earth orbiting satellite. The first two cases demonstrate that approximation via separated representations produces a tractable solution for propagating the Cartesian orbit-state uncertainty with up to 20 uncertain inputs. The third case, which instead uses Equinoctial elements, reexamines a scenario presented in the literature and employs the proposed method for sensitivity analysis to more thoroughly characterize the relative effects of uncertain inputs on the propagated state.
Equational formulas and pattern operations in initial order-sorted algebras

A patternt, i.e., a term possibly with variables, denotes the set (language) $${\llbracket t \rrbracket}$$źtź of all its ground instances. In an untyped setting, symbolic operations on finite sets of patterns can represent Boolean operations on languages. But for the more expressive patterns needed in declarative languages supporting rich type disciplines such as subtype polymorphism, untyped pattern operations and algorithms break down. We show how they can be properly defined by means of a signature transformation $${\Sigma \mapsto \Sigma^{\#}}$$ΣźΣ# that enriches the types of $${\Sigma}$$Σ. We also show that this transformation allows a systematic reduction of the first-order logic properties of an initial order-sorted algebra supporting subtype-polymorphic functions to equivalent properties of an initial many-sorted (i.e., simply typed) algebra. This yields a new, simple proof of the known decidability of the first-order theory of an initial order-sorted algebra.
A Bound on Partitioning Clusters

Let $X$ be a finite collection of sets (or "clusters"). We consider the problem of counting the number of ways a cluster $A \in X$ can be partitioned into two disjoint clusters $A_1, A_2 \in X$, thus $A = A_1 \uplus A_2$ is the disjoint union of $A_1$ and $A_2$; this problem arises in the run time analysis of the ASTRAL algorithm in phylogenetic reconstruction. We obtain the bound $$ | \{ (A_1,A_2,A) \in X \times X \times X: A = A_1 \uplus A_2 \} | \leq |X|^{3/p} $$ where $|X|$ denotes the cardinality of $X$, and $p := \log_3 \frac{27}{4} = 1.73814\dots$, so that $\frac{3}{p} = 1.72598\dots$. Furthermore, the exponent $p$ cannot be replaced by any larger quantity. This improves upon the trivial bound of $|X|^2$. The argument relies on establishing a one-dimensional convolution inequality that can be established by elementary calculus combined with some numerical verification. In a similar vein, we show that for any subset $A$ of a discrete cube $\{0,1\}^n$, the additive energy of $A$ (the number of quadruples $(a_1,a_2,a_3,a_4)$ in $A^4$ with $a_1+a_2=a_3+a_4$) is at most $|A|^{\log_2 6}$, and that this exponent is best possible.
CERAMIC-CERAMIC THA IN PATIENTS <60: A NEW STANDARD – AFFIRMS

While total hip arthroplasty (THA) has been shown successful at relieving pain and improving function in patients with coxarthrosis, wear and instability remain leading causes for revision surgery. Highly crosslinked polyethylene (HXPE) has significantly reduced wear and osteolysis but volumetric wear associated with the use of larger diameter ball heads may be an issue in the long-term. Finally, concerns with femoral taper corrosion have increased the utilization of ceramic ball heads in recent years. Ceramic on ceramic articulations are optimised for both minimizing implant wear and instability. It is biocompatible, wettable, and possesses the lowest in vitro and in vivo wear rates among all bearing couples. In fact, wear rates are lowest when the ceramic ball head size is maximised. Additionally, modern ceramic on ceramic THA designs have had an excellent clinical track record with low rates of loosening, failure, and no reports of osteolysis in even highly active, young patients. Concerns with ceramics center around issues related to fracture risk, squeaking, and cost. While the phenomenon of squeaking remains poorly understood, the reliability of ceramic implants have steadily improved with better materials, design, and manufacturing. The fracture risk for modern pure alumina implants and the newer alumina matrix composite ceramics are 1 in 5000 and 1 in 100,000, respectively. The advantages of ceramic on ceramic THAs will not be realised on every patient and therefore, should be selectively used. However, with expected increases in life expectancy and more young, active patients undergoing THA, ceramic on ceramic THA should be strongly considered in patients under age 60 years.
Higher-order accurate space-time schemes for computational astrophysics—Part I: finite volume methods

As computational astrophysics comes under pressure to become a precision science, there is an increasing need to move to high accuracy schemes for computational astrophysics. The algorithmic needs of computational astrophysics are indeed very special. The methods need to be robust and preserve the positivity of density and pressure. Relativistic flows should remain sub-luminal. These requirements place additional pressures on a computational astrophysics code, which are usually not felt by a traditional fluid dynamics code. Hence the need for a specialized review. The focus here is on weighted essentially non-oscillatory (WENO) schemes, discontinuous Galerkin (DG) schemes and PNPM schemes. WENO schemes are higher order extensions of traditional second order finite volume schemes. At third order, they are most similar to piecewise parabolic method schemes, which are also included. DG schemes evolve all the moments of the solution, with the result that they are more accurate than WENO schemes. PNPM schemes occupy a compromise position between WENO and DG schemes. They evolve an Nth order spatial polynomial, while reconstructing higher order terms up to Mth order. As a result, the timestep can be larger. Time-dependent astrophysical codes need to be accurate in space and time with the result that the spatial and temporal accuracies must be matched. This is realized with the help of strong stability preserving Runge–Kutta schemes and ADER (Arbitrary DERivative in space and time) schemes, both of which are also described. The emphasis of this review is on computer-implementable ideas, not necessarily on the underlying theory.