cssi/SciSciGPT-SciSciNet huggingface dataset:
Radical mediated C-H functionalization of 3,6-dichloropyridazine: efficient access to novel tetrahydropyridopyridazines.

A radical mediated C–H functionalization of 3,6-dichloropyridazine using primary alcohols, t-BuOOH, and TiCl3 to access alkoxy pyridazines is described. This transformation is conducted open to air and on gram scale. A subsequent cyclization step can then be employed to efficiently access diversely substituted tetrahydropyridopyridazines with multiple functional handles.
The Contribution of Internal Energy to the Elastic Force of Natural Rubber

Data are reported for the temperature coefficient of the retractive force for a natural rubber sample which had been crosslinked by irradiation. These measurements differ from those previously reported in allowing a longer interval for the attainment of equilibrium, in covering a wider range of elongations, and in a somewhat greater precision of the tension measurement. The Mooney equation constants for the tension at 45°C. are 2C1 = 2.617 kg./cm.2 and 2C2 = 0.876 kg./cm.2. The latter, although smaller than the values reported by other workers for similar samples, is far from vanishing. A comparison is given of (∂f/∂T)V,L as evaluated from the measured (∂f/∂T)V,L according to various proposals. Approximately 20% of the total force arises from the internal energy contribution, fe, when the relative elongation, α, is near unity. The fe/f ratios calculated from our measurements stand in good agreement with those obtained from Ciferri's data, despite the fact that the latter correspond to a much larger C2 value. Furthermore, both sets of data indicate that fe/f decreases with increasing α. The entropy component of the force, when fitted to the Mooney equation, yields C1s ≅ C1 but C2s < C2. This suggests that the C1 term is primarily due to entropy effects, whereas the internal energy makes a larger contribution to C2. The nonvanishing C2 and the variation of the fe/f ratio with α, represent deviations from the gaussian model treatment of Flory, Hoeve, and Ciferri. Criferri and Flory have expressed the opinion that finite C2 values arise solely from the failure to attain mechanical equilibrium. However, the cubic lattice model treatment of Krigbaum and Kaneko indicated that although the two discrepancies cited above may be accentuated by nonequilibrium effects, they can only be expected to vanish under equilibrium conditions in the limit of infinite chain length between crosslinks.
HETEROTOPIC BONE: MORE OR LESS OF AN ISSUE IN 2012?

The incidence of clinically significant (Brooker stage 3–4) heterotopic ossification (HO) after THA is 3–7%. Risk factors include male gender, old age, a history of HO, Paget9s disease, post-traumatic arthritis, osteonecrosis and rheumatoid arthritis. Prophylaxis for high-risk patients consists of 1) radiotherapy given as one dose of 7–8 Gy either pre-operatively (
Elderly patients undergoing SBRT for inoperable early-stage NSCLC achieve similar outcomes to younger patients.

Abstract Objectives It is unclear whether elderly patients face an increased risk of complications following stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer (NSCLC), as has been reported following surgical resection. This study evaluates toxicity and outcomes achieved with SBRT in elderly versus non-elderly patients. Materials and methods We retrospectively identified patients treated with SBRT for cT1-3N0M0 NSCLC between 2007 and 2013. We defined elderly and non-elderly cohorts by age ≥75 and Results We identified 251 patients (126 elderly, 125 non-elderly) with a median follow-up of 3.0 years. No differences in acute or late grade ≥3 toxicity were observed. Acute grade ≥3 toxicity was 11.1% in elderly vs. 8.0% in non-elderly ( p =0.66). Late grade ≥3 toxicity was 10.3% in elderly vs. 7.2% in non-elderly ( p =0.50). There was one grade 5 toxicity (hemoptysis). There were no 3-year OS or LC differences between elderly and non-elderly patients (OS 47.5% vs. 41.0%, p =0.75; LC 84.2% vs. 86.4%, p =0.89). However, 3-year DC was superior in elderly patients (89.1% vs. 76.0%, p =0.01). Improved DC remained associated with elderly age in Cox regression (HR 0.42, p =0.01). Conclusion Elderly patients undergoing SBRT for early stage NSCLC appear to have similar risk of toxicity and rate of efficacy as in younger patients. These findings support the use of SBRT in appropriately selected elderly patients.
Optimal designs for longitudinal and functional data

Summary We propose novel optimal designs for longitudinal data for the common situation where the resources for longitudinal data collection are limited, by determining the optimal locations in time where measurements should be taken. As for all optimal designs, some prior information is needed to implement the optimal designs proposed. We demonstrate that this prior information may come from a pilot longitudinal study that has irregularly measured and noisy measurements, where for each subject one has available a small random number of repeated measurements that are randomly located on the domain. A second possibility of interest is that a pilot study consists of densely measured functional data and one intends to take only a few measurements at strategically placed locations in the domain for the future collection of similar data. We construct optimal designs by targeting two criteria: optimal designs to recover the unknown underlying smooth random trajectory for each subject from a few optimally placed measurements such that squared prediction errors are minimized; optimal designs that minimize prediction errors for functional linear regression with functional or longitudinal predictors and scalar responses, again from a few optimally placed measurements. The optimal designs proposed address the need for sparse data collection when planning longitudinal studies, by taking advantage of the close connections between longitudinal and functional data analysis. We demonstrate in simulations that the designs perform considerably better than randomly chosen design points and include a motivating data example from the Baltimore Longitudinal Study of Aging. The designs are shown to have an asymptotic optimality property.
Pathways to retirement: patterns of labor force participation and labor market exit among the pre-retirement population by race, Hispanic origin, and sex.

Objectives This study examines the pre-retirement labor force participation behavior of Black, White, and Hispanic men and women to determine how patterns of labor market exit differ among groups. Methods We combine data from the first and second waves of the Health and Retirement Study and apply multinomial logit regression techniques to model labor force status in the first wave of the HRS and change over time. Results Black, Hispanic, and female elderly persons experience more involuntary job separation in the years immediately prior to retirement, and the resulting periods of joblessness often eventuate in "retirement" or labor force withdrawal. Minority disadvantage in human capital, health, and employment characteristics accounts for a large part of racial and ethnic differences in labor force withdrawal. Nevertheless, Black men and Hispanic women experience more involuntary labor market exits than Whites with similar socioeconomic and demographic characteristics. Discussion Workers most vulnerable to labor market difficulties during their youth confront formidable obstacles maintaining their desired level of labor force attachment as they approach their golden years. This has significant policy implications for the contours of gender and race/ethnic inequality among elderly persons, particularly as life expectancy and the size of the minority elderly population continue to increase.
Firm efficiency, advertising and profitability: Theory and evidence

Abstract This paper presents a linear-city model where firms compete on price and levels of advertising, which affects the perceived utility of products. More cost efficient firms extend their advantage with more advertising, which leads to higher profits, if advertising is sufficiently effective. We test this relationship using a unique S&P sample. Our empirical results indicate a positive relationship between profits and levels of advertising for all model specifications.
Resolving Conflicts Between Endangered Species Conservation and Renewable Energy Siting: Wiggle Room for Renewables?

ABSTRACTTwo federal policies—the protection of endangered species, and the rapid creation of a renewable energy infrastructure—currently exist in significant legal tension. While both are important for the development of necessary sustainability, climate change induced by the continuous burning of carbon-based fuels likely poses a greater threat to endangered species than does the growth of commercial-scale renewable energy sites. This article outlines several points of conflict between the two policies and subsequently considers the extent to which federal agencies responsible for renewable energy oversight and development possess wiggle room under the Endangered Species Act. A few recommendations for greater leeway are then offered.
An analysis of firms' sustainable operations strategies: a game theory approach

Environmental sustainability is receiving increasing attention in industries and is manifested in various dimensions such as marketing and operations. Incorporating sustainability in operations is a strategic decision that has challenged most firms in recent years. Social trends and government regulations are important factors that play a role in influencing firms' decisions to adopt an environmentally sustainable strategy in their operations. In this paper, we develop a game theory model to mathematically analyse how these two factors can change a firm's decision from a non-sustainable to a sustainable strategy, and vice versa. We demonstrate that the model is not limited to the 'prisoner's dilemma' but also includes the games of 'harmony' and 'no-conflict'. This model helps explain firms' past sustainability behaviour and enables us to predict their future actions.
Towards a Characterization of Approximation Resistance for Symmetric CSPs

A Boolean constraint satisfaction problem (CSP) is called approximation resistant if independently setting variables to 1 with some probability α achieves the best possible approximation ratio for the fraction of constraints satisfied. We study approximation resistance of a natural subclass of CSPs that we call Symmetric Constraint Satisfaction Problems (SCSPs), where satisfaction of each constraint only depends on the number of true literals in its scope. Thus a SCSP of arity k can be described by a subset S⊆ {0,1, . . . ,k} of allowed number of true literals. For SCSPs without negation, we conjecture that a simple sufficient condition to be approximation resistant by Austrin and Hastad is indeed necessary. We show that this condition has a compact analytic representation in the case of symmetric CSPs (depending only on the gap between the largest and smallest numbers in S), and provide the rationale behind our conjecture. We prove two interesting special cases of the conjecture, (i) when S is an interval (i.e., S = {i | l 6 i 6 r} for some l 6 r) and (ii) when S is even (i.e., s ∈ S⇔ k− s ∈ S). For SCSPs with negation, we prove that the analogous sufficient condition by Austrin and Mossel is necessary for the same two cases, though we do not pose an analogous conjecture in general. ∗Supported in part by NSF grant CCF-1115525. guruswami@cmu.edu †Supported by a Samsung Fellowship and NSF CCF-1115525. euiwoonl@cs.cmu.edu ISSN 1433-8092 Electronic Colloquium on Computational Complexity, Report No. 105 (2015)
The implementation of low-cost urban acoustic monitoring devices

Abstract The urban sound environment of New York City (NYC) can be, amongst other things: loud, intrusive, exciting and dynamic. As indicated by the large majority of noise complaints registered with the NYC 311 information/complaints line, the urban sound environment has a profound effect on the quality of life of the city’s inhabitants. To monitor and ultimately understand these sonic environments, a process of long-term acoustic measurement and analysis is required. The traditional method of environmental acoustic monitoring utilizes short term measurement periods using expensive equipment, setup and operated by experienced and costly personnel. In this paper a different approach is proposed to this application which implements a smart, low-cost, static, acoustic sensing device based around consumer hardware. These devices can be deployed in numerous and varied urban locations for long periods of time, allowing for the collection of longitudinal urban acoustic data. The varied environmental conditions of urban settings make for a challenge in gathering calibrated sound pressure level data for prospective stakeholders. This paper details the sensors’ design, development and potential future applications, with a focus on the calibration of the devices’ Microelectromechanical systems (MEMS) microphone in order to generate reliable decibel levels at the type/class 2 level.
Estimating the annual volume of hematologic cancer cases per hematologist–oncologist in the United States: are we treating rare cancers too rarely?

Among all malignancies, hematologic cancers are perhaps the most challenging to manage in clinical practice due to their relative rarity, broad diversity, and ever-growing complexity. Even though h...
Implications of Small Samples for Generalization: Adjustments and Rules of Thumb.

Background:Policy makers and researchers are frequently interested in understanding how effective a particular intervention may be for a specific population. One approach is to assess the degree of...
Founded semantics and constraint semantics of logic rules

Logic rules and inference are fundamental in computer science and have been studied extensively. However, prior semantics of logic languages can have subtle implications and can disagree significantly, on even very simple programs, including in attempting to solve the well-known Russell's paradox. These semantics are often non-intuitive and hard-to-understand when unrestricted negation is used in recursion. This paper describes a simple new semantics for logic rules, founded semantics, and its straightforward extension to another simple new semantics, constraint semantics, that unify the core of different prior semantics. The new semantics support unrestricted negation, as well as unrestricted existential and universal quantifications. They are uniquely expressive and intuitive by allowing assumptions about the predicates, rules, and reasoning to be specified explicitly, as simple and precise binary choices. They are completely declarative and relate cleanly to prior semantics. In addition, founded semantics can be computed in linear time in the size of the ground program.
Model Images of Radio Halos around Supernova Remnants

I present model calculations of profiles and two-dimensional images of the radio synchrotron emission of young supernova remnants, concentrating on observable effects of relativistic eletrons diffusing upstream of the shock wave. If the preshock electron scattering mean free path is sufficiently long, observable synchrotron halos outside the bulk of the radio emission can potentially result; their absence can constrain the mean free path from above. If scattering is primarily due, as expected, to Alfven waves with amplitude detla(B), the halo is expected to extend a distance of order r(sub g)c(delta(B)/B)(exp 2)/v(sub s) beyond the shock, where r(sub g) is the gyroradius of the electrons emitting at the observed frequency, B is the upstream magnetic field strength, v(sub s) is the shock velocity, and the amplitude delta(B) refers to wave with wavelength comparable to r(sub g), of order 10(exp 13) cm for typical supernova-remnant parameters. However, the detailed geometry of the halo varies with the assumptions about particle acceleration in the shock wave. I present an atlas of model profiles and images as a function of preshock diffusion length, of aspect angle between the magnetic field and the line of sight, and of other relevant parameters.
Valley blockade in a silicon double quantum dot

Electrical transport in double quantum dots (DQDs) illuminates many interesting features of the dots' carrier states. Recent advances in silicon quantum information technologies have renewed interest in the valley states of electrons confined in silicon. Here we show measurements of dc transport through a mesa-etched silicon double quantum dot. Comparing bias triangles (i.e., regions of allowed current in DQDs) at positive and negative bias voltages we find a systematic asymmetry in the size of the bias triangles at the two bias polarities. Asymmetries of this nature are associated with blocked tunneling events due to the occupation of a metastable state. Several features of our data lead us to conclude that the states involved are not simple spin states. Rather, we develop a model based on selective filling of valley states in the DQD that is consistent with all of the qualitative features of our data.
Ego2Top: Matching Viewers in Egocentric and Top-View Videos

Egocentric cameras are becoming increasingly popular and provide us with large amounts of videos, captured from the first person perspective. At the same time, surveillance cameras and drones offer an abundance of visual information, often captured from top-view. Although these two sources of information have been separately studied in the past, they have not been collectively studied and related. Having a set of egocentric cameras and a top-view camera capturing the same area, we propose a framework to identify the egocentric viewers in the top-view video. We utilize two types of features for our assignment procedure. Unary features encode what a viewer (seen from top-view or recording an egocentric video) visually experiences over time. Pairwise features encode the relationship between the visual content of a pair of viewers. Modeling each view (egocentric or top) by a graph, the assignment process is formulated as spectral graph matching. Evaluating our method over a dataset of 50 top-view and 188 egocentric videos taken in different scenarios demonstrates the efficiency of the proposed approach in assigning egocentric viewers to identities present in top-view camera. We also study the effect of different parameters such as the number of egocentric viewers and visual features.
Evolving energy enterprise-"Grand challenges": possible road ahead and challenges for R&D

A new mega-infrastructure is emerging from the convergence of energy (including the electric grid, water, oil and gas pipelines), telecommunications, transportation., Internet and electronic commerce. Furthermore, in the electric power industry and other critical infrastructures, new ways are being sought to improve network efficiency and eliminate congestion problems without seriously diminishing reliability and security. From a viewpoint of strategic research and development, there are many scientific and technological challenges posed by the lack of a unified framework with robust tools for monitoring, modeling, simulation, control and optimization of time-critical operations in hybrid, complex, distributed and interactive networks with multi-scale and multiple components. Secure and reliable operation of complex energy supply and delivery networks poses significant theoretical and practical challenges in sensing, communications, analysis, modeling, simulation, prediction, control, optimization, operations, and management.
Color-factor symmetry and BCJ relations for QCD amplitudes

Tree-level n-point gauge-theory amplitudes with n − 2k gluons and k pairs of (massless or massive) particles in the fundamental (or other) representation of the gauge group are invariant under a set of symmetries that act as momentum-dependent shifts on the color factors in the cubic decomposition of the amplitude. These symmetries lead to gauge-invariant constraints on the kinematic numerators. They also directly imply the BCJ relations among the Melia-basis primitive amplitudes previously obtained by Johansson and Ochirov.
The Influence of PBL Parameterization on the Practical Predictability of Convection Initiation during the Mesoscale Predictability Experiment (MPEX)

AbstractThis study evaluates the influence of planetary boundary layer parameterization on short-range (0–15 h) convection initiation (CI) forecasts within convection-allowing ensembles that utilize subsynoptic-scale observations collected during the Mesoscale Predictability Experiment. Three cases, 19–20 May, 31 May–1 June, and 8–9 June 2013, are considered, each characterized by a different large-scale flow pattern. An object-based method is used to verify and analyze CI forecasts. Local mixing parameterizations have, relative to nonlocal mixing parameterizations, higher probabilities of detection but also higher false alarm ratios, such that the ensemble mean forecast skill only subtly varied between parameterizations considered. Temporal error distributions associated with matched events are approximately normal around a zero mean, suggesting little systematic timing bias. Spatial error distributions are skewed, with average mean (median) distance errors of approximately 44 km (28 km). Matched event c...
Perturbative and nonperturbative aspects of complex Chern-Simons theory

We present an elementary review of some aspects of Chern-Simons theory with complex gauge group SL(N,C). We discuss some of the challenges in defining the theory as a full-fledged TQFT, as well as some successes inspired by the 3d-3d correspondence. The 3d-3d correspondence relates partition functions (and other aspects) of complex Chern-Simons theory on a 3-manifold M to supersymmetric partition functions (and other observables) in an associated 3d theory T[M]. Many of these observables may be computed by supersymmetric localization. We present several prominent applications to 3-manifold topology and number theory in light of the 3d-3d correspondence.
Teacher stress, teaching-efficacy, and job satisfaction in response to test-based educational accountability policies

Abstract Educator stress has been linked to decreased job satisfaction, negative instructional practices, and poor student outcomes. However, it is unknown whether educators with high teaching efficacy may better cope with the test stress. As such, the primary purpose of the present investigation was to examine the complex relationship between teacher self-efficacy, teacher stress related to testing, and job satisfaction. Structural equation modeling was used to evaluate the hypothesized relationships within a sample of 1242 teachers in one state in the Southeastern United States. Results indicated a significant influence of self-efficacy in student engagement and self-efficacy in classroom management on the relationship between sources of stress and job satisfaction, as well as efficacy in classroom management on the relationship between manifestations of stress and job satisfaction was also identified. These initial findings underscore the importance of supporting teacher self-efficacy to reduce stress associated with high-stakes accountability policies and increase job satisfaction. Implications and directions for future research will be discussed.
A 15-YEAR EXPERIENCE FROM SPECIALIST PHYSIOTHERAPY NORMAL VARIANT CLINICS: CLINICALLY EFFECTIVE AND COST EFFECTIVE

We present a review of our Specialist Physiotherapy clinic for normal physiological variations of the lower limb (SPNV) clinics, demonstrating them to be clinically effective and cost effective. Children with normal variation of rotational profile and limb angulation present much anxiety to parents and primary care. Providing consultation: to eliminate significant pathology and reassure families, is an important service that a Paediatric Orthopaedic department provides. In our tertiary referral department we have a Specialist Physiotherapy led clinics into which primary care practitioners refer children with whom there are concerns about lower limb development variation. The (SPNV) Clinic was first set up by a Consultant and Senior Physiotherapist in 1999. The aim of the clinic was to reduce the waiting times for incoming referrals but ensuring they are seen in an appropriate environment by an experienced health care professional. Clinics are run by Senior Specialist Physiotherapists, alongside Consultant clinics who are available for advice and direction. This provides security for the physios, the Trust and the patient. Over 15 years there have been more than 4000 patient visits to this clinic. Over 80% were new patient visits. 70% of these visits were discharged in one or two reviews. 97.4% of new referrals were discharged without subsequent review by an orthopaedic surgeon. The most common conditions reviewed were Genu valgum (25%), Genu Varum (16%), intoeing (17%) and flexible flat feet (11%). The clinic has proven to be cost effective as well in drawing in up to £500,000 revenue into the trust in a single year. The department has been approached by other trusts to assist in the implementation of similar clinics. We present this review of the patients, as a template for supporting the work of Paediatric Orthopaedic Departments. This service has facilitated the streamlining of our Consultant Paediatric Orthopaedic clinics.
Topological Magnon Bands and Unconventional Superconductivity in Pyrochlore Iridate Thin Films.

We theoretically study the magnetic properties of pyrochlore iridate bilayer and trilayer thin films grown along the [111] direction using a strong coupling approach. We find the ground state magnetic configurations on a mean field level and carry out a spin-wave analysis about them. In the trilayer case the ground state is found to be the all-in--all-out (AIAO) state, whereas the bilayer has a deformed AIAO state. For all parameters of the spin-orbit coupled Hamiltonian we study, the lowest magnon band in the trilayer case has a nonzero Chern number. In the bilayer case we also find a parameter range with nonzero Chern numbers. We calculate the magnon Hall response for both geometries, finding a striking sign change as a function of temperature. Using a slave-boson mean-field theory we study the doping of the trilayer system and discover an unconventional time-reversal symmetry broken $d+id$ superconducting state. Our study complements prior work in the weak coupling limit and suggests that the [111] grown thin film pyrochlore iridates are a promising candidate for topological properties and unconventional orders.
An M-channel critically sampled filter bank for graph signals

We investigate an M-channel critically sampled filter bank for graph signals where each of the M filters is supported on a different subband of the graph Laplacian spectrum. We partition the graph vertices such that the mth set comprises a uniqueness set for signals supported on the mth subband. For analysis, the graph signal is filtered on each subband and downsampled on the corresponding set of vertices. However, the classical synthesis filters are replaced with interpolation operators, circumventing the issue of how to design a downsampling pattern and graph spectral filters to ensure perfect reconstruction for signals that do not reside on bipartite graphs. The resulting transform is critically sampled and graph signals are perfectly reconstructable from their analysis coefficients. We empirically explore the joint vertex-frequency localization of the dictionary atoms and sparsity of the analysis coefficients, as well as the ability of the proposed transform to compress piecewise-smooth graph signals.
Does Communist party membership pay? Estimating the economic returns to party membership in the labor market in China

Abstract Many studies have found that Chinese Communist party membership brings economic benefits to party members, but some studies also argue that the premium associated with party membership is merely due to members’ higher levels of ability and advantageous family backgrounds. The lack of consensus on the economic returns of party membership implies that the role of party membership is not well understood. This study estimates the economic returns to Chinese Communist party membership using complementary approaches to address the endogeneity of party membership status: propensity score matching and instrumental variable. Although the magnitudes of these estimates vary across estimators, all the estimates show positive economic returns to party membership. This paper also examines possible mechanisms for how party membership may bring benefits to members and provides evidence that party membership may generate political capital, but not social capital in the labor market in China.
Lessons Learned When Introducing Pharmacogenomic Panel Testing into Clinical Practice.

Abstract Objectives Implementing new programs to support precision medicine in clinical settings is a complex endeavor. We describe challenges and potential solutions based on the Indiana GENomics Implementation: an Opportunity for the Underserved (INGenious) program at Eskenazi Health—one of six sites supported by the Implementing GeNomics In pracTicE network grant of the National Institutes of Health/National Human Genome Research Institute. INGenious is an implementation of a panel of genomic tests. Methods We conducted a descriptive case study of the implementation of this pharmacogenomics program, which has a wide scope (14 genes, 27 medications) and a diverse population (patients who often have multiple chronic illnesses, in a large urban safety-net hospital and its outpatient clinics). Challenges We placed the clinical pharmacogenomics implementation challenges into six categories: patient education and engagement in care decision making; clinician education and changes in standards of care; integration of technology into electronic health record systems; translational and implementation sciences in real-world clinical environments; regulatory and reimbursement considerations, and challenges in measuring outcomes. A cross-cutting theme was the need for careful attention to workflow. Our clinical setting, a safety-net health care system, presented some distinctive challenges. Patients often had multiple chronic illnesses and sometimes were taking more than one pharmacogenomics-relevant medication. Reaching patients for recruitment or follow-up was another challenge. Conclusions New, large-scale endeavors in health care are challenging. A description of the challenges that we encountered and the approaches that we adopted to address them may provide insights for those who implement and study innovations in other health care systems.
Neutrosophic masses & indeterminate models. Applications to information fusion

In this paper we introduce the indeterminate models in information fusion, which are due either to the existence of some indeterminate elements in the fusion space or to some indeterminate masses. The best approach for dealing with such models is the neutrosophic logic.
Do Oil Futures Prices Predict Stock Returns

Abstract This paper explores stock return predictability by exploiting the cross-section of oil futures prices. Motivated by the principal component analysis, we find the curvature factor of the oil futures curve predicts monthly stock returns: a 1% per month increase in the curvature factor predicts 0.4% per month decrease in stock market index return. This predictive pattern is prevailing in non-oil industry portfolios, but is absent for oil-related portfolios. The in- and out-of-sample predictive power of the curvature factor for non-oil stocks is robust and outperforms many other predictors, including oil spot prices. The predictive power of the curvature factor comes from its ability to forecast supply-side oil shocks, which only affect non-oil stocks and are hedged by oil-related stocks.
Dynamo-driven plasmoid formation from a current-sheet instability

Axisymmetric current-carrying plasmoids are formed in the presence of nonaxisymmetric fluctuations during nonlinear three-dimensional resistive MHD simulations in a global toroidal geometry. We utilize the helicity injection technique to form an initial poloidal flux in the presence of a toroidal guide field. As helicity is injected, two types of current sheets are formed from (1) the oppositely directed field lines in the injector region (primary reconnecting current sheet), and (2) the poloidal flux compression near the plasma edge (edge current sheet). We first find that nonaxisymmetric fluctuations arising from the current-sheet instability isolated near the plasma edge have tearing parity but can nevertheless grow fast (on the poloidal Alfven time scale). These modes saturate by breaking up the current sheet. Second, for the first time, a dynamo poloidal flux amplification is observed at the reconnection site (in the region of the oppositely directed magnetic field). This fluctuation-induced flux amp...
Can Time-Varying Risk of Rare Disasters Explain Aggregate Stock Market Volatility?

Why is the equity premium so high, and why are stocks so volatile? Why are stock returns in excess of government bill rates predictable? This paper proposes an answer to these questions based on a time-varying probability of a consumption disaster. In the model, aggregate consumption follows a normal distribution with low volatility most of the time, but with some probability of a consumption realization far out in the left tail. The possibility of this poor outcome substantially increases the equity premium, while time-variation in the probability of this outcome drives high stock market volatility and excess return predictability. THE MAGNITUDE OF THE expected excess return on stocks relative to bonds (the equity premium) constitutes one of the major puzzles in financial economics. As Mehra and Prescott (1985 )s how, the fl uctuations observed in the consumption growth rate over U.S. history predict an equity premium that is far too small, assuming reasonable levels of risk aversion. 1 One proposed explanation is that the return on equities is high to compensate investors for the risk of a rare disaster (Rietz (1988)). An open question has therefore been whether the risk is sufficiently high, and the rare disaster sufficiently severe, to quantitatively explain the equity premium. Recently, however, Barro (2006) shows that it is possible to explain the equity premium using such a model when the probability of a rare disaster is calibrated to international data on large economic declines. WhilethemodelsofRietz(1988)andBarro(2006)advanceourunderstanding
Controlling False Discoveries During Interactive Data Exploration

Recent tools for interactive data exploration significantly increase the chance that users make false discoveries. They allow users to (visually) examine many hypotheses and make inference with simple interactions, and thus incur the issue commonly known in statistics as the "multiple hypothesis testing error." In this work, we propose a solution to integrate the control of multiple hypothesis testing into interactive data exploration systems. A key insight is that existing methods for controlling the false discovery rate (such as FDR) are not directly applicable to interactive data exploration. We therefore discuss a set of new control procedures that are better suited for this task and integrate them in our system, QUDE. Via extensive experiments on both real-world and synthetic data sets we demonstrate how QUDE can help experts and novice users alike to efficiently control false discoveries.
A Functional Genomic Meta-Analysis of Clinical Trials in Systemic Sclerosis: Toward Precision Medicine and Combination Therapy.

Systemic sclerosis is an orphan, systemic autoimmune disease with no FDA-approved treatments. Its heterogeneity and rarity often result in underpowered clinical trials making the analysis and interpretation of associated molecular data challenging. We performed a meta-analysis of gene expression data from skin biopsies of patients with systemic sclerosis treated with five therapies: mycophenolate mofetil, rituximab, abatacept, nilotinib, and fresolimumab. A common clinical improvement criterion of −20% or −5 modified Rodnan skin score was applied to each study. We applied a machine learning approach that captured features beyond differential expression and was better at identifying targets of therapies than the differential expression alone. Regardless of treatment mechanism, abrogation of inflammatory pathways accompanied clinical improvement in multiple studies suggesting that high expression of immune-related genes indicates active and targetable disease. Our framework allowed us to compare different trials and ask if patients who failed one therapy would likely improve on a different therapy, based on changes in gene expression. Genes with high expression at baseline in fresolimumab nonimprovers were downregulated in mycophenolate mofetil improvers, suggesting that immunomodulatory or combination therapy may have benefitted these patients. This approach can be broadly applied to increase tissue specificity and sensitivity of differential expression results.
On the Communication Complexity of Approximate Fixed Points

We study the two-party communication complexity of finding an approximate Brouwer fixed point of a composition of two Lipschitz functions g ○ f: [0,1]n → [0,1]n, where Alice holds f and Bob holds g. We prove an exponential (in n) lower bound on the deterministic communication complexity of this problem. Our technical approach is to adapt the Raz-McKenzie simulation theorem (FOCS 1999) into geometric settings, thereby "smoothly lifting" the deterministic query lower bound for finding an approximate fixed point (Hirsch, Papadimitriou and Vavasis, Complexity 1989) from the oracle model to the two-party model. Our results also suggest an approach to the well-known open problem of proving strong lower bounds on the communication complexity of computing approximate Nash equilibria. Specifically, we show that a slightly "smoother" version of our fixed-point computation lower bound (by an absolute constant factor) would imply that: ● The deterministic two-party communication complexity of finding an e = Ω(1/log2 N)-approximate Nash equilibrium in an N × N bimatrix game (where each player knows only his own payoff matrix) is at least Nγ for some constant γ > 0. (In contrast, the nondeterministic communication complexity of this problem is only O(log6 N)). ● The deterministic (Number-In-Hand) multiparty communication complexity of finding an e = Ω(1)-Nash equilibrium in a k-player constant-action game is at least 2Ω(k/log k) (while the nondeterministic communication complexity is only O(k)).
Subnational diversity in Sub-Saharan Africa: Insights from a new dataset

Abstract This paper presents a new dataset on subnational ethnolinguistic and religious diversity in Sub-Saharan Africa covering 36 countries and almost 400 first-level administrative units. We use population censuses and large-scale household surveys to compile detailed data on the ethnolinguistic composition of each region and match all reported ethnicities to Ethnologue, a comprehensive catalog of world languages. This matching allows us to standardize the notion of an ethnolinguistic group and account for relatedness between language pairs, a correlate of shared history and culture, when calculating diversity indices. Exploiting within-country variation provided by our new dataset, we find that local public goods provision, as reflected in metrics of education, health, and electricity access, is negatively related to ethnolinguistic diversity, but only if the underlying basic languages are first aggregated into larger families or if linguistic distances between groups are taken into consideration. In other words, only deep-rooted diversity, based on cleavages formed in the distant past, is strongly inversely associated with a range of regional development indicators. Furthermore, we show that subnational diversity has been remarkably persistent over the past two-three decades implying that population sorting in the short to medium run is unlikely to bias our main findings.
Graded Clifford Algebras and Graded Skew Clifford Algebras and Their Role in the Classification of Artin–Schelter Regular Algebras

This paper is a survey of work done on $$\mathbb {Z}$$ -graded Clifford algebras (GCAs) and $$\mathbb {Z}$$ -graded skew Clifford algebras (GSCAs) by Vancliff et al. (Commun Algebra 26(4): 1193–1208, 1998), Stephenson and Vancliff (J Algebra 312(1): 86–110, 2007), Cassidy and Vancliff (J Lond Math Soc 81:91–112, 2010), Nafari et al. (J Algebra 346(1): 152–164, 2011), Vancliff and Veerapen (Contemp Math 592: 241–250, 2013), (J Algebra 420:54–64, 2014). In particular, we discuss the hypotheses necessary for these algebras to be Artin Schelter-regular (Adv Math 66:171–216, 1987), (The Grothendieck Festschrift. Birkhauser, Boston, 1990) and show how certain ‘points’ called, point modules, can be associated to them. We may view an AS-regular algebra as a noncommutative analog of the polynomial ring. We begin our survey with a fundamental result in Vancliff et al. (Commun Algebra 26(4): 1193–1208, 1998) that is essential to subsequent results discussed here: the connection between point modules and rank-two quadrics. Using, in part, this connection the authors in Stephenson and Vancliff (J Algebra 312(1): 86–110, 2007) provide a method to construct GCAs with finitely many distinct isomorphism classes of point modules. In Cassidy and Vancliff (J Lond Math Soc 81:91–112, 2010), Cassidy and Vancliff introduce a quantized analog of a GCA, called a graded skew Clifford algebra and Nafari et al. (J Algebra 346(1): 152–164, 2011) show that most Artin Schelter-regular algebras of global dimension three are either twists of graded skew Clifford algebras of global dimension three or Ore extensions of graded Clifford algebras of global dimension two. Vancliff and Veerapen (Contemp Math 592: 241–250, 2013), (J Algebra 420:54–64, 2014) go a step further and generalize the result of Vancliff et al. (Commun Algebra 26(4): 1193–1208, 1998), between point modules and rank-two quadrics, by showing that point modules over GSCAs are determined by (noncommutative) quadrics of $$\mu $$ -rank at most two.
CHEMSODE: a stiff ODE solver for the equations of chemical kinetics

Abstract The ODEs describing a chemical kinetics system can be very stiff and are the most computationally costly part of most reactive flow simulations. Research areas ranging from combustion to climate modeling are often limited by their ability to solve these chemical ODE systems both accurately and efficiently. These problems are commonly treated with an implicit numerical method due to the stiffness that is usually present. The implicit solution technique introduces a large amount of computational overhead necessary to solve the nonlinear algebraic system derived from the implicit time-stepping method. In this paper, a code is presented that avoids much of the usual overhead by preconditioning the implicit method with an iterative technique. This results in a class of time-stepping method that is explicit and very stable for chemical kinetics problems.
Predicting Ground-Level Scene Layout from Aerial Imagery

We introduce a novel strategy for learning to extract semantically meaningful features from aerial imagery. Instead of manually labeling the aerial imagery, we propose to predict (noisy) semantic features automatically extracted from co-located ground imagery. Our network architecture takes an aerial image as input, extracts features using a convolutional neural network, and then applies an adaptive transformation to map these features into the ground-level perspective. We use an end-to-end learning approach to minimize the difference between the semantic segmentation extracted directly from the ground image and the semantic segmentation predicted solely based on the aerial image. We show that a model learned using this strategy, with no additional training, is already capable of rough semantic labeling of aerial imagery. Furthermore, we demonstrate that by finetuning this model we can achieve more accurate semantic segmentation than two baseline initialization strategies. We use our network to address the task of estimating the geolocation and geo-orientation of a ground image. Finally, we show how features extracted from an aerial image can be used to hallucinate a plausible ground-level panorama.
The phase problem of x-ray crystallography

The intensities of a sufficient number of X-ray diffraction maxima determine the structure of a crystal, that is, the positions of the atoms in the unit cell of the crystal. The available intensities usually exceed the number of parameters needed to describe the structure. From these intensities a set of numbers \EH / can be derived, one corresponding to each intensity. However, the elucidation of the crystal structure also requires a knowledge of the complex numbers En = \EH | ℒH). the normalized structure factors, of which only the magnitudes \EH\ can be determined from experiment. Thus, a “phase” ℒH, unobtainable from the diffraction experiment, must be assigned to each |JEH /< and the problem of determining the phases when only the magnitudes \EH\ are known is called the “phase problem”. Owing to the known atomicity of crystal structures and the redundancy of observed magnitudes \EH |, the phase problem is solvable in principle.
Multiple instance hybrid estimator for learning target signatures

Signature-based detectors for hyperspectral target detection rely on knowing the specific target signature in advance. However, target signatures are often difficult or impossible to obtain. Furthermore, common methods for obtaining target signatures, such as from laboratory measurements or manual selection from an image scene, usually do not capture the discriminative features of target class. In this paper, an approach for estimating a discriminative target signature from imprecise labels is presented. The proposed approach maximizes the response of the hybrid sub-pixel detector within a multiple instance learning framework and estimates a set of discriminative target signatures. After learning target signatures, any signature based detector can then be applied on test data. Both simulated and real hyperspectral target detection experiments are shown to illustrate the effectiveness of the method.
Propensity score matching and subclassification in observational studies with multi-level treatments

In this article, we develop new methods for estimating average treatment effects in observational studies, in settings with more than two treatment levels, assuming unconfoundedness given pretreatment variables. We emphasize propensity score subclassification and matching methods which have been among the most popular methods in the binary treatment literature. Whereas the literature has suggested that these particular propensity-based methods do not naturally extend to the multi-level treatment case, we show, using the concept of weak unconfoundedness and the notion of the generalized propensity score, that adjusting for a scalar function of the pretreatment variables removes all biases associated with observed pretreatment variables. We apply the proposed methods to an analysis of the effect of treatments for fibromyalgia. We also carry out a simulation study to assess the finite sample performance of the methods relative to previously proposed methods.