cssi/SciSciGPT-SciSciNet huggingface dataset:
Are you really looking at me? A Feature-Extraction Framework for Estimating Interpersonal Eye Gaze from Conventional Video

Despite a revolution in the pervasiveness of video cameras in our daily lives, one of the most meaningful forms of nonverbal affective communication, interpersonal eye gaze, i.e. eye gaze relative to a conversation partner, is not available from common video. We introduce the Interpersonal-Calibrating Eye-gaze Encoder (ICE), which automatically extracts interpersonal gaze from video recordings without specialized hardware and without prior knowledge of participant locations. Leveraging the intuition that individuals spend a large portion of a conversation looking at each other enables the ICE dynamic clustering algorithm to extract interpersonal gaze. We validate ICE in both video chat using an objective metric with an infrared gaze tracker (F1=0.846, N=8), as well as in face-to-face communication with expert-rated evaluations of eye contact (r= 0.37, N-170). We then use ICE to analyze behavior in two different, yet important affective communication domains: interrogation-based deception detection, and communication skill assessment in speed dating. We find that honest witnesses break interpersonal gaze contact and look down more often than deceptive witnesses when answering questions (p=0.004, d=0.79). In predicting expert communication skill ratings in speed dating videos, we demonstrate that interpersonal gaze alone has more predictive power than facial expressions.
Seeing Is Believing: Experimental Spin States from Machine Learning Model Structure Predictions.

Determination of ground-state spins of open-shell transition metal complexes is critical to understanding catalytic and materials properties but also challenging with approximate electronic structu...
Quantum Monte Carlo calculations of light nuclei

Quantum Monte Carlo calculations using realistic two- and three-nucleon interactions are presented for nuclei with up to ten nucleons. Our Green's function Monte Carlo calculations are accurate to ∼1-2% for the binding energy. We have constructed Hamiltonians using the Argonne v18 NN interaction and reasonable three-nucleon interactions that reproduce the energies of these nuclear states with only ∼500 keV rms error. Other predictions, such as form factors, decay rates, and spectroscopic factors also agree well with data. Some of these results are presented to show that ab initio calculations of light nuclei are now well in hand.
Effects of advanced age upon astrocyte-specific responses to acute traumatic brain injury in mice

Older-age individuals are at the highest risk for disability from a traumatic brain injury (TBI). Astrocytes are the most numerous glia in the brain, necessary for brain function, yet there is little known about unique responses of astrocytes in the aged-brain following TBI. Our approach examined astrocytes in young adult, 4-month-old, versus aged, 18-month-old mice, at 1, 3, and 7 days post-TBI. We selected these time points to span the critical period in the transition from acute injury to presumably irreversible tissue damage and disability. Two approaches were used to define the astrocyte contribution to TBI by age interaction: (1) tissue histology and morphological phenotyping, and (2) transcriptomics on enriched astrocytes from the injured brain. Aging was found to have a profound effect on the TBI-induced loss of astrocyte function needed for maintaining water transport and edema—namely, aquaporin-4. The aged brain also demonstrated a progressive exacerbation of astrogliosis as a function of time after injury. Moreover, clasmatodendrosis, an underrecognized astrogliopathy, was found to be significantly increased in the aged brain, but not in the young brain. As a function of TBI, we observed a transitory refraction in the number of these astrocytes, which rebounded by 7 days post-injury in the aged brain. Transcriptomic data demonstrated disproportionate changes in genes attributed to reactive astrocytes, inflammatory response, complement pathway, and synaptic support in aged mice following TBI compared to young mice. Additionally, our data highlight that TBI did not evoke a clear alignment with the previously defined “A1/A2” dichotomy of reactive astrogliosis. Overall, our findings point toward a progressive phenotype of aged astrocytes following TBI that we hypothesize to be maladaptive, shedding new insights into potentially modifiable astrocyte-specific mechanisms that may underlie increased fragility of the aged brain to trauma.
Stabilization approaches for the hyperelastic immersed boundary method for problems of large-deformation incompressible elasticity.

Abstract The immersed boundary method is a mathematical framework for modeling fluid–structure interaction. This formulation describes the momentum, viscosity, and incompressibility of the fluid–structure system in Eulerian form, and it uses Lagrangian coordinates to describe the structural deformations, stresses, and resultant forces. Integral transforms with Dirac delta function kernels connect the Eulerian and Lagrangian frames. The fluid and the structure are both typically treated as incompressible materials. The discretization scheme can readily enforce incompressibility exactly for the Eulerian velocity field. Because of the regularization of the Dirac delta function kernel, however, the Lagrangian velocity field of the solid generally does not retain this property. To obtain an immersed method for incompressible hyperelastic structures that is robust under large structural deformations, we introduce a volumetric energy in the solid region that stabilizes the formulation and improves the accuracy of the numerical scheme. This formulation augments the discrete Eulerian Lagrange multiplier for the incompressibility constraint, thereby improving the original method’s accuracy. This volumetric energy is incorporated by decomposing the strain energy into isochoric and dilatational components, as in standard solid mechanics formulations of nearly incompressible elasticity. We study the performance of the stabilized method using several quasi-static solid mechanics benchmarks, a dynamic fluid–structure interaction benchmark, and a detailed three-dimensional model of esophageal transport. The accuracy achieved by the stabilized immersed formulation is empirically demonstrated to be comparable to that of a stabilized finite element method for incompressible elasticity using similar numbers of structural degrees of freedom.
OXIDE-ION ELECTROLYTES

▪ Abstract The performance of the oxide-ion electrolyte of a solid oxide fuel cell (SOFC) is critical to the development of an intermediate-temperature system. Although yttria-stabilized zirconia is the electrolyte used in SOFCs under commercial development, other candidate materials are now available, and there remains a strong motivation to search for new, improved oxide-ion electrolytes. The leading contenders are discussed not only with respect to their oxide-ion conductivity, but also with respect to mechanical and chemical compatibility with the electrodes and the working environment at each electrode.
Endogenous epistemic factionalization

Why do people who disagree about one subject tend to disagree about other subjects as well? In this paper, we introduce a model to explore this phenomenon of ‘epistemic factionization’. Agents attempt to discover the truth about multiple propositions by testing the world and sharing evidence gathered. But agents tend to mistrust evidence shared by those who do not hold similar beliefs. This mistrust leads to the endogenous emergence of factions of agents with multiple, highly correlated, polarized beliefs.
Chapter 9 – Respiratory Systems

There are many striking similarities between the physiological systems of vertebrates and those of insects, but one conspicuous difference is in the way that oxygen is brought to the cells. This difference was unusual enough for Aristotle, in 350 BCE, to characterize insects as terrestrial animals that had no requirement to inhale. It was Malpighi, in 1669, who first identified the series of branching tubes, the tracheae (singular: trachea), that bring oxygen directly to tissues, a departure from the system in vertebrates, where air is regularly and often visibly drawn into the body to oxygenate body fluids that are then circulated to all cells.
Identification of multivariable high-performance turbofan engine dynamics from closed-loop data

A typical engine control design cycle consists of developing a dynamic engine simulation from steady-state component performance data, designing a control based upon this simulation, and then testing and modifying the control in an engine test cell to meet performance requirements. This design cycle was successful for state-of-the-art engines. However, for more advanced multivariable engines that exhibit strong variable interactions, this procedure will result in substantial trial and error modification of the control during the testing phase. One method to automate the design process and reduce control modification testing and development cost would be to identify accurate dynamic models directly from the closed-loop test data. These identified models would then be used in conjunction with a synthesis procedure to systematically refine the control. Recent advances in closed-loop identifiability present a methodology for this direct identification of engine model dynamics from closed-loop test data. The application of an identification method to simulated and actual closed-loop F100 engine data is described. This study was undertaken to determine if useful dynamic engine models could be identified directly from closed-loop engine test data.
A Seasat-A Synthetic Aperture Imaging Radar System

The Seasat-A Synthetic Aperture Imaging Radar System is the first radar system of its kind designed for the study of ocean wave patterns from orbit. The basic requirement of this system is to generate continuous radar imagery with a 100-km swath with 25 m resolution from an orbital altitude of 800 km. These requirements impose unique system design problems and their solutions will be stated. The end to end data system will be described including interactions of the spacecraft, antenna, sensor, telemetry link, and data processor. The synthetic aperture radar system generates a large quantity of data (110 megabits per second) requiring the use of a dedicated data link. The data link selected for use with the synthetic aperture radar is an analog link with stable local oscillator encoding. The problems associated in telemetering the radar information with sufficient fidelity to synthesize an image on the ground will be described as well as the selected solutions to the problems.
Chapter 11 – Database Management Systems, Management Information Systems, Decision Support Systems

In this chapter we consider computer applications systems, particularly those used in businesses. We discuss several major types of applications systems including database management systems (DBMS), management information systems (MIS), and decision support systems (DSS). Each of these plays an important part in managing the huge amounts of information that businesses must process quickly and accurately. We present many case studies and point out important trends that are shaping the applications systems of the future.
Firm Relocation Threats and Copy Cat Costs

To retain firms, states are forgiving billions of dollars in tax liabilities. Some firms move even after a relief package is offered; other firms obtain tax concessions by bluffing. When firms threaten to relocate unless their current tax burden is lightened, what should a local government do? If it offers relief, at best it retains the firm, but it also encourages other firms ("copy cats") to demand similar treatment. At worst, it loses the firm and has to deal with the additional threats. Tax incentive packages can cost much more than foregone revenues related to the single threatening firm. We solve a local government's constrained optimization problem to identify its optimal response in a game theoretic framework with asymmetric information. Industrial recruitment is modeled as a sealed-bid process in which the government does not know what alternative tax package(s) may be offered to the firm. We show that the probability of a relief offer being the optimal response is positively related to the rate ...
Constrained percolation, Ising model, and XOR Ising model on planar lattices

We study constrained percolation models on planar lattices including the $[m,4,n,4]$ lattice and the square tilings of the hyperbolic plane, satisfying certain local constraints on faces of degree 4, and investigate the existence of infinite clusters. The constrained percolation models on these lattices are closely related to Ising models and XOR Ising models on regular tilings of the Euclidean plane or the hyperbolic plane. In particular, we obtain a complete picture of the number of infinite "$+$" and "$-$" clusters of the ferromagnetic Ising model with the free boundary condition on a vertex-transitive triangular tiling of the hyperbolic plane with all the possible values of coupling constants. Our results show that for the Ising model on a vertex-transitive triangular tiling of the hyperbolic plane, it is possible that its random cluster representation has no infinite open clusters, while the Ising model has infinitely many infinite "$+$"-clusters and infinitely many infinite "$-$"-clusters. We also study different behaviors the infinite "$+$" and "$-$" clusters of XOR Ising models on regular tilings of the Euclidean plane and the hyperbolic plane for different coupling constants. A by-product we prove is the result that the critical random cluster model with $q\geq 1$ and the wired boundary condition on a quasi-transitive, non-amenable, unimodular graph almost surely has no infinite open clusters.
Real Exchange Rate and International Reserves in an Era of Growing Financial and Trade Integration

Abstract This paper evaluates the impact of international reserves, terms-of-trade shocks, and capital flows on the real exchange rate (REER). We observe that international reserves cushion the impact of terms-of-trade shocks on REER, and that this effect is important for developing but not for industrial countries. This buffer effect is especially significant for Asian countries, and for countries exporting natural resources. Financial depth reduces the buffer role of international reserves in developing countries. Developing countries' REERs seem to be more sensitive to changes in reserve assets; whereas industrial countries display a significant relationship between hot money and REER.
Interviewing in two‐sided matching markets

We introduce the interview assignment problem, which generalizes the oneto-one matching model of Gale and Shapley (1962) by including a stage of costly information acquisition. Agents do not know their preferences over potential partners unless they choose to conduct costly interviews. Although there may exist many equilibria in which all agents are assigned the same number of interviews, we show the e‐ciency of the resultant match can vary signiflcantly depending on the degree of overlap { the number of common interview partners among agents { exhibited by the interview assignment. Among all such equilibria, the one with the highest degree of overlap yields the highest probability of being matched for any agent. Our analysis is used to motivate new and explain existing coordinating mechanisms prevalent in markets with interviewing.
Intervention Adherence and Self-Efficacy as Predictors of Child Outcomes in School Nurse–Delivered Interventions for Anxiety:

This study examined the association between two implementation factors, nurse-reported intervention adherence and self-efficacy, and children's outcomes in school nurse-delivered anxiety interventions. Data were collected in a pilot randomized controlled effectiveness trial with 54 children and 21 school nurses. Nurses implemented either a cognitive behavioral or relaxation-skills-only intervention. Nurse questionnaires assessed implementation factors. Independent evaluators assessed changes in children's anxiety symptoms at postintervention and at 3-month follow-up using clinical improvement and global functioning scales. Regression analyses indicated that greater intervention adherence was associated with greater anxiety symptom improvement at follow-up. Nurse self-efficacy interacted with intervention group, such that nurses with higher self-efficacy who implemented the cognitive behavioral intervention tended to have children show improvement and higher postintervention functioning. The impact of implementation factors on children's outcomes may differ depending on intervention type. Self-efficacy may be important for nurses using relatively complex interventions. Intervention adherence should be supported through training and consultation.
The free group on n generators modulo n + u random relations as n goes to infinity

We show that, as n goes to infinity, the free group on n generators, modulo n+u random relations, converges to a random group that we give explicitly. This random group is a non-abelian version of the random abelian groups that feature in the Cohen-Lenstra heuristics. For each n, these random groups belong to the few relator model in the Gromov model of random groups.
Synthesis and Diels-Alder Reactivity of 4-Fluoro-4-Methyl-4H-Pyrazoles.

4H-Pyrazoles are emerging scaffolds for “click” chemistry. Late-stage fluorination with Selectfluor® is found to provide a reliable route to 4-fluoro-4-methyl-4H-pyrazoles. 4-Fluoro-4-methyl-3,5-diphenyl-4H-pyrazole (MFP) manifested 7-fold lower Diels–Alder reactivity than did 4,4-difluoro-3,5-diphenyl-4H-pyrazole (DFP), but higher stability in the presence of biological nucleophiles. Calculations indicate that a large decrease in the hyperconjugative antiaromaticity in MFP relative to DFP does not lead to a large loss in Diels–Alder reactivity because the ground-state structure of MFP avoids hyperconjugative antiaromaticity by distorting into an envelope-like conformation like that in the Diels–Alder transition state. This predistortion enhances the reactivity of MFP and offsets the decrease in reactivity from the diminished hyperconjugative antiaromaticity.
Differential Privacy for Stackelberg Games

This paper introduces a differentially private (DP) mechanism to protect the information exchanged during the coordination of sequential and interdependent markets. This coordination represents a classic Stackelberg game and relies on the exchange of sensitive information between the system agents. The paper is motivated by the observation that the perturbation introduced by traditional DP mechanisms fundamentally changes the underlying optimization problem and even leads to unsatisfiable instances. To remedy such limitation, the paper introduces the Privacy-Preserving Stackelberg Mechanism (PPSM), a framework that enforces the notions of feasibility and fidelity of the privacy-preserving information to the original problem objective. PPSM complies with the notion of differential privacy and ensures that the outcomes of the privacy-preserving coordination mechanism are close-to-optimality for each agent. Experimental results on several gas and electricity market benchmarks based on a real case study demonstrate the effectiveness of the approach.
Loss of prdm1a accelerates melanoma onset and progression

Melanoma is an aggressive, deadly skin cancer derived from melanocytes, a neural crest cell derivative. Melanoma cells mirror the developmental program of neural crest cells in that they exhibit the same gene expression patterns and utilize similar cellular mechanisms, including increased cell proliferation, epithelial-mesenchymal transition, and migration. Here we studied the role of neural crest regulator PRDM1 in melanoma onset and progression. In development, Prdm1a functions to promote neural crest progenitor fate, and in melanoma, we found that PRDM1 has reduced copy number and is recurrently deleted in both zebrafish and humans. When examining expression of neural crest and melanocyte development genes, we show that sox10 progenitor expression is high in prdm1a-/- mutants, while more differentiated melanocyte markers are reduced, suggesting that normally Prdm1a is required for differentiation. Data mining of human melanoma datasets indicates that high PRDM1 expression in human melanoma is correlated with better patient survival and decreased PRDM1 expression is common in metastatic tumors. When one copy of prdm1a is lost in the zebrafish melanoma model Tg(mitfa:BRAFV600E );p53-/- ;prdm1a+/- , melanoma onset occurs more quickly, and the tumors that form have a larger area with increased expression of sox10. These data demonstrate a novel role for PRDM1 as a tumor suppressor in melanoma.
Structures of Human Antibodies Bound to SARS-CoV-2 Spike Reveal Common Epitopes and Recurrent Features of Antibodies.

Neutralizing antibody responses to coronaviruses mainly target the receptor-binding domain (RBD) of the trimeric spike. Here, we characterized polyclonal immunoglobulin Gs (IgGs) and Fabs from COVID-19 convalescent individuals for recognition of coronavirus spikes. Plasma IgGs differed in their focus on RBD epitopes, recognition of alpha- and beta-coronaviruses, and contributions of avidity to increased binding/neutralization of IgGs over Fabs. Using electron microscopy, we examined specificities of polyclonal plasma Fabs, revealing recognition of both S1A and RBD epitopes on SARS-CoV-2 spike. Moreover, a 3.4 A cryo-electron microscopy (cryo-EM) structure of a neutralizing monoclonal Fab-spike complex revealed an epitope that blocks ACE2 receptor binding. Modeling based on these structures suggested different potentials for inter-spike crosslinking by IgGs on viruses, and characterized IgGs would not be affected by identified SARS-CoV-2 spike mutations. Overall, our studies structurally define a recurrent anti-SARS-CoV-2 antibody class derived from VH3-53/VH3-66 and similarity to a SARS-CoV VH3-30 antibody, providing criteria for evaluating vaccine-elicited antibodies.
Effect of concomitant deep venous reflux on truncal endovenous ablation outcomes in the Vascular Quality Initiative

Abstract Objective Few studies have investigated outcomes after truncal endovenous ablation in patients with combined deep and superficial reflux and no studies have evaluated patient-reported outcomes. Methods We investigated the short- and long-term clinical and patient-reported outcomes among patients with and without deep venous reflux undergoing truncal endovenous ablation from 2015 to 2019 in the Vascular Quality Initiative. Preprocedural and postprocedural comparisons were performed using the t-test, χ2, or their nonparametric counterpart when appropriate. Multivariable logistic regression models were used to assess for confounding. Results A total of 4881 patients were included, of which 2254 (46.2%) had combined deep and superficial reflux. The median follow-up was 336.5 days. Patients with deep reflux were less likely to be female (65.9% vs 69.9%; P = .003), more likely to be Caucasian (90.2% vs 86.5%; P = .003) and had no difference in BMI (30.6 ± 7.5 vs 30.6 ± 7.2; P = .904). Additionally, no difference was seen in rates of prior varicose vein treatments, number of pregnancies, or history of deep venous thrombosis; however, patients without deep reflux were more likely to be on anticoagulation at the time of the procedure (10.9% vs 8.1%; P Conclusions No significant difference is seen in total symptom improvement when patients undergo truncal endovenous ablation with concomitant deep venous reflux, although a greater improvement was seen in VCSS score in these patients. Patients with deep venous reflux had a significantly increased rate of complications, independent of confounding variables, and should be counseled appropriately before the decision for treatment.
Self-reported COVID-19 symptoms on Twitter: an analysis and a research resource.

OBJECTIVE: To mine Twitter and quantitatively analyze COVID-19 symptoms self-reported by users, compare symptom distributions across studies, and create a symptom lexicon for future research. MATERIALS AND METHODS: We retrieved tweets using COVID-19-related keywords, and performed semiautomatic filtering to curate self-reports of positive-tested users. We extracted COVID-19-related symptoms mentioned by the users, mapped them to standard concept IDs in the Unified Medical Language System, and compared the distributions to those reported in early studies from clinical settings. RESULTS: We identified 203 positive-tested users who reported 1002 symptoms using 668 unique expressions. The most frequently-reported symptoms were fever/pyrexia (66.1%), cough (57.9%), body ache/pain (42.7%), fatigue (42.1%), headache (37.4%), and dyspnea (36.3%) amongst users who reported at least 1 symptom. Mild symptoms, such as anosmia (28.7%) and ageusia (28.1%), were frequently reported on Twitter, but not in clinical studies. CONCLUSION: The spectrum of COVID-19 symptoms identified from Twitter may complement those identified in clinical settings.
Cargo and cell‐specific differences in extracellular vesicle populations identified by multiplexed immunofluorescent analysis

Extracellular vesicles (EVs) have been implicated in a wide variety of biological activities, have been implicated in the pathogenesis of numerous diseases, and have been proposed to serve as potential biomarkers of disease in human patients and animal models. However, characterization of EV populations is often performed using methods that do not account for the heterogeneity of EV populations and require comparatively large sample sizes to facilitate analysis. Here, we describe an imaging-based method that allows for the multiplexed characterization of EV populations at the single EV level following centrifugation of EV populations directly onto cover slips, allowing comprehensive analysis of EV populations with relatively small samples. We observe that canonical EV markers are present on subsets of EVs which differ substantially in a producer cell and cargo specific fashion, including differences in EVs containing different HIV-1 proteins previously reported to be incorporated into pathogenic EVs. We also describe a lectin binding assay to interrogate EVs based on their glycan content, which we observe to change in response to pharmacological modulation of secretory autophagy pathways. These studies collectively reveal that a multiplexed analysis of EV populations using fluorescent microscopy can reveal differences in specific EV populations that may be used to understand the biogenesis of specific EV populations and/or to interrogate small subsets of EVs of interest within larger EV populations in biological samples.
Scheduling Low Latency Traffic for Wireless Control Systems in 5G Networks

We consider the problem of allocating 5G radio resources over wireless communication links to control a series of independent low-latency wireless control systems common in industrial settings. Each control system sends state information to the base station to compute control signals under tight latency requirements. Such latency requirements can be met by restricting the uplink traffic to a single subframe in each 5G frame, thus ensuring a millisecond latency bound while leaving the remaining subframes available for scheduling overhead and coexisting broadband traffic. A linear assignment problem can be formulated to minimize the expected number of packet drops, but this alone is not sufficient to achieve good performance. We propose an optimal scheduling with respect to a control operation cost that allocates resources based on current control system needs. The resulting control-aware scheduling method is tested in simulation experiments that show drastically improved performance in 5G settings relative to control-agnostic scheduling under the proposed time-sliced frame structure.
Lunar Terrain Relative Navigation Using a Convolutional Neural Network for Visual Crater Detection

Terrain relative navigation can improve the precision of a spacecraft's position estimate by detecting global features that act as supplementary measurements to correct for drift in the inertial navigation system. This paper presents a system that uses a convolutional neural network (CNN) and image processing methods to track the location of a simulated spacecraft with an extended Kalman filter (EKF). The CNN, called LunaNet, visually detects craters in the simulated camera frame and those detections are matched to known lunar craters in the region of the current estimated spacecraft position. These matched craters are treated as features that are tracked using the EKF. LunaNet enables more reliable position tracking over a simulated trajectory due to its greater robustness to changes in image brightness and more repeatable crater detections from frame to frame throughout a trajectory. LunaNet combined with an EKF produces a decrease of 60% in the average final position estimation error and a decrease of 25% in average final velocity estimation error compared to an EKF using an image processing-based crater detection method when tested on trajectories using images of standard brightness.
Geometric modeling and regularization of algebraic problems

Discontinuity with respect to data perturbations is common in algebraic computation where solutions are often highly sensitive. Such problems can be modeled as solving systems of equations at given data parameters. By appending auxiliary equations, the models can be formulated to satisfy four easily verifiable conditions so that the data form complex analytic manifolds on which the solutions maintain their structures and the Lipschitz continuity. When such a problem is given with empirical data, solving the system becomes a least squares problem whose solution uniquely exists and enjoys Lipschitz continuity as long as the data point is in a tubular neighborhood of the manifold. As a result, the singular problem is regularized as a well-posed computational problem.
Confidence and the Propagation of Demand Shocks

We revisit the question of why shifts in aggregate demand drive business cycles. Our theory combines intertemporal substitution in production with rational confusion (or bounded rationality) in consumption. The first element allows aggregate supply to respond to shifts in aggregate demand without nominal rigidity. The second introduces a “confidence multiplier,” namely a positive feedback loop between real economic activity, consumer expectations of permanent income, and investor expectations of returns. This mechanism amplifies the business-cycle fluctuations triggered by demand shocks (but not those triggered by supply shocks); it helps investment to comove with consumption; and it allows front-loaded fiscal stimuli to crowd in private spending.
A microbial perspective on balancing trade-offs in ecosystem functions in a constructed stormwater wetland

Abstract Green stormwater infrastructure, such as constructed wetlands (CWs), is a type of stormwater control measure that can decrease nutrient and pollutant loads from urban stormwater runoff. Wetland soil microorganisms provide nutrient and pollutant removal benefits which can also result in ecosystem disservices such as greenhouse gas (GHG) emissions and can inadvertently exacerbate climate change. Microbial respiration by facultative anaerobes in anoxic conditions is the primary pathway for nitrogen removal (benefit). Similar anoxic conditions that support denitrifying microorganisms can also support obligate anaerobes that produce methane (CH4) via methanogenesis (disservice). We examined nitrogen removal potential, GHG production, and microbial community structure within permanently flooded and shallow land or temporarily-flooded areas of a stormwater CW to identify zones for CW design optimization. Results indicate that permanently flooded zones compared to shallow land zones are greater sources of CH4 emissions (80.80 ± 118.31, 2.32 ± 9.33 mg CH4-C m−2 h−1, respectively) and emit more carbon to the atmosphere (7161.27 kg CO2, 93.20 kg CO2 equivalents, respectively). However, nitrogen removal potential rates were similar across both flooded and shallow land zones (24.45 ± 20.18, 20.29 ± 15.14 ng N2O-N hr−1 g−1 dry soil, respectively). At this particular CW, reduction of permanently flooded zones within the wetland could decrease GHG emissions (disservice) without limiting nitrogen removal (benefit) potential of the wetland. Holistic development and design of stormwater control measures, which account for microbial activity, provides the opportunity to maximize benefits (i.e., nutrient and pollutant removal) and reduce disservices (i.e., GHG emissions) of green stormwater infrastructure.
Polygenic scores for height in admixed populations

Polygenic risk scores (PRS) use the results of genome-wide association studies (GWAS) to predict quantitative phenotypes or disease risk at an individual level, and provide a potential route to the use of genetic data in personalized medical care. However, a major barrier to the use of PRS is that the majority of GWAS come from cohorts of European ancestry. The predictive power of PRS constructed from these studies is substantially lower in non-European ancestry cohorts, although the reasons for this are unclear. To address this question, we investigate the performance of PRS for height in cohorts with admixed African and European ancestry, allowing us to evaluate ancestry-related differences in PRS predictive accuracy while controlling for environment and cohort differences. We first show that the predictive accuracy of height PRS increases linearly with European ancestry and is partially explained by European ancestry segments of the admixed genomes. We show that recombination rate, differences in allele frequencies, and differences in marginal effect sizes across ancestries all contribute to the decrease in predictive power, but none of these effects explain the decrease on its own. Finally, we demonstrate that prediction for admixed individuals can be improved by using a linear combination of PRS that includes ancestry-specific effect sizes, although this approach is at present limited by the small size of non-European ancestry discovery cohorts.
Strategic management in local hospital markets: service duplication or service differentiation.

The purpose of this study is to assess the influences of market structure on hospitals’ strategic decision to duplicate or differentiate services and to assess the relationship of duplication and differentiation to hospital performance. This study is different from previous research because it examines how a hospital decides which services to be duplicated or differentiated in a dyadic relationship embedded in a complex competitive network. We use Linear Structural Equations (LISREL) to simultaneously estimate the relationships among market structure, duplicated and differentiated services, and performance. All non-federal, general acute hospitals in urban counties in the United States with more than one hospital are included in the sample (n = 1726). Forty-two high-tech services are selected for the study. Data are compiled from the American Hospital Association Annual Survey of Hospitals, Area Resource File, and CMS cost report files. State data from HealthLeaders-InterStudy for 2015 are also used. The findings provide support that hospitals duplicate and differentiate services relative to rivals in a local market. Size asymmetry between hospitals is related to both service duplication (negatively) and service differentiation (positively). With greater size asymmetry, a hospital utilizes its valuable resources for its own advantage to thwart competition from rivals by differentiating more high-tech services and reducing service duplication. Geographic distance is positively related to service duplication, with duplication increasing as distance between hospitals increases. Market competition is associated with lower service duplication. Both service differentiation and service duplication are associated with lower market share, higher costs, and lower profits. The findings underscore the role of market structure as a check and balance on the provision of high-tech services. Hospital management should consider cutting back some services that are oversupplied and/or unprofitable and analyze the supply and demand in the market to avoid overdoing both service duplication and service differentiation.
Placental microRNA expression associates with birthweight through control of adipokines: results from two independent cohorts.

MicroRNAs are non-coding RNAs that regulate gene expression post-transcriptionally. In the placenta, the master regulator of foetal growth and development, microRNAs shape the basic processes of tr...
CyPhyHouse: A programming, simulation, and deployment toolchain for heterogeneous distributed coordination

Programming languages, libraries, and development tools have transformed the application development processes for mobile computing and machine learning. This paper introduces CyPhyHouse—a toolchain that aims to provide similar programming, debugging, and deployment benefits for distributed mobile robotic applications. Users can develop hardware-agnostic, distributed applications using the high-level, event driven Koord programming language, without requiring expertise in controller design or distributed network protocols. The modular, platform-independent middleware of CyPhyHouse implements these functionalities using standard algorithms for path planning (RRT), control (MPC), mutual exclusion, etc. A high-fidelity, scalable, multi-threaded simulator for Koord applications is developed to simulate the same application code for dozens of heterogeneous agents. The same compiled code can also be deployed on heterogeneous mobile platforms. The effectiveness of CyPhyHouse in improving the design cycles is explicitly illustrated in a robotic testbed through development, simulation, and deployment of a distributed task allocation application on in-house ground and aerial vehicles.
Randomized Exploration for Non-Stationary Stochastic Linear Bandits.

We investigate two perturbation approaches to overcome conservatism that optimism based algorithms chronically suffer from in practice. The first approach replaces optimism with a simple randomization when using confidence sets. The second one adds random perturbations to its current estimate before maximizing the expected reward. For non-stationary linear bandits, where each action is associated with a $d$-dimensional feature and the unknown parameter is time-varying with total variation $B_T$, we propose two randomized algorithms, Discounted Randomized LinUCB (D-RandLinUCB) and Discounted Linear Thompson Sampling (D-LinTS) via the two perturbation approaches. We highlight the statistical optimality versus computational efficiency trade-off between them in that the former asymptotically achieves the optimal dynamic regret $\tilde{\mathcal{O}}(d ^{2/3}B_T^{1/3} T^{2/3})$, but the latter is oracle-efficient with an extra logarithmic factor in the number of arms compared to minimax-optimal dynamic regret. In a simulation study, both algorithms show outstanding performance in tackling conservatism issue that Discounted LinUCB struggles with.
PAC-Bayes control: learning policies that provably generalize to novel environments:

Our goal is to learn control policies for robots that provably generalize well to novel environments given a dataset of example environments. The key technical idea behind our approach is to levera...
The last guardian of the throne: the regional army in the late Qing dynasty

This paper investigates the organizational structure of the Xiang Army, one of the best-known regional armies in the late Qing dynasty. The army developed an organizational form to overcome problems that plagued the imperial army of the central government, namely, the poor recruitment and training of soldiers, the lack of incentives to fight in battles, and the coordination failure. This organizational structure, I argue, played a central role in the rise of the Xiang Army in the Qing dynasty.
Hyperbolic immersions of free groups

We prove that the mapping torus of a graph immersion has a word-hyperbolic fundamental group if and only if the corresponding endomorphism does not produce Baumslag-Solitar subgroups. Due to a result by Reynolds, this theorem applies to all injective endomorphisms of $F_2$ and nonsurjective fully irreducible endomorphisms of $F_n$. We also give a framework for extending the theorem to all injective endomorphisms of $F_n$.
Numerical Differentiation of Noisy Data: A Unifying Multi-Objective Optimization Framework

Computing derivatives of noisy measurement data is ubiquitous in the physical, engineering, and biological sciences, and it is often a critical step in developing dynamic models or designing control. Unfortunately, the mathematical formulation of numerical differentiation is typically ill-posed, and researchers often resort to an ad hoc process for choosing one of many computational methods and its parameters. In this work, we take a principled approach and propose a multi-objective optimization framework for choosing parameters that minimize a loss function to balance the faithfulness and smoothness of the derivative estimate. Our framework has three significant advantages. First, the task of selecting multiple parameters is reduced to choosing a single hyper-parameter. Second, where ground-truth data is unknown, we provide a heuristic for selecting this hyper-parameter based on the power spectrum and temporal resolution of the data. Third, the optimal value of the hyper-parameter is consistent across different differentiation methods, thus our approach unifies vastly different numerical differentiation methods and facilitates unbiased comparison of their results. Finally, we provide an extensive open-source Python library pynumdiff to facilitate easy application to diverse datasets ( https://github.com/florisvb/PyNumDiff ).
Metallic nature of the four-dimensional quantum hall edge

Abstract We study the density response of the four-dimensional quantum Hall fluid found by Zhang and Hu, which has been advanced as a model of emergent relativity. We calculate the density–density correlation function along the edge at half-filling, and show that it is similar to the three-dimensional free electron gas. This indicates that the edge of the four-dimensional quantum Hall fluid behaves like a metal.
MEAN EXIT TIME AND ESCAPE PROBABILITY FOR A TUMOR GROWTH SYSTEM UNDER NON-GAUSSIAN NOISE

Effects of non-Gaussian α-stable Levy noise on the Gompertz tumor growth model are quantified by considering the mean exit time and escape probability of the cancer cell density from inside a safe or benign domain. The mean exit time and escape probability problems are formulated in a differential-integral equation with a fractional Laplacian operator. Numerical simulations are conducted to evaluate how the mean exit time and escape probability vary or bifurcates when α changes. Some bifurcation phenomena are observed and their impacts are discussed.
Identification of simple reaction coordinates from complex dynamics

Reaction coordinates are widely used throughout chemical physics to model and understand complex chemical transformations. We introduce a definition of the natural reaction coordinate, suitable for condensed phase and biomolecular systems, as a maximally predictive one-dimensional projection. We then show that this criterion is uniquely satisfied by a dominant eigenfunction of an integral operator associated with the ensemble dynamics. We present a new sparse estimator for these eigenfunctions which can search through a large candidate pool of structural order parameters and build simple, interpretable approximations that employ only a small number of these order parameters. Example applications with a small molecule's rotational dynamics and simulations of protein conformational change and folding show that this approach can filter through statistical noise to identify simple reaction coordinates from complex dynamics.
Multipole hair of Schwarzschild-Tangherlini black holes

We study the field of an electric point charge that is slowly lowered into an n + 1 dimensional Schwarzschild-Tangherlini black hole. We find that if n > 3, then countably infinite nonzero multipole moments manifest to observers outside the event horizon as the charge falls in. This suggests the final state of the black hole is not characterized by a Reissner-Nordstrom-Tangherlini geometry. Instead, for odd n, the final state either possesses a degenerate horizon, undergoes a discontinuous topological transformation during the infall of the charge, or both. For even n, the final state is not guaranteed to be asymptotically flat.The author of the article agrees to the retraction of the article effective May 5, 2021.
Kloosterman sums and Fourier coefficients of Eisenstein series

We derive explicit formulas for some Kloosterman sums on $$\Gamma _0(N)$$ , and for the Fourier coefficients of Eisenstein series attached to arbitrary cusps, around a general Atkin–Lehner cusp.
The homotopy theory of cyclotomic spectra

We describe spectral model category structures on the categories of cyclotomic spectra and $p$-cyclotomic spectra (in orthogonal spectra) with triangulated homotopy categories. We show that the functors $TR$ and $TC$ are corepresentable in these categories. Specifically, the derived mapping spectrum out of the sphere spectrum in the category of cyclotomic spectra corepresents the finite completion of $TC$ and the derived mapping spectrum out of the sphere spectrum in the category of $p$-cyclotomic spectra corepresents the $p$-completion of $TC(-;p)$.
Decidable tag-based semantic subtyping for nominal types, tuples, and unions

Semantic subtyping enables simple, set-theoretical reasoning about types by interpreting a type as the set of its values. Previously, semantic subtyping has been studied primarily in the context of statically typed languages with structural typing. In this paper, we explore the applicability of semantic subtyping in the context of a dynamic language with nominal types. Instead of static type checking, dynamic languages rely on run-time checking of type tags associated with values, so we propose using the tags for semantic subtyping. We base our work on a fragment of the Julia language and present tag-based semantic subtyping for nominal types, tuples, and unions, where types are interpreted set-theoretically as sets of type tags. The proposed subtyping relation is shown to be decidable, and a corresponding analytic definition is provided. The implications of using semantic subtyping for multiple dispatch are also discussed.
Entanglement rates for Rényi, Tsallis, and other entropies

We provide an upper bound on the maximal entropy rate at which the entropy of the expected density operator of a given ensemble of two states changes under nonlocal unitary evolution. A large class of entropy measures in considered, which includes Renyi and Tsallis entropies. The result is derived from a general bound on the trace-norm of a commutator, which can be expected to find other implementations. We apply this result to bound the maximal rate at which quantum dynamics can generate entanglement in a bipartite closed system with Renyi and Tsallis entanglement entropies taken as measures of entanglement in the system.We provide an upper bound on the maximal entropy rate at which the entropy of the expected density operator of a given ensemble of two states changes under nonlocal unitary evolution. A large class of entropy measures in considered, which includes Renyi and Tsallis entropies. The result is derived from a general bound on the trace-norm of a commutator, which can be expected to find other implementations. We apply this result to bound the maximal rate at which quantum dynamics can generate entanglement in a bipartite closed system with Renyi and Tsallis entanglement entropies taken as measures of entanglement in the system.