cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
$P-V$ Criticality of Conformal Gravity Holography in Four Dimensions
Creators: name: Pradhan, Parthapratim
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: {We examine the critical behaviour i. e. $P-V$ criticality of conformal gravity~(CG) in an extended phase space in which the cosmological constant should be interpreted as a thermodynamic pressure and the corresponding conjugate quantity as a thermodynamic volume.} The main potential point of interest in CG is that there exists a {non-trivial} \emph{Rindler parameter ($a$)} in the {spacetime geometry. This geometric parameter has an important role to construct a model for gravity at large distances where the parameter "$a$" actually originates}. We also investigate the effect of the said parameter on the {black hole~(BH) \emph{thermodynamic} equation of state, critical constants, Reverse Isoperimetric Inequality,} {first law of thermodynamics, Hawking-Page phase transition and Gibbs free energy} for this BH. We speculate that due to the presence of the said parameter, there has been a deformation {in the shape} of {the} isotherms in the $P-V$ diagram in comparison with {the} charged-AdS~(anti de-Sitter) BH and {the} chargeless-AdS BH. Interestingly, we find {that} the \emph{critical ratio} for this BH is $ρ_{c} = \frac{P_{c} v_{c}}{T_{c}}= \frac{\sqrt{3}}{2}\left(3\sqrt{2}-2\sqrt{3}\right)$, which is greater than the charged AdS BH and Schwarzschild-AdS BH {i.e.} $ρ_{c}^{CG}:ρ_{c}^{Sch-AdS}:ρ_{c}^{RN-AdS} = 0.67:0.50:0.37$. The symbols are defined in the main work. Moreover, we observe that \emph{{the} critical ratio {has a constant value}} and {it is} independent of the {non-trivial} \emph{Rindler parameter ($a$)}. Finally, we derive {the} \emph{reduced equation of state} in terms of {the} \emph{reduced temperature}, {the} \emph{reduced volume} and {the} \emph{reduced pressure} respectively.
description: Accepted in MPLA, Modern Physics Letters A, 2018
Effective numerical treatment of sub-diffusion equation with non-smooth solution
Creators: name: Yang, Zongze
name: Wang, Jungang
name: Li, Yan
name: Nie, Yufeng
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: Primary 34A08, Secondary 26A33, 45D05, 65L12

description: In this paper we investigate a sub-diffusion equation for simulating the anomalous diffusion phenomenon in real physical environment. Based on an equivalent transformation of the original sub-diffusion equation followed by the use of a smooth operator, we devise a high-order numerical scheme by combining the Nystrom method in temporal direction with the compact finite difference method and the spectral method in spatial direction. The distinct advantage of this approach in comparison with most current methods is its high convergence rate even though the solution of the anomalous sub-diffusion equation usually has lower regularity on the starting point. The effectiveness and efficiency of our proposed method are verified by several numerical experiments.
description: 15 pages, 6 figures
Optimal conditions for high-fidelity dispersive readout of a qubit with a photon-number-resolving detector
Creators: name: Sokolov, Andrii
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We determine the optimal parameters for a simple and efficient scheme of dispersive readout of a qubit. Depending on the qubit state (ground or excited), the resonance of a cavity is shifted either to the red or to the blue side. Qubit state is inferred by detecting the photon number transmitted through the cavity. It turns out that this kind of detection provides better measurement fidelity than the detection of the presence or absence of photons only. We show that radiating the cavity on either of the frequencies it shifts to results in a suboptimal measurement. The optimal frequency of the probe photons is determined, as well as the optimal ratio of the shift to the resonator leakage. It is shown that to maximize the fidelity of a long-lasting measurement, it is sufficient to use the parameters optimizing the signal-to-noise ratio in the photon count. One can reach 99% fidelity for a single-shot measurement in various physical realizations of the scheme.
description: 12 pages, 6 figures
title: The Role of Perennialist Thought in the Development of Psychedelic Research in the United States
Creators: name: Springer, Nathan
Publisher: name: Georgia State University
Year: 1905

description:
From the 1960s to the present day, American research into the therapeutic effects of psychedelic drugs has focused on their ability to facilitate mystical experiences in test subjects. Mysticomimetic research has close ties to perennialist notions of religion that gained popularity over the course of the 20th century. Figures such as William James and Aldous Huxley promoted perennialist ideals within intellectual circles, particularly influencing psychological researchers. As research into psychedelics has gathered momentum from the 2000s onward, claims that mystical experience is key to the compounds palliative effects remain tied to perennialist thought, with current research picking up where studies in the 1960s left off. Perennialism can itself be considered a new religious movement that has developed in scientific and academic circles, the existence of which brings into relief the breakdown of notions of a dichotomist relationship between science and religion in the process.
SHIFTING THE GAZE OF AFRICAN AMERICAN INFANT FEEDING TO A PSYCHOLOGICAL, CULTURAL AND SOCIO-HISTORICAL LENS
Creators: name: DeVane-Johnson, Stephanie
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Despite efforts to address the disproportionately low rates of breastfeeding among African American women, disparities continue to exist. There is a consensus that breastfeeding has widespread health benefits for infants, mothers, and society. But socio-historical factors unique to African Americans have been largely overlooked. These are events, experiences, and other phenomena that have been culturally, socially, and generationally passed down and integrated into families, potentially influencing breastfeeding beliefs and behaviors. The goals of this study are to describe cultural factors influencing African American mothers’ perceptions of infant-feeding decisions and to identify possible connections between these socio-historical factors and African American infant-feeding outcomes. I conducted six focus groups, three breastfeeding groups and three formula-feeding groups, in May 2015 through September 2015. The groups were constructed using a purposeful sampling of African American mothers stratified by age—18–29, 30–50, and 51+. I used MAXQDA computer software to conduct a qualitative thematic analysis on the findings. This study’s findings suggest that an examination of the socio-historical factors of breastfeeding disparities may illuminate key areas that can be targeted for the development of culturally sensitive interventions to improve African American breastfeeding outcomes.
Ghost inflation and de Sitter entropy
Creators: name: Jazayeri, Sadra
name: Mukohyama, Shinji
name: Saitou, Rio
name: Watanabe, Yota
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In the setup of ghost condensation model the generalized second law of black hole thermodynamics can be respected under a radiatively stable assumption that couplings between the field responsible for ghost condensate and matter fields such as those in the Standard Model are suppressed by the Planck scale. Since not only black holes but also cosmology are expected to play important roles towards our better understanding of gravity, we consider a cosmological setup to test the theory of ghost condensation. In particular we shall show that the de Sitter entropy bound proposed by Arkani-Hamed, et.al. is satisfied if ghost inflation happened in the early epoch of our universe and if there remains a tiny positive cosmological constant in the future infinity. We then propose a notion of cosmological Page time after inflation.
Cross-sections for heavy atmospheres: H$_2$O continuum
Creators: name: Anisman, Lara O.
name: Chubb, Katy L.
name: Elsey, Jonathan
name: Al-Refaie, Ahmed
name: Changeat, Quentin
name: Yurchenko, Sergei N.
name: Tennyson, Jonathan
name: Tinetti, Giovanna
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Most of the exoplanets detected up to now transit in front of their host stars, allowing for the generation of transmission spectra; the study of exoplanet atmospheres relies heavily upon accurate analysis of these spectra. Recent discoveries mean that the study of atmospheric signals from low-mass, temperate worlds are becoming increasingly common. The observed transit depth in these planets is small and more difficult to analyze. Analysis of simulated transmission spectra for two small, temperate planets (GJ 1214 b and K2-18 b) is presented, giving evidence for significant differences in simulated transit depth when the water vapor continuum is accounted for when compared to models omitting it. These models use cross-sections from the CAVIAR lab experiment for the water self-continuum up to 10,000 cm$^{-1}$; these cross-sections exhibit an inverse relationship with temperature, hence lower-temperature atmospheres are the most significantly impacted. Including the water continuum strongly affects transit depths, increasing values by up to 80 ppm, with the differences for both planets being detectable with the future space missions Ariel and JWST. It is imperative that models of exoplanet spectra move toward adaptive cross-sections, increasingly optimized for H$_2$O-rich atmospheres. This necessitates including absorption contribution from the water vapor continuum into atmospheric simulations.
Motion and Shape Control of Soft Robots
Creators: name: Eldeeb, Ahmed E.
Publisher: name: University of Illinois at Chicago
Year: 2023

description: Unlike conventional robots, soft robots are designed to have higher number of degrees of freedom to provide higher degree of flexibility, have lower weight, and provide safe interactions with the environments. In this thesis, a new continuum-based approach for simultaneously controlling the motion and shape of soft robots and materials (SRM) is proposed based on the absolute nodal coordinate formulation. This approach allows for computing the actuation forces for arbitrary desired SRM motion and geometry. A new hybrid-actuation system for near-elimination of the small oscillations of articulated flexible-robot systems is proposed based on the floating frame of reference. This thesis discusses fundamental issues relevant to the motion and shape control of articulated robots that consist of components made of soft materials. These issues include joint formulation, geometric and material nonlinearities, and definition of torsional strains. Because in articulated systems very flexible bodies are often connected with other bodies, which have different degrees of flexibility; it is necessary to develop an efficient joint formulation. A new simple formulation of the orientation constraints for flexible bodies using two position-gradient vectors is introduced. This thesis demonstrates that, in more general beam formulations, higher stiffness can be attributed to geometric nonlinearities as result of cross-section deformations, not properly captured by the analytical or less general FE beam formulations. The effect of using different constitutive models on the stiff behavior of beams is investigated. It is demonstrated that the stiff behavior resulting from the geometric stiffening due to the coupling between the cross-section deformations and beam vibrations in more general beam formulations cannot always be interpreted as locking. This thesis introduces a new geometrically consistent plane strain and stress constitutive models for the nonlinear large-displacement analysis of soft materials using position-gradient constraints. The position gradients are used to define strain and stress constraints that enter into the formulation of the deformation tensor, strain-energy density function, and new constitutive models. The linear and nonlinear torsion-kinematic equations are also developed in this thesis using the position-gradient vectors. This thesis presents a new gradient interpretation of the linear torsion formulation, develops its governing equations, and sheds light on its assumptions.
Factors correlated with physical activity during pregnancy and associations of physical activity with spontaneous abortion, length of gestation, and birthweight
Creators: name: Jukic, Anne Marie Zaura
Publisher: name: University of North Carolina at Chapel Hill
Year: 2009

description: The first study aim was to identify characteristics associated with self-reported physical activity at 17-22 and 27-30 weeks gestation using data from the Pregnancy, Infection, and Nutrition 3 Study. Correlates of low level recreational activity were mostly sociodemographic but most sociodemographics were not also correlated with higher level recreational activity. At 27-30 weeks, overweight/obese women were less likely to engage in recreational activity. At 17-22 weeks, women who began prenatal care later and women with a history of miscarriage were less likely to engage in recreational activity. Physical activity was positively associated with partner support and enjoyment of physical activity. This analysis is limited by self-reported physical activity measures and the performance of model selection based on a p-value. These associations may help target interventions to increase activity during pregnancy. The second aim was to examine the association between vigorous physical activity and gestational age and birthweight (among term births). The third aim was to examine the association between vigorous physical activity and spontaneous abortion. Both aims used data from the Right From the Start Study, which measured vigorous physical activity at 13-16 weeks gestation. The association of total vigorous physical activity with preterm birth was U-shaped. However, vigorous recreational activity was associated with lower odds of preterm birth. Performing at least five sessions of vigorous recreational activity per week was associated with decreased odds of earlier birth (odds ratio (OR) (95% confidence interval, (CI)):0.66 (0.36, 1.21)). Women who reported starting exercise in preparation for pregnancy had lower odds of earlier birth OR(CI): 0.65 (0.45, 0.94), none gave birth preterm. Women who reported decreasing their vigorous activity from pre-pregnancy to interview had lower odds of spontaneous abortion, OR(CI): 0.44 (0.32, 0.61). We found no evidence that vigorous recreational activity was associated with adverse changes in pregnancy outcome. These analyses are limited by self-reported activity measures and low prevalence of vigorous activity. The spontaneous abortion analysis is susceptible to recall bias. Our analysis suggests that vigorous recreational activity during pregnancy may be safe. Future studies should examine the association of vigorous recreational activity with maternal injury and other perinatal outcomes.
Diagrammatic approach to cellular automata and the emergence of form with inner structure
Creators: name: García-Morales, Vladimir
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cellular Automata and Lattice Gases (nlin.CG)
subject: Mathematical Physics (math-ph)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We present a diagrammatic method to build up sophisticated cellular automata (CAs) as models of complex physical systems. The diagrams complement the mathematical approach to CA modeling, whose details are also presented here, and allow CAs in rule space to be classified according to their hierarchy of layers. Since the method is valid for any discrete operator and only depends on the alphabet size, the resulting conclusions, of general validity, apply to CAs in any dimension or order in time, arbitrary neighborhood ranges and topology. We provide several examples of the method, illustrating how it can be applied to the mathematical modeling of the emergence of order out of disorder. Specifically, we show how the the majority CA rule can be used as a building block to construct more complex cellular automata in which separate domains (with substructures having different dynamical properties) are able to emerge out of disorder and coexist in a stable manner.
description: 26 pages, 8 figures, some few minor corrections introduced to match the final, published version
Mechanisms of ligand-receptor interactions of the dopamine D2L receptor and their relation to functional selectivity
Creators: name: Fowler, Justin Corey.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Binding and functional studies indicate that some agonists are capable of differentially activating pathways linked to a single receptor isoform. In cases where known mechanisms like other receptors or receptor reserve are ruled out, this phenomenon is referred to as “functional selectivity,” “agonist directed trafficking,” and a variety of other terms. Rather than viewing receptors in a traditional way as digital entities (i.e., one or more active or inactive states), functional selectivity posits that a receptor can be induced into unique conformations that may lead to different patterns of activation of functional responses linked to a single receptor. This dissertation elucidates the molecular mechanisms that explain why some ligands can differentially activate the effector pathways coupled to the human D2L receptor. The focus will be to discern the structural interactions of the hD2L receptor with such functionally selective ligands, and how these interactions result in selective activation of effector pathways. Computationally-selected point mutations of the D2L receptor were made, and detailed analysis of both binding and function made for a series of rationally selected ligands, emphasizing compounds that were relatively rigid and had fewer degrees of freedom in possible docking poses. Functional assays tested the intrinsic activity and potency for GTPγS binding, inhibition of forskolin-stimulated cAMP, phosphorylation of MAPK, and release of [3H]-arachidonic acid. Results from this dissertation provide evidence to support the hypothesis that ligand-selective interactions with specific residues of the receptor can induce conformational changes that lead to a characteristic pattern of activation of one of more signaling pathways. Developing a structure-based understanding of functional selectivity will provide general insight into the mechanisms of GPCR activation, and may also open the door to design of small molecules with desired patterns of functional effects at a single receptor.
Tropical refined curve counting via motivic integration
Creators: name: Nicaise, Johannes
name: Payne, Sam
name: Schroeter, Franziska
Publisher: name: arXiv
Year: 2016
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We propose a geometric interpretation of Block and Göttsche's refined tropical curve counting invariants in terms of virtual $χ_{-y}$-specializations of motivic measures of semialgebraic sets in relative Hilbert schemes. We prove that this interpretation is correct for linear series of genus 1, and in arbitrary genus after specializing from $χ_{-y}$ to Euler characteristic.
description: 44 pages; 2 figures. v2: minor errors and typos corrected; Section 6 added (proof of the \delta=1 case)
Tapping opportunity of tiny shaped particles and role of precursor in developing shaped particles
Creators: name: Ali, Mubarak
name: Lin, I-Nan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Metallic colloids are frequently used in industry and provide understanding of science at microns to nanometers scales along with their applicability for various technologically important applications. Present investigations deal morphology-structure of gold, silver and their binary composition while processing the certain amount of their solutions in a newly designed process and tap opportunities of developing tiny shaped particles. At tuned ratio of pulse OFF to ON time and when gold solution was processed, several tiny shaped particles developed at solution surface. Such tiny particles deal force at the tip of each converted structure of smooth element under the steady-state immersing behavior pointing toward common centre to pack for developing different geometric anisotropic shaped particles. Under identical parameters along with pulse time, processing solutions of silver nitrate and binary composition of chloroauric acid-silver nitrate result into develop tiny particles having no specific shape where their packing deal mixed behavior of force resulting into develop distorted particles. Elongation and deformation of gold and silver atoms while in different structures is because of the plastically-driven behavior of electrons as per stretching of their clamped energy knots. In structure of three-dimensional where electrons of atoms do not deal transition require for elongation they retain the structure as it is known in hcp structure or two-dimensional structure. Different nature of precursors along with morphology-structure of particles is discussed in this paper opening abundant avenues of research.
Automorphic Lie Algebras and Cohomology of Root Systems
Creators: name: Knibbeler, Vincent
name: Lombardo, Sara
name: Sanders, Jan A.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Rings and Algebras (math.RA)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 17B05, 17B22, 17B65

description: A cohomology theory of root systems emerges naturally in the context of Automorphic Lie Algebras, where it helps formulating some structure theory questions. In particular, one can find concrete models for an Automorphic Lie Algebra by integrating cocycles. In this paper we define this cohomology and show its connection with the theory of Automorphic Lie Algebras. Furthermore, we discuss its properties: we define the cup product, we show that it can be restricted to symmetric forms, that it is equivariant with respect to the automorphism group of the root system, and finally we show acyclicity at dimension two of the symmetric part, which is exactly what is needed to find concrete models for Automorphic Lie Algebras. Furthermore, we show how the cohomology of root systems finds application beyond the theory of Automorphic Lie Algebras by applying it to the theory of contractions and filtrations of Lie algebras. In particular, we show that contractions associated to Cartan $\mathbb{Z}$-filtrations of simple Lie algebras are classified by $2$-cocycles, due again to the vanishing of the symmetric part of the second cohomology group.
description: 26 pages, standard LaTeX2e
Remotely Establishing Polarization Entanglement over Noisy Polarization Channels
Creators: name: Ecker, Sebastian
name: Sohr, Philipp
name: Bulla, Lukas
name: Ursin, Rupert
name: Bohmann, Martin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The faithful distribution of entanglement over noisy channels is a vital prerequisite for many quantum technological applications. Quantum information can be encoded in different degrees of freedom (DOF) of photons, where each encoding comes with its own advantages and disadvantages with respect to noise resilience and practicality in manipulation. In this work, we experimentally implement a deterministic entanglement purification protocol that allows us to faithfully distribute entanglement in one DOF over a noisy channel and then remotely transfer it to another DOF for manipulation. In particular, we distribute robust energy-time entanglement and transfer it to polarization entanglement at the communicating parties. The remotely obtained polarization state is independent of the polarization noise during distribution and reaches fidelities to a Bell state of up to 97.6%. Our scheme enables robust and efficient polarization entanglement distribution in the presence of arbitrary polarization noise, which is relevant for future large-scale quantum networks.
description: 7 pages, 3 figures
The Social Determinants and Health Consequences of Non-Cognitive Resources in Young Adulthood
Creators: name: Johnson, Moira
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2018

description: Non-cognitive resources (NCRs) may play a critical role in the development of socioeconomic disparities in health. However, little is known about the mechanisms through which NCRs influence health, and how these associations vary by socioeconomic status. This dissertation investigates how NCRs are formed in adolescence and young adulthood, and how NCRs relate to life course socioeconomic status, health behaviors, and physical health. Chapter two investigates the role of early life factors in shaping NCRS over the life course by examining differences in NCR ability by adolescent socioeconomic status, school-level contextual factors, and family relationship quality. Chapter three examines how NCR change is associated with health behaviors in young adulthood, including an exploration of the moderating effects of socioeconomic status (SES). Finally, chapter four investigates how NCR change is associated with physiological functioning in young adulthood, including an examination of how this association varies by SES, and whether variations in health behaviors account for some of the disparities in physical health by NCR change.
      	The findings from chapter two reveal that NCRs are malleable during the transition to adulthood, and that the extent of this malleability is strongest for planfulness and active problem solving ability. The findings from chapter two also demonstrate that life course SES is associated with the development of NCRs. Chapters three and four show that increasing planfulness is associated with a decreased likelihood of engaging in two or more health risk behaviors, and with a decreased likelihood of elevated CRP. The findings also demonstrate that the protective association of planfulness is weaker among low-SES individuals, showing support for the disabling hypothesis. Increasing attractive personality during the transition to adulthood is associated with a decreased likelihood of metabolic syndrome. The protective association of attractive personality is stronger for low-SES individuals, showing support for the resource substitution hypothesis. The findings suggest that NCRs may be important resources to intervene on to enhance health in later life. However, improving NCRs without addressing structural circumstances that make it harder to enact health-related goals may not diminish existing SES health disparities.
Adversity and Psychopathology in Youth: The Role of Sleep
Creators: name: Shields, Allison
name: Tackett, Jennifer
name: España, Raul
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences

description: This project examines moderating and mediating effects of sleep problems in the association between various forms of adversity and psychopathology in youth.
Generalized Nonlinear Yule Models
Creators: name: Lansky, Petr
name: Polito, Federico
name: Sacerdote, Laura
Publisher: name: arXiv
Year: 2016
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60G22, 60J80, 05C80

description: With the aim of considering models with persistent memory we propose a fractional nonlinear modification of the classical Yule model often studied in the context of macrovolution. Here the model is analyzed and interpreted in the framework of the development of networks such as the World Wide Web. Nonlinearity is introduced by replacing the linear birth process governing the growth of the in-links of each specific webpage with a fractional nonlinear birth process with completely general birth rates. Among the main results we derive the explicit distribution of the number of in-links of a webpage chosen uniformly at random recognizing the contribution to the asymptotics and the finite time correction. The mean value of the latter distribution is also calculated explicitly in the most general case. Furthermore, in order to show the usefulness of our results, we particularize them in the case of specific birth rates giving rise to a saturating behaviour, a property that is often observed in nature. The further specialization to the non-fractional case allows us to extend the Yule model accounting for a nonlinear growth.
Network Unfolding Map by Edge Dynamics Modeling
Creators: name: Verri, Filipe Alves Neto
name: Urio, Paulo Roberto
name: Zhao, Liang
Publisher: name: arXiv
Year: 2016
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: The emergence of collective dynamics in neural networks is a mechanism of the animal and human brain for information processing. In this paper, we develop a computational technique using distributed processing elements in a complex network, which are called particles, to solve semi-supervised learning problems. Three actions govern the particles' dynamics: generation, walking, and absorption. Labeled vertices generate new particles that compete against rival particles for edge domination. Active particles randomly walk in the network until they are absorbed by either a rival vertex or an edge currently dominated by rival particles. The result from the model evolution consists of sets of edges arranged by the label dominance. Each set tends to form a connected subnetwork to represent a data class. Although the intrinsic dynamics of the model is a stochastic one, we prove there exists a deterministic version with largely reduced computational complexity; specifically, with linear growth. Furthermore, the edge domination process corresponds to an unfolding map in such way that edges "stretch" and "shrink" according to the vertex-edge dynamics. Consequently, the unfolding effect summarizes the relevant relationships between vertices and the uncovered data classes. The proposed model captures important details of connectivity patterns over the vertex-edge dynamics evolution, in contrast to previous approaches which focused on only vertex or only edge dynamics. Computer simulations reveal that the new model can identify nonlinear features in both real and artificial data, including boundaries between distinct classes and overlapping structures of data.
description: Published version in http://ieeexplore.ieee.org/document/7762202/
Distributed Inertial Best-Response Dynamics
Creators: name: Swenson, Brian
name: Eksin, Ceyhun
name: Kar, Soummya
name: Ribeiro, Alejandro
Publisher: name: arXiv
Year: 2016
Subjects: subject: Systems and Control (eess.SY)
subject: Computer Science and Game Theory (cs.GT)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: The note considers the problem of computing pure Nash equilibrium (NE) strategies in distributed (i.e., network-based) settings. The paper studies a class of inertial best response dynamics based on the fictitious play (FP) algorithm. It is shown that inertial best response dynamics are robust to informational limitations common in distributed settings. Fully distributed variants of FP with inertia and joint strategy FP with inertia are developed and convergence is proven to the set of pure NE. The distributed algorithms rely on consensus methods. Results are validated using numerical simulations.
Assessing Exposure to and Risks of Fine Particulate Air Pollution from Multiple Sources
Creators: name: Li, Ya-Ru
Publisher: name: University of North Carolina at Chapel Hill Graduate School
Year: 2014
Subjects: Public health
Environmental sciences
Environmental health

description: While fine particulate matter (PM2.5) has long been associated with adverse health effects, relatively little is known about the differential risks posed by PM2.5 from different sources. Current U.S. regulatory approaches treat all PM2.5 as equally risky, regardless of its source. Methods identifying the most harmful particle sources are needed to improve PM2.5 control strategies and enhance protection of public health. This work develops and demonstrates a method for assessing exposure to and risks of PM2.5 from different sources in the southeastern United States and then applies this method to evaluate the benefits of a case-study state policy. This research demonstrates a new exposure assessment approach for characterizing population exposure to PM2.5 from different sources. Although emissions from power plants, biomass burning, and motor vehicles remain the leading PM2.5 sources, ambient levels of PM2.5 attributable to these sources, especially power plant emissions, have considerably declined over the past decade in areas where emission source densities are high. The results further suggest that routinely collected data on multiple air pollutants can offer valuable insights into sources of PM2.5. Using source-specific PM2.5 exposure estimates, this research introduces a new risk assessment method for quantifying health impacts attributable to different PM2.5 pollution sources. The results show that in the southeastern United States, the risk of premature death attributable to the leading air pollution sources declined between 2002 and 2012, preventing thousands of premature deaths. Finally, this work employs the new risk assessment method to evaluate the benefits of the North Carolina (NC) Clean Smokestacks Act. The combination of state and federal policies to reduce emissions from coal-fired power plants has resulted in significant improvements in air quality and health in NC, and the Clean Smokestacks Act benefited air quality and health beyond the benefits of federal legislation alone. While current regulatory approaches overlook the potential of source effects, this research demonstrates an integrated method to improve PM2.5 control strategies. Future research should evaluate the potential for the development of techniques to combine the best qualities of existing data and methods and continued toxicological and epidemiologic evaluation to support source-based PM2.5 risk assessment.
Valley polarization control in WSe2 monolayer by a single-cycle laser pulse
Creators: name: Hashmi, Arqum
name: Yamada, Shunsuke
name: Yamada, Atsushi
name: Yabana, Kazuhiro
name: Otobe, Tomohito
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Abstract The valley degree of freedom in two-dimensional materials provides an opportunity to extend the functionalities of valleytronics devices. Very short valley lifetimes demand the ultrafast control of valley pseudospin. Here, we theoretically demonstrate the control of valley pseudospin in WSe2 monolayer by single-cycle linearly polarized laser pulse. We use the asymmetric electric field controlled by the carrier-envelope phase (CEP) to make the valley polarization between K and K'-point in the Brillouin zone (BZ). Time-dependent density functional theory with spin-orbit interaction reveals that no valley asymmetry and its CEP dependence is observed within the linear-optical limit. In the nonlinear-optical regime, linearly polarized pulse induces a high degree of valley polarization and this polarization is robust against the field strength. Valley polarization strongly depends and oscillates as a function of CEP. The carrier density distribution forms nodes as the laser intensity increases, our results indicate that the position of the carrier density in the BZ can be controlled by the laser intensity. From the analysis by the massive Dirac Hamiltonian model, the nodes of the carrier density can be attributed to the Landau-Zener-Stückelberg interference of wave packets of the electron wave function.
THE DEVELOPMENT OF A TOOL TO ASSESS INDIVIDUAL PROVIDER'S CULTURAL COMPETENCE
Creators: name: Thaker, Samruddhi
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: This study examined the validity of the policy-driven notion that patient centeredness, patient-doctor relationship, patient-doctor communication, and cultural competency represent four distinct but related domains of patient experience of care. Guided by the quality of the service experience framework, I proposed an alternative conceptualization that these domains are empirically highly related with each other and can be conceptualized as the one-dimensional construct of patient experience of the interpersonal aspects of care. Twenty-four items from the Commonwealth Fund 2001 Health Care Quality Survey were identified as measures of the four domains. Two measurement models -- four-factor and one-factor models -- were developed to represent the alternative conceptualizations. Using structural equation modeling techniques, data drawn from the Commonwealth Fund 2001 Health Care Quality Survey were analyzed to examine the factor structure underlying these items. Findings provide strong evidence that patient centeredness, patient-doctor relationship, patient-doctor communication, and cultural competency are empirically highly related and can be conceptualized as a one-dimensional construct. This one-domain conceptualization holds across males and females and across four racial/ethnic groups for the English-proficient population. It also holds for the non-English speaking/Limited English-proficient population. Construct validity of this one-domain conceptualization was supported by evidence of positive association between measures of the four domains and measures of access to care and healthcare outcomes. Drawing upon the quality of the service experience framework, I conclude that the four domains -- patient centeredness, patient-doctor relationship, patient-doctor communication, and cultural competency -- can be conceptualized as the patient experience of the interpersonal aspects of care. The measures of the four domains form a 10-item and 11-item one-dimensional scale for English-proficient and non-English speaking/Limited English-proficient populations, respectively. This scale demonstrated adequate internal consistency reliability. Taken together, the consistency of findings suggests that the one-domain conceptualization of patient centeredness, patient-doctor relationship, patient-doctor communication, and cultural competency is valid and has considerable generality. Policymakers and program developers and evaluators should define, conceptualize, and measure the four domains as the patient experience of the interpersonal aspects of care. Future studies should replicate the validity of this one-domain conceptualization and examine the dimensionality and psychometric properties of the scale.
Adaptive estimation for financial time series
Creators: name: Mercurio, Danilo
Publisher: name: Humboldt-Universität zu Berlin, Wirtschaftswissenschaftliche Fakultät
Year: 2004
Subjects: subject: adaptive Schaetzung
subject: lokale Homogenitaet
subject: Finanzmarktdaten
subject: Vorhersage
subject: adaptive estimation
subject: local homogeneity
subject: financial data
subject: forecasting
subject: 330 Wirtschaft
subject: 17 Wirtschaft

description: Diese Dissertation entwickelt neue lokal adaptive Methoden zur Schaetzung und Vorhersage von Zeitreihendaten. Diese Methoden sind fuer die Volatilitaetsschaetzung von Finanzmarktrenditen und fuer Regressions- und Autoregressionsprobleme konstruiert worden. Die vorgeschlagenen Ansaetze werden als lokal adaptiv bezeichnet, denn, anstatt einen globalen datenerzeugenden Prozess aufzuzwingen, welcher durch eine endliche Anzahl von Parametern beschrieben werden kann, nehmen sie nur an, dass Beobachtungen, welche chronologisch nah bei einander liegen, durch einen konstanten Prozess gut approximiert werden koennen. Diese Prozeduren sind adaptiv, weil sie fuer jede Beobachtung in einer datengesteuerten Art und Weise das Intervall der Zeithomogenitaet,d.h. die Anzahl der chronologisch benachbarten und homogen vergangenen Daten, aussuchen, fuer welchen die Hypothese einer konstanten Struktur nicht verworfen werden kann. Nichtasymptotische theoretische Ergebnisse werden hergeleitet, welche die Optimalitaet der betrachteten Algorithmen zeigen. Vergleiche mit Standardansaetzen verdeutlichen, dass die neuen Prozeduren sich kompetitiv verhalten und eine nuetzliche Alternative bieten, ausserdem liefern intensive Simulationsstudien und Anwendungen an reellen Daten gute Ergebnisse und bezeugen dabei ihre Effektivitaet und praktische Relevanz.
description: This thesis develops new locally adaptive methods for estimation and forecasting of financial time series data. These methods are mainly tailored for volatility estimation of financial returns and for regression and autoregression problems. The proposed approaches are defined locally adaptive because instead of imposing a stationary data generating process which can be globally described by a finite number of parameters, they only assume that observations which are chronologically close to each other can be well approximated by a constant process. These procedures are adaptive in the sense that for each observation they choose in a data driven way the interval of time homogeneity, i.e. the number of chronologically close and homogeneous past data where the hypothesis of a constant structure can not be rejected. Nonasymptotic theoretical results are derived, which show the optimality of the suggested algorithms. Comparisons with standard approaches demonstrate that the new procedures behave competitively and offer a valuable alternative, furthermore, intensive simulation studies and applications to real data provide good results, confirming their effectiveness and practical relevance.
Temperature dependence of the threshold magnetic field for nucleation and domain wall propagation in an inhomogeneous structure with grain boundary
Creators: name: Mohakud, Sasmita
name: Andraus, Sergio
name: Nishino, Masamichi
name: Sakuma, Akimasa
name: Miyashita, Seiji
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In order to study the dependence of the coercive force of sintered magnets on temperature, nucleation and domain wall propagation at the grain boundary are studied as rate-determining processes of the magnetization reversal phenomena in magnets consisting of bulk hard magnetic grains contacting via grain boundaries of a soft magnetic material. These systems have been studied analytically for a continuum model at zero temperature (A. Sakuma, et al. J. Mag. Mag. Mat. {\bf 84} 52 (1990)). In the present study, the temperature dependence is studied by making use of the stochastic Landau-Lifshitz-Gilbert equation at finite temperatures. In particular, the threshold fields for nucleation and domain wall propagation are obtained as functions of ratios of magnetic interactions and anisotropies of the soft and hard magnets for various temperatures. It was found that the threshold field for domain wall propagation is robust against thermal fluctuations, while that for nucleation is fragile. The microscopic mechanisms of the observed temperature dependence are discussed.
description: RevTeX4-1, 30 pages, 15 figures, corrected for submission to Phys. Rev. B
Stochastic singular control problems with state constraint
Creators: name: Ross, Kevin J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Singular control is an important and challenging class of problems in stochastic control theory. Such control problems can rarely be solved explicitly and thus numerical approximation schemes are necessary. In this work we develop approximation schemes for singular control problems with state constraints. The first problem we consider arises in problems of optimal consumption and investment under transaction costs. We use Markov chain approximations to develop a convergent numerical scheme. Proof of convergence uses techniques from the theory of weak convergence. Specific features that make the analysis nontrivial include unboundedness of state and control spaces and cost function; degeneracies in the dynamics; and presence of both singular and absolutely continuous controls. We present a computational algorithm and the results of a numerical study. Numerical schemes for singular control problems can be computationally quite intensive, and thus it is of great interest to develop less expensive schemes that exploit specific features of the underlying dynamics. To this end we investigate connections between singular control and optimal stopping problems. A key technical step in establishing such connections is proving existence of an optimal singular control. We prove such a result for a general class of singular control problems with linear dynamics and state constrained to be in a polyhedral cone. A particular example of this class of models are the so-called Brownian control problems (BCPs) and thus existence of optimal controls for BCPs follows as a consequence. Armed with this existence result, we consider a two-dimensional singular control problem that arises from queueing networks. We prove rigorously an equivalence of this iii problem with an optimal stopping problem. We exploit this connection in developing simple computational schemes for the singular control problem, and we investigate performance of the schemes in a numerical study.
From primary sequence to static and dynamic RNA tertiary structures
Creators: name: Gherghe, Costin M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: RNA molecules fold back on themselves to form complex secondary and tertiary structures. Knowledge of the three-dimensional fold as well as the underlying dynamics is essential to understand sequence-function relationships in RNA. A novel technique, called SHAPE chemistry, has been created for determining RNA secondary structure. In this work, I expand the applications of SHAPE chemistry in two directions: calculating opening rates for slow moving nucleotides and analysis of RNA dynamics at nucleotide resolution. First, I use SHAPE to identify a novel class of slow-moving nucleotides and calculate their opening rates. The major mechanism is that certain C2[prime]-endo nucleotides have slow, seconds long, opening rates. Second, I find a strong correlation between SHAPE chemistry and molecular order as measured by 13C NMR relaxation experiments. This finding validates SHAPE as an adequate substitute for 13C NMR relaxation experiments, expanding nucleotide-resolution dynamics analysis to large RNAs, inaccessible to NMR methods. Finally, I develop a fast, fully automated modeling method to determine three-dimensional structures of RNAs. This method blends (1) SHAPE-derived secondary structure information; (2) biochemical experiments that yield high quality tertiary structure information with (3) a coarse-grained molecular dynamics refinement. It therefore does not require any prior assumptions about secondary or tertiary structure, establishing the foundation for modeling and refining large RNAs inaccessible to crystallography and NMR techniques.