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The surprisingly large value of r, the ratio of power in tensor to scalar density perturbations in the CMB reported by the BICEP2 Collaboration, if confirmed, provides strong evidence for Inflation at the GUT scale. While the Inflationary signal remains the best motivated source, a large value of r alone

The surprisingly large value of r, the ratio of power in tensor to scalar density perturbations in the CMB reported by the BICEP2 Collaboration, if confirmed, provides strong evidence for Inflation at the GUT scale. While the Inflationary signal remains the best motivated source, a large value of r alone would still allow for the possibility that a comparable gravitational wave background might result from a self ordering scalar field (SOSF) transition that takes place later at somewhat lower energy. We find that even without detailed considerations of the predicted BICEP signature of such a transition, simple existing limits on the isocurvature contribution to CMB anisotropies would definitively rule out a contribution of more than 5% to r = 0.2. We also present a general relation for the allowed fractional SOSF contribution to r as a function of the ultimate measured value of r. These results point strongly not only to an inflationary origin of the BICEP2 signal, if confirmed, but also to the fact that if the GUT scale is of order 1016 GeV then either the GUT transition happens before Inflation or the Inflationary transition and the GUT transition must be one and the same.

ContributorsDent, James B. (Author) / Krauss, Lawrence (Author) / Mathur, Harsh (Author) / College of Liberal Arts and Sciences (Contributor)
Created2014-07-30
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Institutions, the rules of the game that shape repeated human interactions, clearly play a critical role in helping groups avoid the inefficient use of shared resources such as fisheries, freshwater, and the assimilative capacity of the environment. Institutions, however, are intimately intertwined with the human, social, and biophysical context within

Institutions, the rules of the game that shape repeated human interactions, clearly play a critical role in helping groups avoid the inefficient use of shared resources such as fisheries, freshwater, and the assimilative capacity of the environment. Institutions, however, are intimately intertwined with the human, social, and biophysical context within which they operate. Scholars typically are careful to take this context into account when studying institutions and Ostrom’s Institutional Design Principles are a case in point. Scholars have tested whether Ostrom’s Design Principles, which specify broad relationships between institutional arrangements and context, actually support successful governance of shared resources. This article further contributes to this line of research by leveraging the notion of institutional design to outline a research trajectory focused on coupled infrastructure systems in which institutions are seen as one class of infrastructure among many that dynamically interact to produce outcomes over time.

ContributorsAnderies, John (Author) / Janssen, Marco (Author) / Schlager, Edella (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-09-23
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The number and variety of connectivity estimation methods is likely to continue to grow over the coming decade. Comparisons between methods are necessary to prune this growth to only the most accurate and robust methods. However, the nature of connectivity is elusive with different methods potentially attempting to identify different

The number and variety of connectivity estimation methods is likely to continue to grow over the coming decade. Comparisons between methods are necessary to prune this growth to only the most accurate and robust methods. However, the nature of connectivity is elusive with different methods potentially attempting to identify different aspects of connectivity. Commonalities of connectivity definitions across methods upon which base direct comparisons can be difficult to derive. Here, we explicitly define “effective connectivity” using a common set of observation and state equations that are appropriate for three connectivity methods: dynamic causal modeling (DCM), multivariate autoregressive modeling (MAR), and switching linear dynamic systems for fMRI (sLDSf). In addition while deriving this set, we show how many other popular functional and effective connectivity methods are actually simplifications of these equations. We discuss implications of these connections for the practice of using one method to simulate data for another method. After mathematically connecting the three effective connectivity methods, simulated fMRI data with varying numbers of regions and task conditions is generated from the common equation. This simulated data explicitly contains the type of the connectivity that the three models were intended to identify. Each method is applied to the simulated data sets and the accuracy of parameter identification is analyzed. All methods perform above chance levels at identifying correct connectivity parameters. The sLDSf method was superior in parameter estimation accuracy to both DCM and MAR for all types of comparisons.

ContributorsSmith, Jason F. (Author) / Chen, Kewei (Author) / Pillai, Ajay S. (Author) / Horwitz, Barry (Author) / College of Liberal Arts and Sciences (Contributor)
Created2013-05-14
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Description

STEM classrooms (science, technology, engineering, and mathematics) in postsecondary education are rapidly improved by the proper use of active learning techniques. These techniques occupy a descriptive spectrum that transcends passive teaching toward active, constructive, and, finally, interactive methods. While aspects of this framework have been examined, no large-scale or actual

STEM classrooms (science, technology, engineering, and mathematics) in postsecondary education are rapidly improved by the proper use of active learning techniques. These techniques occupy a descriptive spectrum that transcends passive teaching toward active, constructive, and, finally, interactive methods. While aspects of this framework have been examined, no large-scale or actual classroom-based data exist to inform postsecondary education STEM instructors about possible learning gains. We describe the results of a quasi-experimental study to test the apex of the ICAP framework (interactive, constructive, active, and passive) in this ecological classroom environment. Students in interactive classrooms demonstrate significantly improved learning outcomes relative to students in constructive classrooms. This improvement in learning is relatively subtle; similar experimental designs without repeated measures would be unlikely to have the power to observe this significance. We discuss the importance of seemingly small learning gains that might propagate throughout a course or departmental curriculum, as well as improvements with the necessity for faculty to develop and implement similar activities.

ContributorsWiggins, Benjamin L. (Author) / Eddy, Sarah L. (Author) / Grunspan, Daniel (Author) / Crowe, Alison J. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-04-01
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Description

Soliman et al. (2013) set out to demonstrate how the bodily level of analysis can unify explanations in psychology. Our argument was that common sensorimotor mechanisms underlie many of the behavioral phenomena that are currently segregated as cognitive, social, or cultural. Toward that end, we re-characterized a cultural construct—self-construal along

Soliman et al. (2013) set out to demonstrate how the bodily level of analysis can unify explanations in psychology. Our argument was that common sensorimotor mechanisms underlie many of the behavioral phenomena that are currently segregated as cognitive, social, or cultural. Toward that end, we re-characterized a cultural construct—self-construal along the dimension of independence and interdependence (Markus and Kitayama, 1991)—as reflecting degree of interaction with ethnically diverse others.

ContributorsSoliman, Tamer (Author) / Glenberg, Arthur (Author) / College of Liberal Arts and Sciences (Contributor)
Created2014-06-04
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Indigenous populations are generally reported to suffer greater active tuberculosis (TB) disease burden. The objective of this study was to examine ecological associations between cases of active adult and pediatric TB reported from 2002 to 2004 and community characteristics in indigenous communities of the Paraguayan Chaco. Adult and pediatric models

Indigenous populations are generally reported to suffer greater active tuberculosis (TB) disease burden. The objective of this study was to examine ecological associations between cases of active adult and pediatric TB reported from 2002 to 2004 and community characteristics in indigenous communities of the Paraguayan Chaco. Adult and pediatric models were examined by negative binomial and Poisson GLM regression, respectively. Active TB prevalence in indigenous people was eight times higher than the nonindigenous population. Communities with a health post were more than twice as likely to report active adult TB (RR = 2.07, 95% confidence interval (CI) [1.14–3.83], and p < 0.05). Each additional average year of education in the community was associated with nearly 50% less likelihood of active pediatric TB (RR = 0.53, 95% CI [0.38–0.73], and p < 0.001). Although nonsignificant, the presence of nonindigenous community members had a strong protective association in both the adult (RR = 0.56, 95% CI [0.30–1.03], and p = 0.6) and pediatric models (RR = 0.64, 95% CI [0.34–1.14], and p = 0.14). These results reinforce the importance of increasing epidemiologic surveillance and investigating the social determinants of TB disease among vulnerable indigenous populations.

ContributorsVansteelandt, Amanda (Author) / Hurtado, Ana (Author) / Rolon, Miriam (Author) / Rojas de Arias, Antonieta (Author) / Jara, Juan Carlos (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-11-10
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Description

Tree-like structures are ubiquitous in nature. In particular, neuronal axons and dendrites have tree-like geometries that mediate electrical signaling within and between cells. Electrical activity in neuronal trees is typically modeled using coupled cable equations on multi-compartment representations, where each compartment represents a small segment of the neuronal membrane. The

Tree-like structures are ubiquitous in nature. In particular, neuronal axons and dendrites have tree-like geometries that mediate electrical signaling within and between cells. Electrical activity in neuronal trees is typically modeled using coupled cable equations on multi-compartment representations, where each compartment represents a small segment of the neuronal membrane. The geometry of each compartment is usually defined as a cylinder or, at best, a surface of revolution based on a linear approximation of the radial change in the neurite. The resulting geometry of the model neuron is coarse, with non-smooth or even discontinuous jumps at the boundaries between compartments. We propose a hyperbolic approximation to model the geometry of neurite compartments, a branched, multi-compartment extension, and a simple graphical approach to calculate steady-state solutions of an associated system of coupled cable equations. A simple case of transient solutions is also briefly discussed.

Created2014-07-09
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The genus Apodrosus Marshall is newly recorded for, and revised for Cuba. Nine new species are recognized as follows: Apodrosus alberti (type locality, Granma, Parque Nacional Pico Turquino), A. alternatus (type locality, Guantánamo, El Yunque), A. franklyni (type locality, Cienfuegos, Parque Nacional Pico San Juan), A. griseus (type locality, Santiago

The genus Apodrosus Marshall is newly recorded for, and revised for Cuba. Nine new species are recognized as follows: Apodrosus alberti (type locality, Granma, Parque Nacional Pico Turquino), A. alternatus (type locality, Guantánamo, El Yunque), A. franklyni (type locality, Cienfuegos, Parque Nacional Pico San Juan), A. griseus (type locality, Santiago de Cuba, Siboney-Jutici Ecological Reserve), A. mensurensis (type locality, Holguin, Parque Nacional La Mensura-Piloto), A. pseudoalternatus (type locality, Matanzas, Varahicacos), A. beckeli (type locality, Guantánamo, 8 km W. Imias), A. sandersoni (type locality, Guantánamo, Loma Lafarola), and A. zayasi (type locality, Cienfuegos, Parque Nacional Pico San Juan). A key for their identification, descriptions, summaries of natural history information and data on distributions are presented. A molecular phylogeny based on 11 species of Apodrosus from Cuba, Hispaniola and Puerto Rico is reconstructed. A sister group relationship between Polydrusus and Apodrosus is recovered with a limited sampling of the former genus. The monophyly of Apodrosus is recovered with strong support. Cuban Apodrosus are not monophyletic. Five of the six sampled Cuban species form a clade, sister to an undescribed Apodrosus species from the Dominican Republic; and, Apodrosus alternatus is sister to A. quisqueyanus Girón & Franz, 2010, a species from the Dominican Republic. Biogeographic implications for Cuban species are discussed in light of the phylogeny.

ContributorsAnderson, Robert S. (Author) / Zhang, Guanyang (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-06-12
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Description

The termites evolved eusociality and complex societies before the ants, but have been studied much less. The recent publication of the first two termite genomes provides a unique comparative opportunity, particularly because the sequenced termites represent opposite ends of the social complexity spectrum. Zootermopsis nevadensis has simple colonies with totipotent

The termites evolved eusociality and complex societies before the ants, but have been studied much less. The recent publication of the first two termite genomes provides a unique comparative opportunity, particularly because the sequenced termites represent opposite ends of the social complexity spectrum. Zootermopsis nevadensis has simple colonies with totipotent workers that can develop into all castes (dispersing reproductives, nest-inheriting replacement reproductives, and soldiers). In contrast, the fungus-growing termite Macrotermes natalensis belongs to the higher termites and has very large and complex societies with morphologically distinct castes that are life-time sterile. Here we compare key characteristics of genomic architecture, focusing on genes involved in communication, immune defenses, mating biology and symbiosis that were likely important in termite social evolution. We discuss these in relation to what is known about these genes in the ants and outline hypothesis for further testing.

ContributorsKorb, Judith (Author) / Poulsen, Michael (Author) / Hu, Haofu (Author) / Li, Cai (Author) / Boomsma, Jacobus J. (Author) / Zhang, Guojie (Author) / Liebig, Juergen (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-03-04
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Description

The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed

The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed information on the rocks, soils and atmosphere in this region. CheMin is a miniaturized X-ray diffraction/X-ray fluorescence (XRD/XRF) instrument that uses transmission geometry with an energy-discriminating CCD detector. CheMin uses onboard standards for XRD and XRF calibration, and beryl:quartz mixtures constitute the primary XRD standards. Four samples have been analysed by CheMin, namely a soil sample, two samples drilled from mudstones and a sample drilled from a sandstone. Rietveld and full-pattern analysis of the XRD data reveal a complex mineralogy, with contributions from parent igneous rocks, amorphous components and several minerals relating to aqueous alteration. In particular, the mudstone samples all contain one or more phyllosilicates consistent with alteration in liquid water. In addition to quantitative mineralogy, Rietveld refinements also provide unit-cell parameters for the major phases, which can be used to infer the chemical compositions of individual minerals and, by difference, the composition of the amorphous component.

ContributorsBish, David (Author) / Blake, David (Author) / Vaniman, David (Author) / Sarrazin, Philippe (Author) / Bristow, Thomas (Author) / Achilles, Cherie (Author) / Dera, Przemyslaw (Author) / Chipera, Steve (Author) / Crisp, Joy (Author) / Downs, R. T. (Author) / Farmer, Jack (Author) / Gailhanou, Marc (Author) / Ming, Doug (Author) / Morookian, John Michael (Author) / Morris, Richard (Author) / Morrison, Shaunna (Author) / Rampe, Elizabeth (Author) / Treiman, Allan (Author) / Yen, Albert (Author) / College of Liberal Arts and Sciences (Contributor)
Created2014-10-21