A Historical Perspective of Georgia's Economy

This report chronicles the history of Georgia's economy from the 1950s to the present and provides an outlook for the future growth areas in Georgia. FRC Report 10

Mathematically Modeling the Lexicon Entropy of Emergent Language

We formulate a stochastic process, FiLex, as a mathematical model of lexicon entropy in deep learning-based emergent language systems. Defining a model mathematically allows it to generate clear predictions which can be directly and decisively tested. We empirically verify across four different environments that FiLex predicts the correct correlation between hyperparameters (training steps, lexicon size, learning rate, rollout buffer size, and Gumbel-Softmax temperature) and the emergent language's entropy in 20 out of 20 environment-hyperparameter combinations. Furthermore, our experiments reveal that different environments show diverse relationships between their hyperparameters and entropy which demonstrates the need for a model which can make well-defined predictions at a precise level of granularity.Comment: 12 pages, 3 figures; added link to GitHub rep

Student Perceptions And Performance: The Use Of An Online Textbook With An Integrated Web-Based Homework Management Product

This paper presents results of a survey of student perceptions of the use of an online text combined with a homework management product (Aplia). A majority of the students taking the undergraduate economics courses in our sample (58%) disliked using the online textbook combined with the Aplia product. On the other hand, an even greater percentage of students (64%) felt that the utilization of the online textbook combined with Aplia assignments did require that they spend more time studying economics. Using a basic regression model, we then tested to determine if the use of an online textbook combined with Aplia had any impact on student performance. The data for this analysis were obtained from four sections of introductory economics. Two classes used the online textbook combined with Aplia while the other two sections utilized a standard textbook with no online component. Controlling for factors such as the instructor, gender, race, age, and SAT scores of the students, we found that the use of the online textbook combined with Aplia resulted in a negative (but insignificant) impact on student performance. Significant factors impacting student performance include past GPA, age, and the verbal SAT score. It is our view, that as faculty more effectively integrate online materials into courses and students become more comfortable utilizing online materials, student perceptions and performance will both be positively impacted

Angiotensin in ECMO patients with refractory shock

https://deepblue.lib.umich.edu/bitstream/2027.42/146149/1/13054_2018_Article_2225.pd

Solubility and selectivity effects of the anion on the adsorption of different heavy metal ions onto chitosan

The biopolymer chitosan is a very efficient adsorber material for the removal of heavy metal ions from aqueous solutions. Due to the solubility properties of chitosan it can be used as both a liquid adsorber and a solid flocculant for water treatment reaching outstanding adsorption capacities for a number of heavy metal ions. However, the type of anion corresponding to the investigated heavy metal ions has a strong influence on the adsorption capacity and sorption mechanism on chitosan. In this work, the adsorption capacity of the heavy metal ions manganese, iron, cobalt, nickel, copper, and zinc were investigated in dependence on their corresponding anions sulfate, chloride, and nitrate by batch experiments. The selectivity of the different heavy metal ions was analyzed by column experiments. © 2020 by the authors

Cosmic Microwave Background Dipole induced by double inflation

The observed CMBR dipole is generally interpreted as the consequence of the peculiar motion of the Sun with respect to the reference frame of the CMBR. This article proposes an alternative interpretation in which the observed dipole is the result of isocurvature perturbations on scales larger than the present Hubble radius. These perturbations are produced in the simplest model of double inflation, depending on three parameters. The observed dipole and quadrupole can be explained in this model, while severely constraining its parameters.Comment: Latex, 9 pages, no figure, to appear in Phys. Rev.

Oxidative Stress and Inflammatory Modulation of Ca2+ Handling in Metabolic HFpEF-Related Left Atrial Cardiomyopathy

Metabolic syndrome-mediated heart failure with preserved ejection fraction (HFpEF) is commonly accompanied by left atrial (LA) cardiomyopathy, significantly affecting morbidity and mortality. We evaluate the role of reactive oxygen species (ROS) and intrinsic inflammation (TNF-α, IL-10) related to dysfunctional Ca2+ homeostasis of LA cardiomyocytes in a rat model of metabolic HFpEF. ZFS-1 obese rats showed features of HFpEF and atrial cardiomyopathy in vivo: increased left ventricular (LV) mass, E/e' and LA size and preserved LV ejection fraction. In vitro, LA cardiomyocytes exhibited more mitochondrial-fission (MitoTracker) and ROS-production (H2DCF). In wildtype (WT), pro-inflammatory TNF-α impaired cellular Ca2+ homeostasis, while anti-inflammatory IL-10 had no notable effect (confocal microscopy; Fluo-4). In HFpEF, TNF-α had no effect on Ca2+ homeostasis associated with decreased TNF-α receptor expression (western blot). In addition, IL-10 substantially improved Ca2+ release and reuptake, while IL-10 receptor-1 expression was unaltered. Oxidative stress in metabolic syndrome mediated LA cardiomyopathy was increased and anti-inflammatory treatment positively affected dysfunctional Ca2+ homeostasis. Our data indicates, that patients with HFpEF-related LA dysfunction might profit from IL-10 targeted therapy, which should be further explored in preclinical trials

When kinases meet mathematics: the systems biology of MAPK signalling

The mitogen activated protein kinase/extracellular signal regulated kinase pathway regulates fundamental cellular function such as cell proliferation, survival, differentiation and motility, raising the question how these diverse functions are specified and coordinated. They are encoded through the activation kinetics of the pathway, a multitude of feedback loops, scaffold proteins, subcellular compartmentalisation, and crosstalk with other pathways. These regulatory motifs alone or in combination can generate a multitude of complex behaviour. Systems biology tries to decode this complexity through mathematical modelling and prediction in order to gain a deeper insight into the inner works of signalling networks

Starburst Galaxies and the X-Ray Background

Integrated X-ray spectra of an evolving population of starburst galaxies (SBGs) are determined based on the observed spectra of local SBGs. In addition to emission from hot gas and binary systems, our model SBG spectrum includes a nonthermal component from Compton scattering of relativistic electrons by the intense ambient far-IR and the (steeply evolving) CMB radiation fields. We use these integrated spectra to calculate the levels of contribution of SBGs to the cosmic X-ray background assuming that their density evolves as (1+z)^q up to a maximal redshift of 5. We find that at energies <10 keV this contribution is at a level of few percent for q up to 3, and in the range of 5%-15% for q ~ 4.5. The Compton component is predicted to be the main SBG emission at high energies, and its relative contribution gets progressively higher for increasing redshift.Comment: 10 pages, 5 figures; accepted for publication in A&