Physics Commons^™

Automated Annotation Of Functional Imaging Experiments Via Multi-Label Classification, Matthew D. Turner, Chayan Chakrabarti, Thomas B. Jones, Jiawei F. Xu, Peter T. Fox, George F. Luger, Angela Laird, Jessica A. Turner

Department of Physics

Identifying the experimental methods in human neuroimaging papers is important for grouping meaningfully similar experiments for meta-analyses. Currently, this can only be done by human readers. We present the performance of common machine learning (text mining) methods applied to the problem of automatically classifying or labeling this literature. Labeling terms are from the Cognitive Paradigm Ontology (CogPO), the text corpora are abstracts of published functional neuroimaging papers, and the methods use the performance of a human expert as training data. We aim to replicate the expert's annotation of multiple labels per abstract identifying the experimental stimuli, cognitive paradigms, response types, …

Determination Of The Top-Quark Pole Mass And Strong Coupling Constant From The T T-Bar Production Cross Section In Pp Collisions At Sqrt(S) = 7 Tev, Cms Collaboration, Vanessa Gaultney, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The inclusive cross section for top-quark pair production measured by the CMS experiment in proton–proton collisions at a center-of-mass energy of 7 TeV is compared to the QCD prediction at next-to-next-to-leading order with various parton distribution functions to determine the top-quark pole mass, m[pole over t], or the strong coupling constant, α[subscript S]. With the parton distribution function set NNPDF2.3, a pole mass of 176.7[+3.8 over −3.4] GeV is obtained when constraining α[subscript S] at the scale of the Z boson mass, m[subscript Z], to the current world average. Alternatively, by constraining m[pole over t] to the latest average from …

Development Of Effective Approaches To The Large-Scale Aerodynamic Testing Of Low-Rise Building, Tuan-Chun Fu

FIU Electronic Theses and Dissertations

Low-rise buildings are often subjected to high wind loads during hurricanes that lead to severe damage and cause water intrusion. It is therefore important to estimate accurate wind pressures for design purposes to reduce losses. Wind loads on low-rise buildings can differ significantly depending upon the laboratory in which they were measured. The differences are due in large part to inadequate simulations of the low-frequency content of atmospheric velocity fluctuations in the laboratory and to the small scale of the models used for the measurements. A new partial turbulence simulation methodology was developed for simulating the effect of low-frequency flow …

Extending Positive Class Results Across Multiple Instructors And Multiple Classes Of Modeling Instruction, Eric Brewe, Adrienne Traxler, Jorge De La Garza, Laird Kramer

Department of Physics

We report on a multiyear study of student attitudes measured with the Colorado Learning Attitudes about Science Survey in calculus-based introductory physics taught with the Modeling Instruction curriculum. We find that five of six instructors and eight of nine sections using Modeling Instruction showed significantly improved attitudes from pre- to postcourse. Cohen’s d effect sizes range from 0.08 to 0.95 for individual instructors. The average effect was d=0.45, with a 95% confidence interval of (0.26–0.64). These results build on previously published results showing positive shifts in attitudes from Modeling Instruction classes. We interpret these data in light of other published …

Adult Age-Dependent Differences In Resting-State Connectivity Within And Between Visual-Attention And Sensorimotor Networks, Christian Roski, Svenja Caspers, Robert Langner, Angela Laird, Peter Fox, Karl Zilles, Katrin Amunts, Simon Eichhoff

Department of Physics

Healthy aging is accompanied by structural and functional changes in the brain, among which a loss of neural specificity (i.e., dedifferentiation) is one of the most consistent findings. Little is known, however, about changes in interregional integration underlying a dedifferentiation across different functional systems. In a large sample (n = 399) of healthy adults aged from 18 to 85 years, we analyzed age-dependent differences in resting-state (RS) (task-independent) functional connectivity (FC) of a set of brain regions derived from a previous fMRI study. In that study, these regions had shown an age-related loss of activation specificity in visual-attention (superior …

Factors That Affect The Physical Science Career Interest Of Female Students: Testing Five Common Hypotheses, Zahra Hazari, Geoff Potvin, Robynne M. Lock, Florin Lung, Gerhard Sonnert, Philip M. Sadler

Department of Teaching and Learning

There are many hypotheses regarding factors that may encourage female students to pursue careers in the physical sciences. Using multivariate matching methods on national data drawn from the Persistence Research in Science and Engineering (PRiSE) project (n=7505), we test the following five commonly held beliefs regarding what factors might impact females’ physical science career interest: (i) having a single-sex physics class, (ii) having a female physics teacher, (iii) having female scientist guest speakers in physics class, (iv) discussing the work of female scientists in physics class, and (v) discussing the underrepresentation of women in physics class. The effect of these …

Tubular And Sector Heat Pipes With Interconnected Branches For Gas Turbine And/Or Compressor Cooling, Brian D. Reding Ii

FIU Electronic Theses and Dissertations

Designing turbines for either aerospace or power production is a daunting task for any heat transfer scientist or engineer. Turbine designers are continuously pursuing better ways to convert the stored chemical energy in the fuel into useful work with maximum efficiency. Based on thermodynamic principles, one way to improve thermal efficiency is to increase the turbine inlet pressure and temperature. Generally, the inlet temperature may exceed the capabilities of standard materials for safe and long-life operation of the turbine. Next generation propulsion systems, whether for new supersonic transport or for improving existing aviation transport, will require more aggressive cooling system …

Distribution Of Light In The Human Retina Under Natural Viewing Conditions, Jorge C. Gibert

FIU Electronic Theses and Dissertations

Age-related macular degeneration (AMD) is the leading cause of blindness inAmerica. The fact that AMD wreaks most of the damage in the center of the retina raises the question of whether light, integrated over long periods, is more concentrated in the macula.

A method, based on eye-tracking, was developed to measure the distribution of light in the retina under natural viewing conditions. The hypothesis was that integrated over time, retinal illumination peaked in the macula. Additionally a possible relationship between age and retinal illumination was investigated.

The eye tracker superimposed the subject’s gaze position on a video recorded by a …

Talking And Learning Physics: Predicting Future Grades From Network Measures And Force Concept Inventory Pretest Scores, Jesper Bruun, Eric Brewe

Department of Physics

We present a method of analyzing the development of self-efficacy in real time using a framework of self-efficacy opportunities (SEOs). Considerable research has shown a connection between self-efficacy, or the confidence in one’s own ability to perform a task, and success in science fields. Traditional methods of investigating the development of self-efficacy have required participants to recollect past events. This reliance on participant memory makes it difficult to understand what impact particular events may have on developing self-efficacy in the moment. We use video recordings of three undergraduate Modeling Instruction students solving a physics problem to characterize SEOs in a …

An Ethnographic Study: Becoming A Physics Expert In A Biophysics Research Group, Idaykis Rodriguez

FIU Electronic Theses and Dissertations

Expertise in physics has been traditionally studied in cognitive science, where physics expertise is understood through the difference between novice and expert problem solving skills. The cognitive perspective of physics experts only create a partial model of physics expertise and does not take into account the development of physics experts in the natural context of research. This dissertation takes a social and cultural perspective of learning through apprenticeship to model the development of physics expertise of physics graduate students in a research group. I use a qualitative methodological approach of an ethnographic case study to observe and video record the …

Dysregulated Left Inferior Parietal Activity In Schizophrenia And Depression: Functional Connectivity And Characterization, Veronika I. Müller, Edna C. Cieslik, Angela Laird, Peter T. Fox, Simon B. Eickhoff

Department of Physics

The inferior parietal cortex (IPC) is a heterogeneous region that is known to be involved in a multitude of diverse different tasks and processes, though its contribution to these often-complex functions is yet poorly understood. In a previous study we demonstrated that patients with depression failed to deactivate the left IPC during processing of congruent audiovisual information. We now found the same dysregulation (same region and condition) in schizophrenia. By using task-independent (resting state) and task-dependent meta-analytic connectivity modeling (MACM) analyses we aimed at characterizing this particular region with regard to its connectivity and function. Across both approaches, results revealed …

Segregation Of The Human Medial Prefrontal Cortex In Social Cognition, Danilo Bzdok, Robert Langner, Leonhard Schilbach, Denis A. Engemann, Angela Laird, Peter T. Fox, Simon Eickhoff

Department of Physics

While the human medial prefrontal cortex (mPFC) is widely believed to be a key node of neural networks relevant for socio-emotional processing, its functional subspecialization is still poorly understood. We thus revisited the often assumed differentiation of the mPFC in social cognition along its ventral-dorsal axis. Our neuroinformatic analysis was based on a neuroimaging meta-analysis of perspective-taking that yielded two separate clusters in the ventral and dorsal mPFC, respectively. We determined each seed region's brain-wide interaction pattern by two complementary measures of functional connectivity: co-activation across a wide range of neuroimaging studies archived in the BrainMap database and correlated signal …

Mechanical And Electrical Properties Of Single-Walled Carbon Nanotubes Synthesized By Chemical Vapor Deposition, Yuehai Yang

FIU Electronic Theses and Dissertations

Despite the tremendous application potentials of carbon nanotubes (CNTs) proposed by researchers in the last two decades, efficient experimental techniques and methods are still in need for controllable production of CNTs in large scale, and for conclusive characterizations of their properties in order to apply CNTs in high accuracy engineering. In this dissertation, horizontally well-aligned high quality single-walled carbon nanotubes (SWCNTs) have been successfully synthesized on St-cut quartz substrate by chemical vapor deposition (CVD). Effective radial moduli (E_radial) of these straight SWCNTs have been measured by using well-calibrated tapping mode and contact mode atomic force microscopy (AFM). It …

Pressure Induced Structural Changes And Gas Diffusion Pathways In Monomeric Fluorescent Proteins, Yuba R. Bhandari

FIU Electronic Theses and Dissertations

Fluorescent proteins (FPs) are extremely valuable biochemical markers which have found a wide range of applications in cellular and molecular biology research. The monomeric variants of red fluorescent proteins (RFPs), known as mFruits, have been especially valuable for in vivo applications in mammalian cell imaging. Fluorescent proteins consist of a chromophore caged in the beta-barrel protein scaffold. The photophysical properties of an FP is determined by its chromophore structure and its interactions with the protein barrel.

Application of hydrostatic pressure on FPs results in the modification of the chromophore environment which allows a systematic study of the role of the …

Coherent Manipulation Of Quantum States In A Coupled Cavity-Atom System, Yanhua Wang, Jinyin Wan, Bichen Zhou, Jiepeng Zhang, Yifu Zhu

Department of Physics

We study atomic coherence and interference in four-level atoms confined in an optical cavity and explores the interplay between cavity QED and electromagnetically induced transparency (EIT). The destructive interference can be induced in the coupled cavityatom system with a free-space control laser tuned to the normal mode resonance and leads to suppression of the normal mode excitation. Then by adding a pump laser coupled to the four-level atoms from free space, the control-laser induced destructive interference can be reversed and the normal mode excitation is restored. When the free-space control laser is tuned to the atomic resonance and forms a …

Ica Model Order Selection Of Task Co-Activation Networks, Kimberly L. Ray, D. Reese Mckay, Peter M. Fox, Michael C. Riedel, Angela M. Uecker, Christian F. Beckman, Stephen M. Smith, Peter T. Fox, Angela Laird

Department of Physics

Independent component analysis (ICA) has become a widely used method for extracting functional networks in the brain during rest and task. Historically, preferred ICA dimensionality has widely varied within the neuroimaging community, but typically varies between 20 and 100 components. This can be problematic when comparing results across multiple studies because of the impact ICA dimensionality has on the topology of its resultant components. Recent studies have demonstrated that ICA can be applied to peak activation coordinates archived in a large neuroimaging database (i.e., BrainMap Database) to yield whole-brain task-based co-activation networks. A strength of applying ICA to BrainMap data …

From Vision To Change: Educational Initiatives And Research At The Intersection Of Physics And Biology, Eric Brewe, Nancy Pelaez, Todd J. Cooke

Department of Physics

In this editorial we link the articles published in this Special Issue with the framework from Vision and Change and summarize findings from the editorial process of assembling the Special Issue.

Toward University Modeling Instruction—Biology: Adapting Curricular Frameworks From Physics To Biology, Seth Manthey, Eric Brewe

Department of Physics

University Modeling Instruction (UMI) is an approach to curriculum and pedagogy that focuses instruction on engaging students in building, validating, and deploying scientific models. Modeling Instruction has been successfully implemented in both high school and university physics courses. Studies within the physics education research (PER) community have identified UMI’s positive impacts on learning gains, equity, attitudinal shifts, and self-efficacy. While the success of this pedagogical approach has been recognized within the physics community, the use of models and modeling practices is still being developed for biology. Drawing from the existing research on UMI in physics, we describe the theoretical foundations …