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2020

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Full-Text Articles in Physics

Published Research Documents In Nuclear And High Energy Physics From 1996-2019: A Bibliometric Analysis Of Leading Countries In Comparison With India, Ishwar Dutt Sharma Dr Dec 2020

Published Research Documents In Nuclear And High Energy Physics From 1996-2019: A Bibliometric Analysis Of Leading Countries In Comparison With India, Ishwar Dutt Sharma Dr

Library Philosophy and Practice (e-journal)

A bibliometric analysis of scientific research production of the top five most productive countries in comparison with India in nuclear and high energy physics is presented during the period 1996-2019 using Scopus-linked SCImago electronic database. To validate the present study, some selected bibliometric indicators such as published documents, their citations and citations per document has been studied. In total, 769180 research documents were published worldwide in journal, conference proceedings and in book series. United States (16.47%), Germany(8.64%), Japan (6.65%), China (6.41%) and Russian Federation (5.89%) were the top most productive countries rankwise, whereas India ranked 10th with 21157 research …


Composite Network Of Actin And Microtubule Filaments, Self-Organization And Steady-State Dynamics, Leila Farhadi Dec 2020

Composite Network Of Actin And Microtubule Filaments, Self-Organization And Steady-State Dynamics, Leila Farhadi

Doctoral Dissertations

Actin and microtubule filaments, with their auxiliary proteins, enable the cytoskeleton to perform vital processes in the cell by tuning the organizational, mechanical properties and dynamics of the network. Despite their critical importance and interactions in cells, we are only beginning to uncover information about the composite network. Here, I use florescence microscopy to explore the role of filaments characteristics, interactions and activities in the self-organization and steady-state dynamics of the composite network of filaments. First, I discuss active self-organization of semiflexible actin and rigid microtubule filaments in the 2D composite network while myosin II and kinesin-1 motor proteins propel …


Distortion-Controlled Isotropic Swelling And Self-Assembly Of Triply-Periodic Minimal Surfaces, Carlos M. Duque Dec 2020

Distortion-Controlled Isotropic Swelling And Self-Assembly Of Triply-Periodic Minimal Surfaces, Carlos M. Duque

Doctoral Dissertations

In the first part of this thesis, I propose a method that allows us to construct optimal swelling patterns that are compatible with experimental constraints. This is done using a greedy algorithm that systematically increases the perimeter of the target surface with the help of minimum length cuts. This reduces the areal distortion that comes from the changing Gaussian curvature of the sheet. The results of our greedy cutting algorithm are tested on surfaces of constant and varying Gaussian curvature, and are additionally validated with finite thickness simulations using a modified Seung-Nelson model. In the second part of the thesis, …


Searching For New Physics At Colliders And From Precision Measurements, Yong Du Dec 2020

Searching For New Physics At Colliders And From Precision Measurements, Yong Du

Doctoral Dissertations

Beyond the great triumph of the Standard Model of particle physics, several fundamental questions remain unknown with the framework of the Standard Model. Among them are the non-zero neutrino masses, the dark matter and the baryon asymmetry of the Universe. Answers to these questions require new physics beyond the Standard Model and searching for the new physics beyond the SM has been a major task for modern particle physicists. The signal of this new physics can be searched through colliders, low- and high-energy precision measurements, as well as precision cosmological observation. Here I present my work in searching for the …


Experimental Study Of Viscoelastic Fluid-Structure Interactions, Anita Anup Dey Dec 2020

Experimental Study Of Viscoelastic Fluid-Structure Interactions, Anita Anup Dey

Doctoral Dissertations

It is well known that when a flexible or flexibly-mounted structure is placed perpendicular to a Newtonian fluid flow, it can oscillate due to the shedding of vortices at high Reynolds numbers. Unlike Newtonian fluids, viscoelastic fluid flow can become unstable even at infinitesimal Reynolds numbers due to a purely elastic flow instability occurring at large Weissenberg numbers. This thesis focuses on exploring the mechanisms of viscoelastic fluid-structure interactions (VFSI) through experimental investigations on several different combinations of flexible and flexibly-mounted circular cylinders, micro and macro-scale cantilevered beams and viscoelastic fluids such as wormlike micelle solutions and polymer solutions. VFSI …


Theory And Improved Methods For Probing The Cavitation To Fracture Transition, Christopher Barney Dec 2020

Theory And Improved Methods For Probing The Cavitation To Fracture Transition, Christopher Barney

Doctoral Dissertations

A material is considered soft when its bulk modulus is significantly greater than its shear modulus. Rubbery polymers are a class of soft materials where resistance to extension is mainly entropic in nature. Polymeric soft solids differ from liquids due to the presence of a percolated network of strong bonds that resist deformation and flow on a given time scale. The incompressible nature, entropically driven elasticity, and molecular scale network structure of soft polymeric solids combine to impart unique mechanical behavior that often results in complex material responses to simple loading situations. An important example of this is cavitation in …


Filaments, Fibers, And Foliations In Frustrated Soft Materials, Daria Atkinson Dec 2020

Filaments, Fibers, And Foliations In Frustrated Soft Materials, Daria Atkinson

Doctoral Dissertations

Assemblies of one-dimensional filaments appear in a wide range of physical systems: from biopolymer bundles, columnar liquid crystals, and superconductor vortex arrays; to familiar macroscopic materials, like ropes, cables, and textiles. Interactions between the constituent filaments in such systems are most sensitive to the distance of closest approach between the central curves which approximate their configuration, subjecting these distinct assemblies to common geometric constraints. Dual to strong dependence of inter-filament interactions on changes in the distance of closest approach is their relative insensitivity to reptations, translations along the filament backbone. In this dissertation, after briefly reviewing the mechanics and …


Modeling Residence Time Distribution Of Chromatographic Perfusion Resin For Large Biopharmaceutical Molecules: A Computational Fluid Dynamic Study, Kevin Vehar Dec 2020

Modeling Residence Time Distribution Of Chromatographic Perfusion Resin For Large Biopharmaceutical Molecules: A Computational Fluid Dynamic Study, Kevin Vehar

KGI Theses and Dissertations

The need for production processes of large biotherapeutic particles, such as virus-based particles and extracellular vesicles, has risen due to increased demand in the development of vaccinations, gene therapies, and cancer treatments. Liquid chromatography plays a significant role in the purification process and is routinely used with therapeutic protein production. However, performance with larger macromolecules is often inconsistent, and parameter estimation for process development can be extremely time- and resource-intensive. This thesis aimed to utilize advances in computational fluid dynamic (CFD) modeling to generate a first-principle model of the chromatographic process while minimizing model parameter estimation's physical resource demand. Specifically, …


Thermo-Fluid Characterizations Of The Powder-Bed Fusion Additive Manufacturing Processes Using Laser And Electron Beam, M Shafiqur Rahman Dec 2020

Thermo-Fluid Characterizations Of The Powder-Bed Fusion Additive Manufacturing Processes Using Laser And Electron Beam, M Shafiqur Rahman

University of New Orleans Theses and Dissertations

The powder-bed fusion (PBF) process is a subdivision of Additive Manufacturing (AM) technology where a heat source at a controlled speed selectively fuses regions of a powder-bed material to form three-dimensional (3-D) parts. Two of the most effective PBF processes are selective laser melting (SLM) and electron beam additive manufacturing (EBAM), which can fabricate full-density metallic parts in a layer-by-layer fashion. In this study, thermal behavior and melt-pool dynamics in the PBF process are investigated by developing 3-D multiphysics-based thermo-fluid models for both SLM and EBAM, containing Ti-6Al-4V alloy as a powder-bed material. The laser and electron beams are modeled …


A Transformative Approach To Incorporating Adaptive Courseware: Strategic Implementation, Backward Design And Research-Based Teaching Practices, Tonya A. Buchan, Stanley Kruse, Jennifer Todd, Lee Tyson Dec 2020

A Transformative Approach To Incorporating Adaptive Courseware: Strategic Implementation, Backward Design And Research-Based Teaching Practices, Tonya A. Buchan, Stanley Kruse, Jennifer Todd, Lee Tyson

Current Issues in Emerging eLearning

In July 2016, Colorado State University (CSU) joined seven other land-grant institutions in the Accelerating Adoption of Adaptive Courseware grant sponsored by the Personalized Learning Consortium (PLC) of the Association of Public and Land-grant Universities (APLU). A primary objective of the grant was to scale the adoption of adaptive courseware in general education courses at each of the grant institutions. CSU targeted high-enrollment, general education courses and took a three-pronged, transformative approach to the integration of adaptive courseware. Specifically, CSU divided the courseware integration into three components: 1) strategic implementation of courseware, 2) backward course design, and 3) incorporation of …


Transitions Between Radial And Bipolar Liquid Crystal Drops In The Presence Of Novel Surfactants, Jake Shechter Dec 2020

Transitions Between Radial And Bipolar Liquid Crystal Drops In The Presence Of Novel Surfactants, Jake Shechter

Doctoral Dissertations

Liquid crystals (LCs) are a class of molecules that form a variety of configurations easily influenced by external interactions. Of particular interest are rod-like LC molecules confined to a spherical geometry, which have a competition between interfacial tension and elastic deformations. The configuration of the liquid crystal inside a droplet can be controlled using surfactants, influencing the boundary conditions, in an oil-in-water emulsion. I tested the effects of novel surfactants on the configuration of the LC droplets. These novel surfactant molecules, synthesized by collaborators, are oligomers with either a variable length hydrophobic domain or protein sensitive hydrophilic domain. I tested …


Controlled Membrane Remodeling By Nanospheres And Nanorods: Experiments Targeting The Design Principles For Membrane-Based Materials, Sarah Zuraw-Weston Dec 2020

Controlled Membrane Remodeling By Nanospheres And Nanorods: Experiments Targeting The Design Principles For Membrane-Based Materials, Sarah Zuraw-Weston

Doctoral Dissertations

In this thesis we explore two experimental systems probing the interactions of nanoparticles with lipid bilayer membranes. Inspired by the ability of cell membranes to alter their shape in response to bound particles, we report two experimental studies: one of nanospheres the other of long, slender nano-rods binding to lipid bilayer vesicles and altering the membrane shape. Our work illuminates the role of particle geometry, particle concentration, adhesion strength and membrane tension in how membrane morphology is determined. We combine giant unilamellar vesicles with oppositely charged nanoparticles, carefully tuning adhesion strength, membrane tension and particle concentration. In the case of …


Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace Dec 2020

Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace

Electronic Theses and Dissertations

Influenza virus, colloquially known as the flu, is an acute respiratory disease that infects several millions of individuals each year in the U.S. and kills tens of thousands of those infected. Yearly viral vaccines are widely available, however, due to the virus’s high mutation rate, their efficacy varies greatly. Due to the variability in vaccine efficiency against seasonal influenza, and the potential for even more pathogenic versions of influenza to emerge at any time, there is a high demand for a universal treatment option.

Influenza virus hijacks a variety of host cell components in order to replicate. The glycoprotein hemagglutinin …


Retention Of Rising Oil Droplets In Density Stratification, Tracy L. Mandel, De Zhen Zhou, Lindsay Waldrop, Maxime Theillard, Dustin Kleckner, Shilpa Khatri Dec 2020

Retention Of Rising Oil Droplets In Density Stratification, Tracy L. Mandel, De Zhen Zhou, Lindsay Waldrop, Maxime Theillard, Dustin Kleckner, Shilpa Khatri

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In this study, we present results from experiments on the retention of single oil droplets rising through a two-layer density stratification, with the goal of quantifying and parametrizing the impact of stratification on timescales that describe the delay in rising. These experiments confirm the significant slowdown observed in past literature of settling and rising particles and droplets in stratification, and these are the first experiments to study single liquid droplets as opposed to solid particles or bubbles. By tracking the motion of the droplets as they rise through a stratified fluid, we identify two new timescales which quantitatively describe this …


Toward Non-Invasive Measurement Of Atmospheric Temperature Using Vibro-Rotational Raman Spectra Of Diatomic Gases, Tyler Capek, Jacek Borysow, Claudio Mazzoleni, Massimo Moraldi Dec 2020

Toward Non-Invasive Measurement Of Atmospheric Temperature Using Vibro-Rotational Raman Spectra Of Diatomic Gases, Tyler Capek, Jacek Borysow, Claudio Mazzoleni, Massimo Moraldi

Michigan Tech Publications

We demonstrate precise determination of atmospheric temperature using vibro-rotational Raman (VRR) spectra of molecular nitrogen and oxygen in the range of 292–293 K. We used a continuous wave fiber laser operating at 10 W near 532 nm as an excitation source in conjunction with a multi-pass cell. First, we show that the approximation that nitrogen and oxygen molecules behave like rigid rotors leads to erroneous derivations of temperature values from VRR spectra. Then, we account for molecular non-rigidity and compare four different methods for the determination of air temperature. Each method requires no temperature calibration. The first method involves fitting …


Fisher Formalism For Anisotropic Gravitational-Wave Background Searches With Pulsar Timing Arrays, Y. Ali-Haïmoud, Tristan L. Smith, C. M. F. Mingarelli Dec 2020

Fisher Formalism For Anisotropic Gravitational-Wave Background Searches With Pulsar Timing Arrays, Y. Ali-Haïmoud, Tristan L. Smith, C. M. F. Mingarelli

Physics & Astronomy Faculty Works

Pulsar timing arrays (PTAs) are currently the only experiments directly sensitive to gravitational waves with decade-long periods. Within the next five to ten years, PTAs are expected to detect the stochastic gravitational-wave background (SGWB) collectively sourced by inspiraling supermassive black hole binaries. It is expected that this background is mostly isotropic, and current searches focus on the monopole part of the SGWB. Looking ahead, anisotropies in the SGWB may provide a trove of additional information on both known and unknown astrophysical and cosmological sources. In this paper, we build a simple yet realistic Fisher formalism for anisotropic SGWB searches with …


Robustness Of Baryon Acoustic Oscillation Constraints For Early-Universe Modifications Of Λcdm Cosmology, J. L. Bernal, Tristan L. Smith, K. K. Boddy, M. Kamionkowski Dec 2020

Robustness Of Baryon Acoustic Oscillation Constraints For Early-Universe Modifications Of Λcdm Cosmology, J. L. Bernal, Tristan L. Smith, K. K. Boddy, M. Kamionkowski

Physics & Astronomy Faculty Works

Baryon acoustic oscillations (BAO) provide a robust standard ruler and can be used to constrain the expansion history of the Universe at low redshift. Standard BAO analyses return a model-independent measurement of the expansion rate and the comoving angular diameter distance as a function of redshift, normalized by the sound horizon at radiation drag. However, this methodology relies on anisotropic distance distortions of a fixed, precomputed template (obtained in a given fiducial cosmology) in order to fit the observations. Therefore, it may be possible that extensions to the consensus ΛCDM add contributions to the BAO feature that cannot be captured …


Eureka Moment As Divine Spark In The Light Of Direct Experience With The Spirit And Nature, Victor Christianto, Florentin Smarandache Dec 2020

Eureka Moment As Divine Spark In The Light Of Direct Experience With The Spirit And Nature, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In the ancient world, the Greeks believed that all great insights came from one of nine muses, divine sisters who brought inspiration to mere mortals. In the modern world, few people still believe in the muses, but we all still love to hear stories of sudden inspiration. Like Newton and the apple, or Archimedes and the bathtub (both another type of myth), we’re eager to hear and to share stories about flashes of insight. But what does it take to be actually creative? How to have such a flash insight? Turns out, there is real science behind "aha moments." We …


Editorial Board Dec 2020

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.


Rapid Radiological Analysis Of Building Materials, Askar Safarov, Joseph Sharonov, Ali Mukhamedov, Askarali Azimov, Akmal Safarov, Mukhammad Salimov, B Radzhabboev Dec 2020

Rapid Radiological Analysis Of Building Materials, Askar Safarov, Joseph Sharonov, Ali Mukhamedov, Askarali Azimov, Akmal Safarov, Mukhammad Salimov, B Radzhabboev

Scientific Journal of Samarkand University

Measurements of the dose-forming radionuclide concentrations such as Rа-226, Тh-232 and К-40 were carried out in samples of building materials with different ageing times. The radium equivalent activities of the samples were determined. Possible values of the correcting coefficients to the activity of Ra-226 that take into account the radioactive equilibrium were calculated. This, in turn, allows to perform rapid radiological analysis of building materials.


National Security And Climate Change, Madison Moran Dec 2020

National Security And Climate Change, Madison Moran

Physics Capstone Projects

Certain scientific subjects are often divisive or technical, which makes those topics difficult to discuss with audiences outside the scientific sphere. One way of getting around this obstacle is to cater scientific communication to different target audiences to cut through any audience biases. In order to accomplish that, a communicator needs to understand the relationship between audiences’ worldviews, and what they know, feel, and do regarding the subject at hand, and then how that relationship influences the types of media audiences trust and to which they respond positively. The following study investigates the worldviews of a military audience with respect …


Monitoring The Low Frequency Radio Transient Sky With The Long Wavelength Array, Savin Shynu Varghese Dec 2020

Monitoring The Low Frequency Radio Transient Sky With The Long Wavelength Array, Savin Shynu Varghese

Physics & Astronomy ETDs

Transient searches in radio astronomy have discovered some of the most extreme astrophysical phenomena in our universe. This has enabled us to study the physics of these explosive and dynamic sources. Most of the transient searches over the past 70 years have been at frequencies higher than 100 MHz leaving the transient sky below 100 MHz unexplored. The Long Wavelength Array (LWA) telescope offers an excellent opportunity to study the transient sky below 100 MHz with its wide field of view, high sensitivity and fast imaging at shorter timescales. This dissertation presents the transient searches carried out using the all-sky …


Large Global Variations In Measured Airborne Metal Concentrations Driven By Anthropogenic Sources, Jacob Mcneill, Randal V. Martin, Nofel Lagrosas, 35 Co-Authors Dec 2020

Large Global Variations In Measured Airborne Metal Concentrations Driven By Anthropogenic Sources, Jacob Mcneill, Randal V. Martin, Nofel Lagrosas, 35 Co-Authors

SOSE Affiliate: Manila Observatory

Globally consistent measurements of airborne metal concentrations in fine particulate matter (PM2.5) are important for understanding potential health impacts, prioritizing air pollution mitigation strategies, and enabling global chemical transport model development. PM2.5 filter samples (N ~ 800 from 19 locations) collected from a globally distributed surface particulate matter sampling network (SPARTAN) between January 2013 and April 2019 were analyzed for particulate mass and trace metals content. Metal concentrations exhibited pronounced spatial variation, primarily driven by anthropogenic activities. PM2.5 levels of lead, arsenic, chromium, and zinc were significantly enriched at some locations by factors of 100–3000 compared …


Precision Measurement Of The Ratio Β(Y(3S) → Τ + Τ) / Β( Y(3S)→ Μ+ Μ, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al. Dec 2020

Precision Measurement Of The Ratio Β(Y(3S) → Τ + Τ−) / Β( Y(3S)→ Μ+ Μ−, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al.

Faculty Publications

We report on a precision measurement of the ratio Rϒð3SÞ τμ ¼ Bðϒð3SÞ → τþτ−Þ=Bðϒð3SÞ → μþμ−Þ using data collected with the BABAR detector at the SLAC PEP-II eþe− collider. The measurement is based on a 28 fb−1 data sample collected at a center-of-mass energy of 10.355 GeV corresponding to a sample of 122 million ϒð3SÞ mesons. The ratio is measured to be Rϒð3SÞ τμ ¼ 0.966 0.008stat 0.014syst and is in agreement with the standard model prediction of 0.9948 within 2 standard deviations. The uncertainty in Rϒð3SÞ τμ is almost an order of magnitude smaller than the only previous …


The Ideal Dog, Owen Graham Dec 2020

The Ideal Dog, Owen Graham

Fall Student Research Symposium 2020

The goal of this project was to look into all of the different jobs or tasks that we as humans have dogs perform and try to pinpoint what exactly it is that makes a dog ideal for each task. After identifying desirable characteristics, I considered physical traits in order to create an ideal dog that would be able to perform the greatest number of jobs possible.


National Security & Climate Change, Madison Mortensen Dec 2020

National Security & Climate Change, Madison Mortensen

Fall Student Research Symposium 2020

Certain scientific subjects are often divisive or technical, which makes those topics difficult to discuss with audiences outside the scientific sphere. One way of getting around this obstacle is to cater scientific communication to different target audiences to cut through any audience biases. In order to accomplish that, a communicator needs to understand the relationship between audiences' worldviews, and what they know, feel, and do regarding the subject at hand, and then how that relationship influences the types of media audiences trust and to which they respond positively. The following study investigates the worldviews of a military audience with respect …


Galactic Sources In Gamma-Ray Diffuse Emission, Melissa Rasmussen Dec 2020

Galactic Sources In Gamma-Ray Diffuse Emission, Melissa Rasmussen

Fall Student Research Symposium 2020

The Fermi Large Area Telescope (LAT) has detected hundreds of Galactic gamma-ray sources, most of them pulsars. But the Galaxy contains tens of thousands of such sources which are still undetected due to their low flux, or because of conflation of the foreground with sources. Characterizing the general properties of detected sources would allow us to estimate the contribution to the diffuse Galactic emission from these undetected sources and in turn it would help the detection of new sources and even searches for dark matter. We present updates on our long-term effort to characterize the general properties of Galactic gamma-ray …


Dog-Headed: Outcast To All, Wesley Mills Dec 2020

Dog-Headed: Outcast To All, Wesley Mills

Fall Student Research Symposium 2020

Cynocephali are a group of mythological, dog-headed, humans that appear throughout various cultures. Despite the wide range of region and time period in which they are used, they consistently represent a quality of "otherness".


Modeling Reflectance Spectra Of Nanorod Arrays With Arrays Of Light Sources, Christian Lange Dec 2020

Modeling Reflectance Spectra Of Nanorod Arrays With Arrays Of Light Sources, Christian Lange

Fall Student Research Symposium 2020

It is known that carbon-nanotube forests, nanopillar arrays, and other formations of quasi-periodic nanostructures of various materials (semiconductors, semimetals, and metals) can display a very low light reflectance over a wide range of wavelengths, and that the reflectance eventually starts to rise beyond an onset wavelength. As these materials can be quite reflective in planar form, this phenomenon indicates that morphology rather than material plays a dominant role. However, a quantitative analysis of the reflectance spectra of periodic structures has yet to be established. As a first step, we use an array of light sources to model the reflection from …


Infinite Volume Reconstruction Method Qed Pion Mass Corrections On The Lattice, Michael Riberdy Dec 2020

Infinite Volume Reconstruction Method Qed Pion Mass Corrections On The Lattice, Michael Riberdy

Honors Scholar Theses

We use the Infinite Volume Reconstruction Method to calculate the charged/neutral pion mass difference. The hadronic tensor is calculated on the lattice using a QCD+QED framework, and the mass shift is calculated with exponentially-suppressed finite volume errors. In this paper we discuss the Feynman diagrams relevant to the pion mass difference and we recapitulate the advantages of the Infinite Volume Reconstruction Method. We then discuss the extrapolation to the continuum limit, and report a charged/neutral pion mass difference of 4.52 MeV, which is within 1.44% of the accepted value.