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8,858 full-text articles. Page 34 of 309.

Single Domain Soft Ferromagnetic Ferrofluid Suitable For Intratumoural Magnetic Hyperthermia, Karthickraja Duraisamy, Muthu Devaraj, Ajithkumar Gangadharan, Karen S. Martirosyan, Niroj Kumar Sahu, Prasath Manogaran, Girija Easwaradas Kreedapathy 2024 The University of Texas Rio Grande Valley

Single Domain Soft Ferromagnetic Ferrofluid Suitable For Intratumoural Magnetic Hyperthermia, Karthickraja Duraisamy, Muthu Devaraj, Ajithkumar Gangadharan, Karen S. Martirosyan, Niroj Kumar Sahu, Prasath Manogaran, Girija Easwaradas Kreedapathy

Physics & Astronomy Faculty Publications

Magnetic hyperthermia is an effective modality for treating cancerous cells selectively at the intracellular level via proper administration, surface tagging and appropriate choice of magnetic nanoparticle. Also, achieving the therapeutic temperature with as much low concentration of nanoparticles, as possible, is desirable. Recently, ferromagnetic nanoparticles or ferrofluid are gaining attention as effective magnetic hyperthermia agents due to their enhanced heating potential under in vivo conditions. In the present work, we have fabricated citrate capped cobalt ferrite ferrofluid via a simple two-step process and investigated the physicochemical, magnetic and induction heating performance. The average size of the synthesized nanoparticle …


Strongly Magnetized Accretion In Two Ultracompact Binary Systems, Thomas J. Maccarone, Thomas Kupfer, Edgar Najera Casarrubias, Liliana E. Rivera Sandoval, Aarran W. Shaw, Christoper T. Britt, Jan van Roestel, David R. Zurek 2024 The University of Texas Rio Grande Valley

Strongly Magnetized Accretion In Two Ultracompact Binary Systems, Thomas J. Maccarone, Thomas Kupfer, Edgar Najera Casarrubias, Liliana E. Rivera Sandoval, Aarran W. Shaw, Christoper T. Britt, Jan Van Roestel, David R. Zurek

Physics & Astronomy Faculty Publications

We present the discoveries of two of AM CVn systems, Gaia14aae and SDSS J080449.49+161624.8, which show X-ray pulsations at their orbital periods, indicative of magnetically collimated accretion. Both also show indications of higher rates of mass transfer relative to the expectations from binary evolution driven purely by gravitational radiation, based on existing optical data for Gaia14aae, which show a hotter white dwarf temperature than expected from standard evolutionary models, and X-ray data for SDSS J080449.49+161624.8 which show a luminosity 10−100 times higher than those for other AM CVn at similar orbital periods. The higher mass transfer rates could be driven …


Powerful Radio Sources In The Southern Sky. Iii. First Results Of The Optical Spectroscopic Campaign, A. García-Pérez, H. A. Peña-Herazo, A. Jimenez-Gallardo, V. Chavushyan, F. Massaro, S. V. White, A. Capetti, B. Balmaverde, W. R. Forman, Juan P. Madrid 2024 The University of Texas Rio Grande Valley

Powerful Radio Sources In The Southern Sky. Iii. First Results Of The Optical Spectroscopic Campaign, A. García-Pérez, H. A. Peña-Herazo, A. Jimenez-Gallardo, V. Chavushyan, F. Massaro, S. V. White, A. Capetti, B. Balmaverde, W. R. Forman, Juan P. Madrid

Physics & Astronomy Faculty Publications

We recently built the G4Jy-3CRE catalog of extragalactic radio sources. This catalog lists 264 powerful radio sources selected with similar criteria to those of the revised Third Cambridge Catalog, but visible from the Southern Hemisphere. A literature search revealed that 119 sources in the G4Jy-3CRE catalog (i.e., 45%) lack a firm spectroscopic redshift measurement. Here, we present a campaign aimed at acquiring optical spectra of G4Jy-3CRE sources and measuring their redshifts. We used single-slit observations obtained with the Víctor Blanco Telescope, the New Technology Telescope, the Southern Astrophysical Research Telescope, and the 2.1 m telescope of the Observatorio Astronómico Nacional …


Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton 2024 The University of Texas Rio Grande Valley

Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton

Physics & Astronomy Faculty Publications

No abstract provided.


Roaring To Softly Whispering: X-Ray Emission After ∼3.7 Yr At The Location Of The Transient At2018cow And Implications For Accretion-Powered Scenarios, Giulia Migliori, R. Margutti, B. D. Metzger, R. Chornock, C. Vignali, D. Brethauer, Liliana E. Rivera Sandoval, J. S. Bright, T. Laskar, D. Milisavljevic 2024 The University of Texas Rio Grande Valley

Roaring To Softly Whispering: X-Ray Emission After ∼3.7 Yr At The Location Of The Transient At2018cow And Implications For Accretion-Powered Scenarios, Giulia Migliori, R. Margutti, B. D. Metzger, R. Chornock, C. Vignali, D. Brethauer, Liliana E. Rivera Sandoval, J. S. Bright, T. Laskar, D. Milisavljevic

Physics & Astronomy Faculty Publications

We present the first deep X-ray observations of luminous fast blue optical transient (LFBOT) AT 2018cow at ∼3.7 yr since discovery, together with the reanalysis of the observation at δt ∼ 220 days. X-ray emission is significantly detected at a location consistent with AT 2018cow. The very soft X-ray spectrum and sustained luminosity are distinct from the spectral and temporal behavior of the LFBOT in the first ∼100 days and would possibly signal the emergence of a new emission component, although a robust association with AT 2018cow can only be claimed at δt ∼ 220 days, while at …


Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob McCraw, Haoyuan Chen, Zhe Qiang 2024 The University of Texas Rio Grande Valley

Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob Mccraw, Haoyuan Chen, Zhe Qiang

Physics & Astronomy Faculty Publications

Undergraduate research experiences are an instrumental component of student development, increasing conceptual understanding, promoting inquiry-based learning, and guiding potential career aspirations. Moving one step further, as research continues to become more interdisciplinary, there exists potential to accelerate student growth by granting additional perspectives through collaborative research. This study demonstrates the utilization of a model collaborative research project, specifically investigating the development of sorbent technologies for efficient CO2 capture, which is an important research area for improving environmental sustainability. A model CO2 sorbent system of heteroatom-doped porous carbon is utilized to enable students to gain knowledge of adsorption processes, through combined …


Thermal Phonon Fluctuations And Stability Of The Magnetic Dual Chiral Density Wave Phase In Dense Qcd, Efrain J. Ferrer, William Gyory, Vivian de la Incera 2024 The University of Texas Rio Grande Valley

Thermal Phonon Fluctuations And Stability Of The Magnetic Dual Chiral Density Wave Phase In Dense Qcd, Efrain J. Ferrer, William Gyory, Vivian De La Incera

Physics & Astronomy Faculty Publications

We study the stability against thermal phonon fluctuations of the magnetic dual chiral density wave (MDCDW) phase, an inhomogeneous phase arising in cold, dense QCD in a magnetic field. Following a recent study that demonstrated the absence of the Landau-Peierls (LP) instability from this phase, we calculate the (threshold) temperature at which the phonon fluctuations wash out the long-range order over a range of magnetic fields and densities relevant to astrophysical applications. Using a high-order Ginzburg-Landau expansion, we find that the threshold temperature is very near the critical temperature for fields of order 10 18     G and still a sizable …


Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob McCraw, Haoyuan Chen, Zhe Qiang 2024 The University of Texas Rio Grande Valley

Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob Mccraw, Haoyuan Chen, Zhe Qiang

Physics & Astronomy Faculty Publications

Undergraduate research experiences are an instrumental component of student development, increasing conceptual understanding, promoting inquiry-based learning, and guiding potential career aspirations. Moving one step further, as research continues to become more interdisciplinary, there exists potential to accelerate student growth by granting additional perspectives through collaborative research. This study demonstrates the utilization of a model collaborative research project, specifically investigating the development of sorbent technologies for efficient CO2 capture, which is an important research area for improving environmental sustainability. A model CO2 sorbent system of heteroatom-doped porous carbon is utilized to enable students to gain knowledge of adsorption processes, through combined …


Observed Epochal Variations In X-Ray Lines From The O Supergiant Ζ Puppis Do Not Require Substantial Changes In The Wind Mass Flux, Sean J. Gunderson, Kenneth G. Gayley, David P. Huenemoerder, Pragati Pradhan, Nathan A. Miller 2024 Embry-Riddle Aeronautical University

Observed Epochal Variations In X-Ray Lines From The O Supergiant Ζ Puppis Do Not Require Substantial Changes In The Wind Mass Flux, Sean J. Gunderson, Kenneth G. Gayley, David P. Huenemoerder, Pragati Pradhan, Nathan A. Miller

Publications

We fit the high-resolution Chandra X-ray spectra of the O supergiant ζ Puppis using the variable boundary condition (VBC) line model to test the stability of its mass-loss rate between two epochs of observation: 2000 March and 2018 July – 2019 August. At issue is whether the observed variations are induced by global changes in the cool (unshocked) wind itself or are isolated to the local pockets of hot gas (i.e. changes in the frequency and location of the shocks). Evidence in the literature favoured the possibility of a 40 per cent increase in the mass flux of the entire …


Inferring Binary Parameters With Dual-Line Gravitational Wave Detection From Tight Inspiraling Double Neutron Stars, Wen-Fan Feng, Jie-Wen Chen, Tan Liu, Yan Wang, Soumya D. Mohanty 2024 The University of Texas Rio Grande Valley

Inferring Binary Parameters With Dual-Line Gravitational Wave Detection From Tight Inspiraling Double Neutron Stars, Wen-Fan Feng, Jie-Wen Chen, Tan Liu, Yan Wang, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

Neutron star (NS) binaries can be potentially intriguing gravitational wave sources, with both high- and low-frequency radiation from the possibly aspherical individual stars and the binary orbit, respectively. The successful detection of such a dual-line source could provide fresh insights into binary geometry and NS physics. In the absence of electromagnetic observations, we develop a strategy for inferring the spin-orbit misalignment angle using the tight dual-line double NS system under the spin-orbit coupling. Based on the four-year joint detection of a typical dual-line system with the Laser Interferometer Space Antenna and Cosmic Explorer, we find that the misalignment angle and …


Anomaly Detection On Small Wind Turbine Blades Using Deep Learning Algorithms, Bridger Altice, Edwin Nazario, Mason Davis, Mohammad Shekaramiz, Todd K. Moon, Mohammad A. S. Masoum 2024 Utah State University

Anomaly Detection On Small Wind Turbine Blades Using Deep Learning Algorithms, Bridger Altice, Edwin Nazario, Mason Davis, Mohammad Shekaramiz, Todd K. Moon, Mohammad A. S. Masoum

Electrical and Computer Engineering Faculty Publications

Wind turbine blade maintenance is expensive, dangerous, time-consuming, and prone to misdiagnosis. A potential solution to aid preventative maintenance is using deep learning and drones for inspection and early fault detection. In this research, five base deep learning architectures are investigated for anomaly detection on wind turbine blades, including Xception, Resnet-50, AlexNet, and VGG-19, along with a custom convolutional neural network. For further analysis, transfer learning approaches were also proposed and developed, utilizing these architectures as the feature extraction layers. In order to investigate model performance, a new dataset containing 6000 RGB images was created, making use of indoor and …


Swarm Intelligence Methods For Extreme Mass Ratio Inspiral Search: First Application Of Particle Swarm Optimization, Xiao-Bo Zou, Soumya D. Mohanty, Hong-Gang Luo, Yu-Xiao Liu 2024 The University of Texas Rio Grande Valley

Swarm Intelligence Methods For Extreme Mass Ratio Inspiral Search: First Application Of Particle Swarm Optimization, Xiao-Bo Zou, Soumya D. Mohanty, Hong-Gang Luo, Yu-Xiao Liu

Physics & Astronomy Faculty Publications

Swarm intelligence (SI) methods are nature-inspired metaheuristics for global optimization that exploit a coordinated stochastic search strategy by a group of agents. Particle swarm optimization (PSO) is an established SI method that has been applied successfully to the optimization of rugged high-dimensional likelihood functions, a problem that represents the main bottleneck across a variety of gravitational wave (GW) data analysis challenges. We present results from the first application of PSO to one of the most difficult of these challenges, namely the search for the Extreme Mass Ratio Inspiral (EMRI) in data from future spaceborne GW detectors such as LISA, Taiji, …


Radiation From An Oscillating Dipole In The Presence Of Photon-Sector Cpt And Lorentz Violation, Joshua O'Connor, Brett Altschul 2024 University of South Carolina

Radiation From An Oscillating Dipole In The Presence Of Photon-Sector Cpt And Lorentz Violation, Joshua O'Connor, Brett Altschul

Faculty Publications

We examine one of the standard loci for studying electromagnetic wave emission - the radiation from an oscillating electric dipole - in a model in which the electromagnetic sector is modified to include novel CPT- and Lorentz-violating propagation effects involving a preferred axial vector background. We evaluate the vacuum-birefringent radiation fields, including nonperturbative terms where appropriate. In general, the energy momentum carried by the fields in this model is known to have a complicated nonperturbative structure, which cannot be captured by naive power-series expansions in the components of the preferred background vector. However, we nevertheless find that at the lowest …


There Is Life On Mars, Colin M. Johnston, Olivier B. Cohen 2024 Gettysburg College

There Is Life On Mars, Colin M. Johnston, Olivier B. Cohen

CAFE Symposium 2024

An extensive research project that involved the research of multiple major experiments and discoveries about possible life on the planet Mars. Facts, Data, conspiracies and theories have all been taken into account and provided in this project.


Extraterrestrial Life: The Possibility Of A Human-Alien Interaction, Ariana M. Piscoya 2024 Gettysburg College

Extraterrestrial Life: The Possibility Of A Human-Alien Interaction, Ariana M. Piscoya

CAFE Symposium 2024

We all have heard of at least one case where someone assured having seen a flying extraterrestrial object. There are thousands of thousands of videos we can find online that “prove” the existence of aliens. In the hypothetical case where aliens are really out there, why haven't we been able to talk to them and look at them face-to-face? A human-extraterrestrial interaction has not yet been achieved for two reasons. First, alien energy is much more powerful than that of humans, so it would require thousands of thousands of years for the human race to develop a technology able to …


Muse-Alma Haloes X: The Stellar Masses Of Gas-Rich Absorbing Galaxies, Ramona Augustin, Céline Péroux, Arjun Karki, Varsha Kulkarni, Simon Weng, A Hamanowicz, M Hayes, J C. Howk, G G. Kacprzak, A Klitsch, M A. Zwaan, A Fox, A Biggs, A Y. Fresco, S Kassin, H. Kuntschner 2024 University of South Carolina

Muse-Alma Haloes X: The Stellar Masses Of Gas-Rich Absorbing Galaxies, Ramona Augustin, Céline Péroux, Arjun Karki, Varsha Kulkarni, Simon Weng, A Hamanowicz, M Hayes, J C. Howk, G G. Kacprzak, A Klitsch, M A. Zwaan, A Fox, A Biggs, A Y. Fresco, S Kassin, H. Kuntschner

Faculty Publications

The physical processes by which gas is accreted onto galaxies, transformed into stars, and then expelled from galaxies are of paramount importance to galaxy evolution studies. Observationally constraining each of these baryonic components in the same system, however, is challenging. Furthermore, simulations indicate that the stellar mass of galaxies is a key factor influencing CGM properties. Indeed, absorption lines detected against background quasars offer the most compelling way to study the cold gas in the circumgalactic medium (CGM). The MUSE-ALMA Haloes survey is composed of quasar fields covered with VLT/MUSE observations, comprising 32 H i absorbers at 0.2 < z < 1.4 and 79 associated galaxies, with available or upcoming molecular gas measurements from ALMA. We use a dedicated 40-orbit HST …


Axion-Polaritons In Quark Stars: A Possible Solution To The Missing Pulsar Problem, Efrain J. Ferrer, Vivian de la Incera 2024 The University of Texas Rio Grande Valley

Axion-Polaritons In Quark Stars: A Possible Solution To The Missing Pulsar Problem, Efrain J. Ferrer, Vivian De La Incera

Physics & Astronomy Faculty Publications

This paper proposes an alternative mechanism to solve the so-called missing pulsar problem, a standing paradox between the theoretical expectations about the number of pulsars that should exist in the galaxy center of the Milky Way and their absence in the observations. The mechanism is based on the transformation of incident γ rays into hybridized modes, known as axion-polaritons, which can exist inside highly magnetized quark stars with a quark matter phase known as the magnetic dual chiral density wave phase. This phase, which is favored over several other dense matter phases candidates at densities a few times nuclear saturation …


Flavors And Frailties Of Globalization, Nikhilesh Dholakia, Deniz Atik 2024 University of Rhode Island

Flavors And Frailties Of Globalization, Nikhilesh Dholakia, Deniz Atik

Markets, Globalization & Development Review

No abstract provided.


Jwst-Tsthigh Contrast: Asymmetries, Dust Populations, And Hints Of A Collision In The Β Pictoris Disk With Nircam And Miri, Isabel Rebollido, Christopher C. Stark, Jens Kammerer, Marshall D. Perrin, Kellen Lawson, Laurent Pueyo, Christine Chen, Dean Hines, Julien H. Girard, Kadin Worthen, Carl Ingerbretsen, Sarah Betti, Mark Clampin, David Golimowski, Kielan Hoch, Nikole K. Lewis, Cicero X. Lu, Roeland P. van der Marel, Emily Rickman, Sara Seager, Rémi Soummer, Jeff A. Valenti, Kimberly Ward-Duong, C. Matt Mountain 2024 CSIC-INTA - Centro de Astrobiología (CAB)

Jwst-Tsthigh Contrast: Asymmetries, Dust Populations, And Hints Of A Collision In The Β Pictoris Disk With Nircam And Miri, Isabel Rebollido, Christopher C. Stark, Jens Kammerer, Marshall D. Perrin, Kellen Lawson, Laurent Pueyo, Christine Chen, Dean Hines, Julien H. Girard, Kadin Worthen, Carl Ingerbretsen, Sarah Betti, Mark Clampin, David Golimowski, Kielan Hoch, Nikole K. Lewis, Cicero X. Lu, Roeland P. Van Der Marel, Emily Rickman, Sara Seager, Rémi Soummer, Jeff A. Valenti, Kimberly Ward-Duong, C. Matt Mountain

Astronomy: Faculty Publications

We present the first JWST Mid-Infrared Instrument (MIRI) and Near Infrared Camera (NIRCam) observations of the prominent debris disk around β Pictoris. Coronagraphic observations in eight filters spanning from 1.8 to 23 μm provide an unprecedentedly clear view of the disk at these wavelengths. The objectives of the observing program were to investigate the dust composition and distribution and to investigate the presence of planets in the system. In this paper, we focus on the disk components, providing surface brightness measurements for all images and a detailed investigation of the asymmetries observed. A companion paper by Kammerer et al. will …


Vlti/Gravity Provides Evidence The Young, Substellar Companion Hd 136164 Ab Formed Like A “Failed Star”, William O. Balmer, L. Pueyo, S. Lacour, J. J. Wang, T. Stolker, J. Kammerer, N. Pourré, M. Nowak, E. Rickman, S. Blunt, A. Sivaramakrishnan, D. Sing, K. Wagner, G. D. Marleau, A. M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, M. S. Bordoni, G. Bourdarot, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, et al, Kimberly Ward-Duong 2024 Johns Hopkins University

Vlti/Gravity Provides Evidence The Young, Substellar Companion Hd 136164 Ab Formed Like A “Failed Star”, William O. Balmer, L. Pueyo, S. Lacour, J. J. Wang, T. Stolker, J. Kammerer, N. Pourré, M. Nowak, E. Rickman, S. Blunt, A. Sivaramakrishnan, D. Sing, K. Wagner, G. D. Marleau, A. M. Lagrange, R. Abuter, A. Amorim, R. Asensio-Torres, J. P. Berger, H. Beust, A. Boccaletti, A. Bohn, M. Bonnefoy, H. Bonnet, M. S. Bordoni, G. Bourdarot, W. Brandner, F. Cantalloube, P. Caselli, B. Charnay, Et Al, Kimberly Ward-Duong

Astronomy: Faculty Publications

Young, low-mass brown dwarfs orbiting early-type stars, with low mass ratios (q ≲ 0.01), appear to be intrinsically rare and present a formation dilemma: could a handful of these objects be the highest-mass outcomes of “planetary” formation channels (bottom up within a protoplanetary disk), or are they more representative of the lowest-mass “failed binaries” (formed via disk fragmentation or core fragmentation)? Additionally, their orbits can yield model-independent dynamical masses, and when paired with wide wavelength coverage and accurate system age estimates, can constrain evolutionary models in a regime where the models have a wide dispersion depending on the initial conditions. …


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