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open access

Terrestrial herpetofauna of Limnos and Agios Efstratios (Northern Aegean, Greece), including new species records for Malpolon insignitus (Geoffroy Saint-Hilaire, 1827) and Pelobates syriacus Boettger, 1889

Description: This article presents herpetofaunal observations from Limnos and Agios Efstratios, two Asia Minor continental shelf islands in the Aegean Sea. Comprehensive surveys over 88 days in total on Limnos, over a period of nine years, consisted mainly of visual encounter surveys and road cruised observations, revealed the presence of three species of amphibians and twelve species of reptiles, including two new species records for the island (Malpolon insignitus and Pelobates syriacus). The results of t… more
Date: October 25, 2016
Creator: Strachinis, Ilias & Roussos, Stephanos Antonios
Partner: UNT College of Arts and Sciences
open access

The Impact of Mental Aerobics Training on Older Adults

Description: This article investigates the impact of mental aerobics on older adults. Findings support the conclusion that MA can be an effective intervention in improving older adults’ affectivity, everyday task self-efficacy, and self-rated health.
Date: May 1, 2015
Creator: Hayslip, Bert; Paggi, Kay & Caballero, Daniela
Partner: UNT College of Arts and Sciences
open access

An Exploratory Flow Reactor Study of Hydrogen Sulfide Oxidation at 30–100 Bar

Description: Article exploring experiments on hydrogen sulfide oxidation that were conducted in Oâ‚‚/Nâ‚‚ at high pressure (30 and 100 bar) under oxidizing and stoichiometric conditions.
Date: November 9, 2016
Creator: Song, Yu; Hashemi, Hamid; Christensen, Jakob Munkholt; Zou, Chun; Haynes, Brian S.; Marshall, Paul et al.
Partner: UNT College of Arts and Sciences
open access

Experimental and Kinetic Modeling Study of Acetylene Oxidation at High Pressure

Description: Article describing a detailed chemical kinetic model for oxidation of acetylene at intermediate temperatures and high pressure that was developed and evaluated experimentally.
Date: August 29, 2016
Creator: Lopez, Jorge Gimenez; Rasmussen, Christian Lund; Hashemi, Hamid; Alzueta, MarĂ­a U.; Gao, Yide; Marshall, Paul et al.
Partner: UNT College of Arts and Sciences
open access

Confinement of antiprotons in the electrostatic space charge of positrons in a model of the ALPHA antihydrogen trap

Description: This article details the equilibrium of a positron plasma in a model of the ALPHA apparatus that is computed using a finite-difference method. The positron plasma in the model extends to axial magnetic mirrors in absence of an octupole field. Formation of a three-dimensional electrostatic potential well is found to occur self-consistently. Well depths under various conditions are evaluated. Also, the equilibrium with an antiproton plasma confined in the potential well is computed.
Date: March 17, 2016
Creator: Lane, Ryan A. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Artificially Structured Boundary for a high purity ion trap or ion source

Description: This article proposes a plasma enclosed by an Artificially Structured Boundary (ASB) as an alternative to existing ion source assemblies. In accelerator applications, many ion sources can have a limited lifetime or frequent service intervals due to sputtering and eventual degradation of the ion source assembly. Ions are accelerated towards the exit canal of positive ion sources, whereas, due to the biasing scheme, electrons or negative ions are accelerated towards the back of the ion source ass… more
Date: August 1, 2014
Creator: Pacheco, J. L.; Ordonez, Carlos A. & Weathers, Duncan L.
Partner: UNT College of Arts and Sciences
open access

Simulation Of An Antihydrogen Gravity Experiment Utilizing Multiple Apertures

Description: The article presents an analytical model and a Monte Carlo simulation of an antihydrogen gravity experiment that would employ multiple apertures. The model was developed with the primary goal of reducing the experimental run time necessary to determine the direction of free fall acceleration for antimatter in the gravitational field of the Earth. The experiment would confine cryogenic antihydrogen plasma for producing antihydrogen (e.g., by three-body recombination).
Date: April 19, 2013
Creator: Hedlof, R. M. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Electrostatic storage ring with focusing provided by the space charge of an electron plasma

Description: Article describes an electronic storage ring that employs the space charge of an electron plasma for focusing. An advantage of the present concept is that slow ions, or even a stationary ion plasma, can be confined. The concept employs an artificially structured boundary, which is defined at present as one that produces a spatially periodic static field such that the spatial period and range of the field are much smaller than the dimensions of a plasma or charged-particle beam that is confined … more
Date: April 19, 2013
Creator: Pacheco, J. L.; Ordonez, Carlos A. & Weathers, Duncan L.
Partner: UNT College of Arts and Sciences
open access

Accelerator-based fusion with a low temperature target

Description: This article reports a study of a cold target with a high Fermi energy in light of recent research that points to a new phase of hydrogen, which is hypothesized to be related to metallic hydrogen. It has been shown that if the energy transfer between injected ions and target electrons is sufficiently small, net energy gain can be achieved. As such, the target is considered to be composed of nuclei and delocalized electrons.
Date: April 19, 2013
Creator: Phillips, R. E. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Classical trajectory Monte Carlo code for simulating ion beam focusing or defocusing with magnetic elements modeled as current loops or current lines

Description: Article describes a computational tool that can be used for designing magnetic focusing or defocusing systems. A fully three-dimensional classical trajectory Monte Carlo simulation has been developed.
Date: April 19, 2013
Creator: Lane, Ryan A. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Dual levitated coils for antihydrogen production

Description: Article on theoretical and experimental efforts to use dual levitated coils to confine relatively large, cold, dense non-drifting recombining antihydrogen plasmas. The theoretical effort includes the development of a classical trajectory Monte Carlo simulation of confinement. The experimental effort includes levitation of a NdFeB permanent ring magnet, which produces a magnetic field that is qualitatively similar to the field that would be produced by the two coaxial superconducting magnetic co… more
Date: April 19, 2013
Creator: Wofford, Joshua D. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Antihydrogen Synthesis Via Magnetobound States of Protonium Within Proton-Positron-Antiproton Plasmas

Description: Article studies the possibility that antihydrogen can be synthesized via three body recombination involving magnetobound protonium through classical trajectory simulation. It has been previously reported that proton antiproton collisions can result in a correlated drift of the particles perpendicular to a magnetic field. While the two particles are in their correlated drift, they are referred to as a magnetobound protonium system. Possible three body recombination resulting in bound state anti… more
Date: July 2016
Creator: Hermosillo, M. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Effect of a finite antiproton mass on antihydrogen synthesis via magnetobound positronium within electron-positron-antiproton plasmas

Description: This article describes a study that was conducted to determine what would happen if a magnetobound positronium system encountered a finite-mass antiproton. The simulation incorporates a strong magnetic field (1 T) similar to that found within Penning traps. The simulation shows that with a finite-mass antiproton, the electron will be ejected from the system, and the positron is captured into a bound state with an antiproton thereby synthesizing antihydrogen.
Date: July 2016
Creator: Thornton, E. A. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Magnetobound positronium and protonium

Description: This article investigates the formation of magnetobound positronium and protonium via classical trajectory simulations of binary point charge interactions in an external magnetic field. The results of computer simulations of the fully three-dimensional trajectories of classical and non-relativistic point charges with the same mass, equal charge magnitude, and opposite sign are reported. The simulations show the formation of magnetobound positronium and protonium. The results yield formation cro… more
Date: August 27, 2014
Creator: Correa, J. R. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Phase space of positron trajectories exiting a charged particle source through a magnetic field point cusp

Description: This article presents a configuration of magnetic fields using properties of cylindrically symmetric permanent magnets as a candidate to produce a high purity charged particle source or trap. Cylindrically symmetric hollow permanent magnets produce magnetic field point cusps on the axis of symmetry. A magnetic field point cusp reflects all particles that lie outside a narrow region of phase space, a region dependent on particle kinetic energies and on the magnetic field intensity.
Date: August 1, 2014
Creator: Kiester, A. S.; Pacheco, J. L.; Ordonez, Carlos A. & Weathers, Duncan L.
Partner: UNT College of Arts and Sciences
open access

Giant cross-magnetic-field steps due to binary collisions between pair particles

Description: Article explores giant cross-magnetic-field steps which occur as a result of positron-electron collisions. Within a constant magnetic field (e.g., 1 T), a collision between a positron and an electron can result in a correlated drift across the magnetic field for a continuous range of impact parameters. Within this range, drift distances orders of magnitude larger than that associated with like-charge collisions were observed by computer simulation.
Date: March 5, 2015
Creator: Aguirre, F. F. & Ordonez, Carlos A.
Partner: UNT College of Arts and Sciences
open access

Explicitly teaching five technical genres to English first-language adults in a multi-major technical writing course

Description: In this article, the author reports the effects of explicitly teaching five technical genres to English first-language students enrolled in a multi-major technical writing course. Previous experimental research has demonstrated the efficacy of explicitly teaching academic writing to English first-language adults, but no comparable study on technical writing exists.
Date: 2014
Creator: Boettger, Ryan K.
Partner: UNT College of Arts and Sciences
open access

Measurements and Theoretical Predictions of Charge Exchange Cross Sections and Emission Spectra for O6+ with H2O, CO, CO2, CH4, N2, NO, N2O and Ar

Description: Article reports absolute CE cross sections for up to three exchanges of the O6+ ion with electrons from the comet/planetary gases H2O, CO, CO2, CH4, N2, NO, N2O and Ar.
Date: 2015
Creator: Machacek, J. R.; Mahapatra, Durga P.; Schultz, David R.; Ralchenko, Yu; Moradmand, A.; El Ghazaly, M. O. A. et al.
Partner: UNT College of Arts and Sciences
open access

A New Way to Understand and Address Women’s Health in the Context of Complex Systems: Self-organizing Criticality

Description: Article proposes applying concepts from nonlinear science developed and employed by physicists, economists, and meteorologists to women's health issues.
Date: January 1, 2016
Creator: Mancuso, Peggy; Liu, Fuqin; Restrepo, Elizabeth; Hamilton, Patricia; Grigolini, Paolo & Zou, Lin
Partner: UNT College of Arts and Sciences
open access

Evidence for the Involvement of Electrical, Calcium and ROS Signaling in the Systemic Regulation of Non-Photochemical Quenching and Photosynthesis

Description: Article presents study in which pulse amplitude-modulated Chl fluorescence imaging and surface electrical potential measurements accompanied by pharmacological treatments were employed to study stimuli-induced electrical signals in leaves from a broad range of plant species and in Arabidopsis thaliana mutants.
Date: February 10, 2017
Creator: Białasek, Maciej; Górecka, Magdalena; Mittler, Ron & Karpiński, Stanisław
Partner: UNT College of Arts and Sciences
open access

EMOTION-III Model: A Theoretical Framework for Social Empathic Emotions in Autonomous Control Systems

Description: In this article, a theoretical model of social empathic emotion is derived based on the principles of survival by extending the maximization of self-gains to include others as an extended-self. This extended-self model of optimization for survival provides the computational mechanisms in the optimization process to maximize self-gains without minimizing the gains (or maximizing losses) for the other individuals. Thus, it can resolve conflicts in a competitive environment, and change the social … more
Date: July 29, 2016
Creator: Tam, Nicoladie D.
Partner: UNT College of Arts and Sciences
open access

Space-charge-based electrostatic plasma confinement involving relaxed plasma species

Description: In this article, a numerical study is reported on the equilibrium properties of a surface-emitted or edge-confined non-drifting plasma. A self-consistent finite-differences evaluation of the electrostatic potential is carried out for a non-neutral plasma that follows a Boltzmann density distribution.
Date: October 23, 2012
Creator: Pacheco, J. L.; Ordonez, Carlos A. & Weathers, Duncan L.
Partner: UNT College of Arts and Sciences
open access

Targeting the PI3K/Akt signaling pathway in gastric carcinoma: A reality for personalized medicine?

Description: Article reviews the common dysregulation of phosphatidylinositol-3 kinases (PI3K)/Akt/mTOR pathway in gastric cancer (GC) and the various types of single or dual pathway inhibitors under development that might have a superior role in GC treatment.
Date: October 26, 2015
Creator: Singh, Shikha Satendra; Yap, Wei Ney; Arfuso, Frank; Kar, Shreya; Wang, Chao; Cai, Wanpei et al.
Partner: UNT College of Arts and Sciences
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