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University of Texas Rio Grande Valley

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Articles 1801 - 1830 of 2419

Full-Text Articles in Physical Sciences and Mathematics

Inference Of Snp-Gene Regulatory Networks By Integrating Gene Expressions And Genetic Perturbations, Dongchul Kim, Jiao Wang, Chunyu Liu, Jean Gao Jun 2014

Inference Of Snp-Gene Regulatory Networks By Integrating Gene Expressions And Genetic Perturbations, Dongchul Kim, Jiao Wang, Chunyu Liu, Jean Gao

Computer Science Faculty Publications and Presentations

In order to elucidate the overall relationships between gene expressions and genetic perturbations, we propose a network inference method to infer gene regulatory network where single nucleotide polymorphism (SNP) is involved as a regulator of genes. In the most of the network inferences named as SNP-gene regulatory network (SGRN) inference, pairs of SNP-gene are given by separately performing expression quantitative trait loci (eQTL) mappings. In this paper, we propose a SGRN inference method without predefined eQTL information assuming a gene is regulated by a single SNP at most. To evaluate the performance, the proposed method was applied to random data …

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Arecibo Pulsar Survey Using Alfa. Iii. Precursor Survey And Population Synthesis, J. K. Swiggum, D. R. Lorimer, M. A. Mclaughlin, S. D. Bates, D. J. Champion, S. M. Ransom, P. Lazarus, A. Brazier, J. W.T. Hessels, D. J. Nice, J. Ellis, T. R. Senty, B. Allen, N. D.R. Bhat, S. Bogdanov, F. Camilo, S. Chatterjee, J. M. Cordes, F. Crawford, J. S. Deneva, P. C.C. Freire, F. A. Jenet, C. Karako-Argaman, V. M. Kaspi, B. Knispel, K. J. Lee, J. Van Leeuwen, R. Lynch, A. G. Lyne, P. Scholz Jun 2014

Arecibo Pulsar Survey Using Alfa. Iii. Precursor Survey And Population Synthesis, J. K. Swiggum, D. R. Lorimer, M. A. Mclaughlin, S. D. Bates, D. J. Champion, S. M. Ransom, P. Lazarus, A. Brazier, J. W.T. Hessels, D. J. Nice, J. Ellis, T. R. Senty, B. Allen, N. D.R. Bhat, S. Bogdanov, F. Camilo, S. Chatterjee, J. M. Cordes, F. Crawford, J. S. Deneva, P. C.C. Freire, F. A. Jenet, C. Karako-Argaman, V. M. Kaspi, B. Knispel, K. J. Lee, J. Van Leeuwen, R. Lynch, A. G. Lyne, P. Scholz

Physics and Astronomy Faculty Publications and Presentations

The Pulsar Arecibo L-band Feed Array (PALFA) Survey uses the ALFA 7-beam receiver to search both inner and outer Galactic sectors visible from Arecibo (32° ≲ â„“ ≲ 77°and 168°≲ â„“ ≲ 214°) close to the Galactic plane (|b| ≲ 5°) for pulsars. The PALFA survey is sensitive to sources fainter and more distant than have previously been seen because of Arecibo's unrivaled sensitivity. In this paper we detail a precursor survey of this region with PALFA, which observed a subset of the full region (slightly more restrictive in â„“ and |b| ≲ 1°) and detected 45 pulsars. Detections included …

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The Ninja-2 Project: Detecting And Characterizing Gravitational Waveforms Modelled Using Numerical Binary Black Hole Simulations, J. Aasi, B. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia, Mario C. Diaz, Malik Rakhmanov, Joseph D. Romano, Soma Mukherjee, Volker Quetschke, Teviet Creighton, Robert Stone Jun 2014

The Ninja-2 Project: Detecting And Characterizing Gravitational Waveforms Modelled Using Numerical Binary Black Hole Simulations, J. Aasi, B. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia, Mario C. Diaz, Malik Rakhmanov, Joseph D. Romano, Soma Mukherjee, Volker Quetschke, Teviet Creighton, Robert Stone

Physics and Astronomy Faculty Publications and Presentations

The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave (GW) astrophysics communities. The purpose of NINJA is to study the ability to detect GWs emitted from merging binary black holes (BBH) and recover their parameters with next-generation GW observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete BBH hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a ‘blind injection challenge’ similar to that conducted in recent Laser …

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Solution Of Fractional Harmonic Oscillator In A Fractional B-Poly Basis, Muhammad I. Bhatti Jun 2014

Solution Of Fractional Harmonic Oscillator In A Fractional B-Poly Basis, Muhammad I. Bhatti

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

An algorithm for approximating solutions to fractional-order differential equations in fractional polynomial basis is presented. A finite generalized fractional-order basis set is obtained from the modified Bernstein Polynomials, where α is the fractional-order of the modified Bernstein type polynomials (B-polys). The algorithm determines the desired solution in terms of continuous finite number of generalized fractional polynomials in a closed interval and makes use of Galerkin method to calculate the unknown expansion coefficients for constructing the approximate solution to the fractional differential equations. The Caputo’s definition for a fractional derivative is used to evaluate derivatives of the polynomials. Each term in …

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What We Can And Cannot (Yet) Do With Functional Near Infrared Spectroscopy, Megan K. Strait, Matthias Scheutz May 2014

What We Can And Cannot (Yet) Do With Functional Near Infrared Spectroscopy, Megan K. Strait, Matthias Scheutz

Computer Science Faculty Publications and Presentations

Functional near infrared spectroscopy (NIRS) is a relatively new technique complimentary to EEG for the development of brain-computer interfaces (BCIs). NIRS-based systems for detecting various cognitive and affective states such as mental and emotional stress have already been demonstrated in a range of adaptive human–computer interaction (HCI) applications. However, before NIRS-BCIs can be used reliably in realistic HCI settings, substantial challenges oncerning signal processing and modeling must be addressed. Although many of those challenges have been identified previously, the solutions to overcome them remain scant. In this paper, we first review what can be currently done with NIRS, specifically, NIRS-based …

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Cloning And Characterization Of Ef-Tu And Ef-Ts From Streptococcus Pneumoniae, Carlos Eduardo Rivera May 2014

Cloning And Characterization Of Ef-Tu And Ef-Ts From Streptococcus Pneumoniae, Carlos Eduardo Rivera

Theses and Dissertations - UTB/UTPA

Antibiotic resistance is a prevalent threat to public health around the world, and resistance among strains of Streptococcus pneumoniae is growing rapidly. This increasing resistance elevates the demand for new drug discoveries. This research attempts to develop a means to combat S. pneumoniae by targeting protein synthesis for the discovery of new antibacterial agents. Protein synthesis components, elongation factor Tu (EF-Tu) and elongation factor Ts (EF-Ts) facilitate many steps in the biosynthesis of proteins and are therefore essential proteins involved in protein synthesis. EF-Tu and EF-Ts were cloned, expressed, purified, and enzymatically characterized to help develop a screening system that …

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Mri Characterization Of Cobalt Dichloride-N-Acetyl Cysteine (C4) Contrast Agent Marker For Prostate Brachytherapy, Tze Yee Lim, R. Jason Stafford, Rajat J. Kudchadker, Madhuri Sankaranarayanapillai, Geoffrey Ibbott, Arvind Rao, Karen S. Martirosyan, Steven J. Frank May 2014

Mri Characterization Of Cobalt Dichloride-N-Acetyl Cysteine (C4) Contrast Agent Marker For Prostate Brachytherapy, Tze Yee Lim, R. Jason Stafford, Rajat J. Kudchadker, Madhuri Sankaranarayanapillai, Geoffrey Ibbott, Arvind Rao, Karen S. Martirosyan, Steven J. Frank

Physics and Astronomy Faculty Publications and Presentations

Brachytherapy, a radiotherapy technique for treating prostate cancer, involves the implantation of numerous radioactive seeds into the prostate. While the implanted seeds can be easily identified on a CT image, distinguishing the prostate and surrounding soft tissues is not as straightforward. Magnetic Resonance Imaging (MRI) offers superior anatomical delineation, but the seeds appear as dark voids and are difficult to identify, thus creating a conundrum. Cobalt dichloride-N-acetylcysteine (C4) has previously been shown to be promising as an encapsulated contrast agent marker. We performed spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) measurements of C4 solutions with varying cobalt dichloride …

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Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas May 2014

Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Antioxidants are prototypical scavengers of oxygen-free radicals and have been shown to prevent neuroendocrine dysfunction in vertebrates during oxidative stress. In the present study, we investigated whether antioxidant treatment can reverse hypoxia-induced down-regulation of hypothalamic tryptophan hydroxylase (TPH) and serotonergic functions in Atlantic croaker. Hypothalamic neuronal contents of TPH-1 and TPH-2 proteins, serotonin (5-hydroxytryptamine, 5-HT) and its precursor, 5-hydroxytryptophan (5-HTP) as well as hypothalamic TPH-1 and TPH-2 mRNA expression and TPH activity were measured in croaker after exposure to hypoxia and treatment with pharmacological agents. Multiple injections of N-ethylmaleimide, a sulfhydryl alkylating agent, caused comparable decreases in hypothalamic TPHs functions …

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Gauging Wetland Restoration Status Using Benthic-Based Structural And Functional Metrics, Claudia Alejandra Tamez May 2014

Gauging Wetland Restoration Status Using Benthic-Based Structural And Functional Metrics, Claudia Alejandra Tamez

Theses and Dissertations - UTB/UTPA

Efforts to restore Bahia Grande, a 2630 hectare, historically sea grass dominated playa lake, are currently underway and describing its current ecological status is critical to recommending any future physical manipulations to the immense basin. A benthic community based study was conducted on three estuaries in Cameron County, Texas (2012 to 2013) in order to compare the polychaete community dynamics and ecosystem productivity rates of the restored basin to that of two older adjacent reference sites (i.e. South Bay and San Martin Lake) in an effort to gauge system status. All three sites were once contiguous with the Lower Laguna …

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Probabilistic Shortest Time Queries Over Uncertain Road Networks, Yaqing Chen May 2014

Probabilistic Shortest Time Queries Over Uncertain Road Networks, Yaqing Chen

Theses and Dissertations - UTB/UTPA

In many real applications such as location-based services (LBS), map utilities, trip planning, and transportation systems, it is very useful and important to provide query services over spatial road networks. Nowadays we can easily obtain rich traffic information such as the speeds of vehicles on roads. However, due to the inaccuracy of devices or integration in consistencies, the traffic data (i.e., speeds) are often imprecise and uncertain. In this paper, we model road networks by uncertain graphs, which contain edges that are associated with probabilistic velocities. We formalize the problem of probabilistic shortest time query, and we propose time bound …

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A Screening Platform For Identification Of Compounds That Inhibit Protein Synthesis In Pseudomonas Aeruginosa, Yanmei Hu May 2014

A Screening Platform For Identification Of Compounds That Inhibit Protein Synthesis In Pseudomonas Aeruginosa, Yanmei Hu

Theses and Dissertations - UTB/UTPA

Pseudomonas aeruginosa is a Gram-negative pathogenic bacteria and a common cause of nosocomial infections. This pathogen has recently garnered attention due to its pan-resistance. We have developed a poly(U) mRNA-directed aminoacylation/translation (A/T) protein synthesis system from P. aeruginosa. The concentration of each component of the system has been arrived at through multiple rounds of optimization. Poly-phenylalanine synthesis in the system was monitored using scintillation proximity assays (SPA). This system has been used to screen two natural compound libraries (>1100) and a number of the compounds that inhibit greater than 50% of the activity of the system have been identified. …

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Metal Oxide Nanostructures For Energy Conversion And Storage, Xing Sun May 2014

Metal Oxide Nanostructures For Energy Conversion And Storage, Xing Sun

Theses and Dissertations - UTB/UTPA

With the depletion of non-renewable resources and the related problems such as environmental pollutions and global warming effect, the society urgently needs more efficient and controllable energy conversion and storage systems. Three-dimensional ZnO nanoforests were prepared and morphology-tunable, which benefits both of energy conversion and storage systems. Willow-like ZnO nanoforests led the highest conversion efficiency of photoelectrochemical water splitting in reported pure ZnO nanostructures. Compared with nanowire arrays, ZnO@MnO2 nanoforests delivered 5 times higher specific capacitances within the same footprint area. V2O5@PPy exhibited higher specific capacitance and better rate stability than pure V2O5 nanofibers. This work lays the foundation for …

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Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez May 2014

Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez

Theses and Dissertations - UTB/UTPA

Soil fertility and plant nutrition is crucial for a better yield and consistent harvest in the Rio Grande Valley for local farmers growing citrus trees. A field of oranges and a field of grapefruits were monitored and nutrition deficiencies were noticed that played an important role during fruit set. Soil samples that were taken throughout the year were analyzed via a carbon dioxide extraction method that mimics the way plants naturally take up nutrients or extract nutrients from every soil type. Macronutrients such as the N, P, K, Na, Ca, Mg and some of the micronutrients (Zn, Fe, Mn, and …

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Creating An Information Systems Security Culture Through An Integrated Model Of Employees Compliance, Mohammad I. Merhi May 2014

Creating An Information Systems Security Culture Through An Integrated Model Of Employees Compliance, Mohammad I. Merhi

Theses and Dissertations - UTB/UTPA

Employees’ non-compliance with information systems security policies has been identified as a major threat to organizational data and information systems. This dissertation investigates the process underlying information systems security compliance in organizations with the focus on employees. The process model is complex, comprising many normative, attitudinal, psychological, environmental, and organizational factors. Therefore, the study of information security compliance requires a holistic assessment of all these factors. This dissertation seeks to achieve this objective by offering a comprehensive and integrated model of employee behavior especially focused towards information security compliance. The research framework is influenced by the Reciprocal Determinism Theory which …

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Cubic B-Spline: Derivation With Two Applications, Maria Mungia May 2014

Cubic B-Spline: Derivation With Two Applications, Maria Mungia

Theses and Dissertations - UTB/UTPA

We investigate the application of cubic B-spline functions in this work. First, we derive the cubic B-spline functions. Then we use these functions for two applications: one for interpolation and the other for solving boundary value problems. For interpolation, we consider two types of boundary conditions, namely natural and clamped. For boundary value problems, we consider constant coefficient and variable coefficient cases. Examples with numerical results are presented for both applications. Also we compare the results obtained using cubic B-spline functions with the results obtained by other methods. For this investigation, it is observed that cubic B-spline gives better results.

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Topological Pressure And Fractal Dimensions For Bi-Lipschitz Mappings, Hugo E. Olvera May 2014

Topological Pressure And Fractal Dimensions For Bi-Lipschitz Mappings, Hugo E. Olvera

Theses and Dissertations - UTB/UTPA

In this thesis, first we have defined the topological pressure P(t) and then using Banach limit we have determined a unique Borel probability measure µh supported by the invariant set E of a system of bi-Lipschitz mappings where h is the unique zero of the pressure function. Using the topological pressure and the measure µh, under certain condition on bi-Lipschitz constants, we have shown that the fractal dimensions such as the Hausdorff dimension, the packing dimension and the box-counting dimension of the set E are all equal to h. Moreover, it is shown that the h-dimensional Hausdorff measure and the …

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Exponential Replication Of Patterns In The Signal Tile Assembly Model And Experimental Non-Deterministic Assembly Of Lines In The Probabilistic Tile Assembly Model, Alexandra B. Keenan May 2014

Exponential Replication Of Patterns In The Signal Tile Assembly Model And Experimental Non-Deterministic Assembly Of Lines In The Probabilistic Tile Assembly Model, Alexandra B. Keenan

Theses and Dissertations - UTB/UTPA

We introduce the problem of self-replication of rectangular two-dimensional patterns in the practically motivated Signal Tile Assembly Model (STAM), which is an extension of the aTAM. In the first part of this thesis, we construct an exponential pattern replicator that replicates a two-dimensional input pattern over some fixed alphabet of size ϕ with O(ϕ) tile types, O(ϕ) unique glues, and a signal complexity of O(1). In the second part of this thesis, we use a non-deterministic model of tile assembly to significantly reduce the tile complexity of specified-length linear assemblies, which are a particularly important substructure for building more complicated …

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Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani, F. M. Ellis, T. Kottos Apr 2014

Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani, F. M. Ellis, T. Kottos

Physics and Astronomy Faculty Publications and Presentations

Using a pair of coupled RLC cavities we experimentally demonstrate that amplification action can be tamed by a spatially inhomogeneous gain. Under specific conditions we observe the counterintuitive phenomenon of stabilization of the system even when the overall gain provided is increased. This behavior is directly related to lasing shutdown via asymmetric pumping, recently proposed in M. Liertzer et al. [Phys. Rev. Lett. 108, 173901 (2012)]. The analysis of other simple systems reveals the universal nature of the lasing shutdown phenomenon as having its roots in managing impedance matching.

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Communication: Conical Intersections Between Vibrationally Adiabatic Surfaces In Methanol, Mahesh B. Dawadi, David S. Perry Apr 2014

Communication: Conical Intersections Between Vibrationally Adiabatic Surfaces In Methanol, Mahesh B. Dawadi, David S. Perry

Chemistry Faculty Publications and Presentations

A set of seven conical intersections (CI’s) in methanol between vibrationally adiabatic surfaces is reported. The intersecting surfaces represent the energies of the two asymmetric CH stretch vibrations regarded as adiabatic functions of the torsion and COH bend angles. The ab initio data are well described by an extended Zwanziger and Grant (E ⊗ e) model [J. W. Zwanziger and E. R. Grant, J. Chem. Phys. 87, 2954 (1987)] that might also be regarded as an extension of the XHL model [L.-H. Xu, J. T. Hougen, and R. M. Lees, J. Mol. Spectrosc. 293–294, 38 (2013)]. …

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Optical Isolation Via Pt-Symmetric Nonlinear Fano Resonances, F. Nazari, N. Bender, Hamidreza Ramezani, M. K. Moravvej-Farshi, D. N. Christodoulides, T. Kottos Apr 2014

Optical Isolation Via Pt-Symmetric Nonlinear Fano Resonances, F. Nazari, N. Bender, Hamidreza Ramezani, M. K. Moravvej-Farshi, D. N. Christodoulides, T. Kottos

Physics and Astronomy Faculty Publications and Presentations

We show that Fano resonances created by twoPT -symmetric nonlinear micro-resonators coupled to a waveguide, have line-shape and resonance position that depends on the direction of the incident light. We utilize these features in order to induce asymmetric transport, up to 47 dBs, in the optical C-window. Our theoretical proposal requires low input power and does not compromise the power or frequency characteristics of the output signal.

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Gravitational Waves From Known Pulsars: Results From The Initial Detector Era, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, R. X. Adhikari, C. Affeldt, M. Agathos, N. Aggarwal, O. D. Aguiar, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, D. Amariutei, R. A. Anderson, S. B. Anderson, W. G. Anderson, K. Arai, M. C. Araya, C. Arceneaux, J. Areeda, S. Ast, S. M. Aston, P. Astone Apr 2014

Gravitational Waves From Known Pulsars: Results From The Initial Detector Era, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, R. X. Adhikari, C. Affeldt, M. Agathos, N. Aggarwal, O. D. Aguiar, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, D. Amariutei, R. A. Anderson, S. B. Anderson, W. G. Anderson, K. Arai, M. C. Araya, C. Arceneaux, J. Areeda, S. Ast, S. M. Aston, P. Astone

Physics and Astronomy Faculty Publications and Presentations

We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and …

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Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani Apr 2014

Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

Using a pair of coupled RLC cavities we experimentally demonstrate that amplification action can be tamed by a spatially inhomogeneous gain. Under specific conditions we observe the counterintuitive phenomenon of stabilization of the system even when the overall gain provided is increased. This behavior is directly related to lasing shutdown via asymmetric pumping, recently proposed in M. Liertzer et al. [Phys. Rev. Lett. 108, 173901 (2012)]. The analysis of other simple systems reveals the universal nature of the lasing shutdown phenomenon as having its roots in managing impedance matching.

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Fermi-Normal, Optical, And Wave-Synchronous Coordinates For Spacetime With A Plane Gravitational Wave, Malik Rakhmanov Apr 2014

Fermi-Normal, Optical, And Wave-Synchronous Coordinates For Spacetime With A Plane Gravitational Wave, Malik Rakhmanov

Physics and Astronomy Faculty Publications and Presentations

Fermi-normal (FN) coordinates provide a standardized way to describe the effects of gravitation from the point of view of an inertial observer. These coordinates have always been introduced via perturbation expansions and were usually limited to distances much less than the characteristic length scale set by the curvature of spacetime. For a plane gravitational wave this scale is given by its wavelength which defines the domain of validity for these coordinates known as the long-wavelength regime. The symmetry of this spacetime, however, allows us to extend FN coordinates far beyond the long-wavelength regime. Here we present an explicit construction for …

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On Toroidal Knots, Chirality, And Molecules, Ramiro Garza Apr 2014

On Toroidal Knots, Chirality, And Molecules, Ramiro Garza

Theses and Dissertations - UTB/UTPA

The inspiration for this thesis came from two sources: the book When topology meets chemistry: a topological look at molecular chirality, by Erica Flapan [7], which discusses topologically interesting molecules; and the paper All toroidal embeddings of polyhedral graphs in 3-space are chiral, by T. Castle et al., which proves that toroidal embeddings of polyhedra are chiral. Their proof is examined in detail. A possible application of this work, as discussed by the team, would be in molecules which have the structure of a toroidal polyhedral embedding. Various methods of seeking such an example are attempted and discussed.

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The Role Of App Development And Mobile Computing In Motivating The Secondary Mathematics Classroom, Jennifer Lee Marquez Apr 2014

The Role Of App Development And Mobile Computing In Motivating The Secondary Mathematics Classroom, Jennifer Lee Marquez

Theses and Dissertations - UTB/UTPA

An increasing amount of high school students are interested in developing their own mobile application. Incorporating mobile development into the classroom can increase student engagement in the fields of science, technology, engineering, and mathematics. In this paper I present a study done with a group of sophomore level students who created their own mathematics apps with no programming experience. The aim of this study is to assess the knowledge gained and motivational appeal of secondary mathematics students taught basic state of Texas exam concepts with the use of the proposed mobile development labs. Students in this study used algebraic and …

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A Digital Backend For The Low Frequency All Sky Monitor, Louis Percy Dartez Apr 2014

A Digital Backend For The Low Frequency All Sky Monitor, Louis Percy Dartez

Theses and Dissertations - UTB/UTPA

The Low Frequency All Sky Monitor (LoFASM) is a distributed array of dipole antennas that are sensitive to radio frequencies from 10 to 88 MHz. The primary science goals of LoFASM are the detection and study of low-frequency radio transients, a high priority science goal as deemed by the National Research Council's decadal survey. LoFASM consists of antennas and front-end electronics that were originally developed for the Long Wavelength Array (LWA) by the U.S. Naval Research Lab, the University of New Mexico, Virginia Tech, and the Jet Propulsion Laboratory. LoFASM, funded by the U.S. Department of Defense, will initially consist …

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Temperature And Relative Humidity Effects On Water Loss And Hemolymph Osmolality Of Littoraria Angulifera (Lamarck, 1822), Phillip J. Rose Apr 2014

Temperature And Relative Humidity Effects On Water Loss And Hemolymph Osmolality Of Littoraria Angulifera (Lamarck, 1822), Phillip J. Rose

Theses and Dissertations - UTB/UTPA

Desiccation stress is considered to be one of the more significant determining factors that influence how organisms are distributed in the marine littoral. Gastropods living above the high tide mark, referred to as eulittoral fringe gastropods are not wetted as regularly and face unpredictable and prolonged periods of emersion. Consequently, adaptations displayed by eulittoral fringe gastropods are aimed at minimizing water loss and surviving prolonged periods of desiccation stress. Littoraria angulifera, is a tropically distributed marine eulittoral fringe gastropod. Because L. angulifera spends a majority of its time emersed there was interest in studying how the weight loss and hemolymph …

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Prepubertal Exposure To Arsenic(Iii) Suppresses Circulating Insulin-Like Growth Factor-1 (Igf-1) Delaying Sexual Maturation In Female Rats, Michael P. Reilly, James C. Saca, Alina Hamilton, Rene F. Solano, Jesse R. Rivera, Wendy Innis-Whitehouse, Jason Parsons, Robert K. Dearth Apr 2014

Prepubertal Exposure To Arsenic(Iii) Suppresses Circulating Insulin-Like Growth Factor-1 (Igf-1) Delaying Sexual Maturation In Female Rats, Michael P. Reilly, James C. Saca, Alina Hamilton, Rene F. Solano, Jesse R. Rivera, Wendy Innis-Whitehouse, Jason Parsons, Robert K. Dearth

Biology Faculty Publications and Presentations

Arsenic (As) is a prevalent environmental toxin readily accessible for human consumption and has been identified as an endocrine disruptor. However, it is not known what impact As has on female sexual maturation. Therefore, in the present study, we investigated the effects of prepubertal exposure on mammary gland development and pubertal onset in female rats. Results showed that prepubertal exposure to 10 mg/kg of arsenite (As(III)) delayed vaginal opening (VO) and prepubertal mammary gland maturation. We determined that As accumulates in the liver, disrupts hepatocyte function and suppresses serum levels of the puberty related hormone insulin-like growth factor 1 (IGF-1) …

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Gravitational Wave Hotspots: Ranking Potential Locations Of Single-Source Gravitational Wave Emission, Joseph Simon, Abigail Polin, Andrea Lommen, Ben Stappers, Lee Samuel Finn, F. A. Jenet, B. Christy Mar 2014

Gravitational Wave Hotspots: Ranking Potential Locations Of Single-Source Gravitational Wave Emission, Joseph Simon, Abigail Polin, Andrea Lommen, Ben Stappers, Lee Samuel Finn, F. A. Jenet, B. Christy

Physics and Astronomy Faculty Publications and Presentations

The steadily improving sensitivity of pulsar timing arrays (PTAs) suggests that gravitational waves (GWs) from supermassive black hole binary (SMBHB) systems in the nearby universe will be detectable sometime during the next decade. Currently, PTAs assume an equal probability of detection from every sky position, but as evidence grows for a non-isotropic distribution of sources, is there a most likely sky position for a detectable single source of GWs? In this paper, a collection of Galactic catalogs is used to calculate various metrics related to the detectability of a single GW source resolvable above a GW background, assuming that every …

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Concept Of A Reflective Power Limiter Based On Nonlinear Localized Modes, Elena Makri, Hamidreza Ramezani, Tsampikos Kottos, Ilya Vitebsky Mar 2014

Concept Of A Reflective Power Limiter Based On Nonlinear Localized Modes, Elena Makri, Hamidreza Ramezani, Tsampikos Kottos, Ilya Vitebsky

Physics and Astronomy Faculty Publications and Presentations

Optical limiters are designed to transmit low-intensity light, while blocking the light with excessively high intensity. A typical passive limiter absorbs excessive electromagnetic energy, which can cause its overheating and destruction. We propose the concept of a photonic reflective limiter based on resonance transmission via a localized mode. Such a limiter does not absorb the high-level radiation, but rather reflects it back to space. Importantly, the nearly total reflection occurs within a broad frequency range and direction of incidence. The same concept can be applied to infrared and microwave frequencies.

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