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Disorder Driven Asymmetry And Singular Red Emission In Doped Lu2hf2o7 Nanocrystals With No Charge Compensating Defects, Santosh K. Gupta, Mitzy A. Penilla Garcia, Jose P. Zuniga, Bhupendra B. Srivastava, Yuanbing Mao Jul 2021

Disorder Driven Asymmetry And Singular Red Emission In Doped Lu2hf2o7 Nanocrystals With No Charge Compensating Defects, Santosh K. Gupta, Mitzy A. Penilla Garcia, Jose P. Zuniga, Bhupendra B. Srivastava, Yuanbing Mao

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

High performance luminescent materials possess low symmetry, high color purity, no charge compensating defects, and high quantum yield. In this work, we have synthesized Lu2Hf2O7 (LuHO) and Lu2Hf2O7:Eu3+ (LuHOE) nanocrystals (NCs) using a molten salt synthesis and confirmed that both are stabilized in defect fluorite structure with a high degree of structural disordering. The LuHO NCs depicted green emission under ultraviolet irradiation, which decreases and increases after being treated in oxidizing and reducing environments, respectively, confirming the role of oxygen vacancies in the emission process. The LuHOE NCs (i) show excitation wavelength-dependent host to dopant energy transfer efficiency, …

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Deep-Sea Biodiversity At The Extremes Of The Salas Y Gómez And Nazca Ridges With Implications For Conservation, Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton, Daniel Wagner Jun 2021

Deep-Sea Biodiversity At The Extremes Of The Salas Y Gómez And Nazca Ridges With Implications For Conservation, Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton, Daniel Wagner

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Salas y Gómez and Nazca ridges are underwater mountain chains that stretch across 2,900 km in the southeastern Pacific and are recognized for their high biodiversity value and unique ecological characteristics. Explorations of deep-water ecosystems have been limited in this region, and elsewhere globally. To characterize community composition of mesophotic and deep-sea demersal fauna at seamounts in the region, we conducted expeditions to Rapa Nui (RN) and Salas y Gómez (SyG) islands in 2011 and Desventuradas Islands in 2013. Remote autonomous baited-cameras were used to conduct stationary video surveys between 150–1,850 m at RN/SyG (N = 20) and 75–2,363 …

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Constraints On Cosmic Strings Using Data From The Third Advanced Ligo–Virgo Observing Run, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Karla E. Ramirez, W. H. Wang Jun 2021

Constraints On Cosmic Strings Using Data From The Third Advanced Ligo–Virgo Observing Run, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Karla E. Ramirez, W. H. Wang

Physics & Astronomy Faculty Publications

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop …

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Tests Of General Relativity With Binary Black Holes From The Second Ligo-Virgo Gravitational-Wave Transient Catalog, R. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, Wenhui Wang Jun 2021

Tests Of General Relativity With Binary Black Holes From The Second Ligo-Virgo Gravitational-Wave Transient Catalog, R. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, Wenhui Wang

Physics & Astronomy Faculty Publications

Gravitational waves enable tests of general relativity in the highly dynamical and strong-field regime. Using events detected by LIGO-Virgo up to 1 October 2019, we evaluate the consistency of the data with predictions from the theory. We first establish that residuals from the best-fit waveform are consistent with detector noise, and that the low- and high-frequency parts of the signals are in agreement. We then consider parametrized modifications to the waveform by varying post-Newtonian and phenomenological coefficients, improving past constraints by factors of ∼2; we also find consistency with Kerr black holes when we specifically target signatures of the spin-induced …

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Miscanthus Biomass For Alternative Energy Production, Jikai Zhao, Donghai Wang, Valentina Pidlisnyuk, Larry E. Erickson Jun 2021

Miscanthus Biomass For Alternative Energy Production, Jikai Zhao, Donghai Wang, Valentina Pidlisnyuk, Larry E. Erickson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Biomass such as Miscanthus that is produced using phytoremediation can be used as a biofuel. In some locations it is used for heating homes that are located close to where it is produced. This chapter considers alternative energy technologies for Miscanthus and other plants, including liquid fuels such as ethanol, methane from anaerobic digestion, and pyrolysis (thermal Processing). Pretreatment alternatives to convert cellulose to glucose are reviewed because the economics of ethanol production from Miscanthus are impacted by the efficiency of cellulose hydrolysis to glucose. Size reduc tion of Miscanthus is often the first step in the process because enzymes …

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Miscanthus As Raw Materials For Bio-Based Products, Valentina Pidlisnyuk, Larry E. Erickson, Donghai Wang, Jikai Zhao, Tatyana Stefanovska, John R. Schlup Jun 2021

Miscanthus As Raw Materials For Bio-Based Products, Valentina Pidlisnyuk, Larry E. Erickson, Donghai Wang, Jikai Zhao, Tatyana Stefanovska, John R. Schlup

School of Earth, Environmental, & Marine Sciences Faculty Publications

There is great interest in products from Miscanthus because large quantities of biomass can be produced annually. There are simple uses such as bedding for animals, mulch for horticulture applications, and insulation to improve energy conservation. Miscanthus has excellent natural absorbent qualities which makes it very attractive for spill management and as a bedding material. Compostable foodservice ware has been produced from Miscanthus to replace products from plastic that do not biodegrade. Building applications include fiber board, particleboard, and composites. Miscanthus has high-quality cel lulose for material applications and is an excellent source of cellulose where high quality is important. …

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Quark Matter Contribution To The Heat Capacity Of Magnetized Neutron Stars, Efrain J. Ferrer, Vivian De La Incera, P. Sanson Jun 2021

Quark Matter Contribution To The Heat Capacity Of Magnetized Neutron Stars, Efrain J. Ferrer, Vivian De La Incera, P. Sanson

Physics & Astronomy Faculty Publications

In this paper, we find the heat capacity of the magnetic dual chiral density wave (MDCDW) phase of dense quark matter and use it to explore the feasibility of this phase for a neutron star interior. MDCDW is a spatially inhomogeneous phase of quark matter known to be favored at intermediate densities over the chirally symmetric phase and the color-flavor-locked superconducting phase. By comparing our result to the lower limit of the core heat capacity established from observations of transiently accreting neutron stars, we show that the heat capacity of MDCDW quark matter is well above that lower limit and …

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Gwtc-2: Compact Binary Coalescences Observed By Ligo And Virgo During The First Half Of The Third Observing Run, R. Abbott, T. D. Abbott, S. Abraham, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, W. H. Wang Jun 2021

Gwtc-2: Compact Binary Coalescences Observed By Ligo And Virgo During The First Half Of The Third Observing Run, R. Abbott, T. D. Abbott, S. Abraham, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, W. H. Wang

Physics & Astronomy Faculty Publications

We report on gravitational-wave discoveries from compact binary coalescences detected by Advanced LIGO and Advanced Virgo in the first half of the third observing run (O3a) between 1 April 2019 15∶00 UTC and 1 October 2019 15∶00 UTC. By imposing a false-alarm-rate threshold of two per year in each of the four search pipelines that constitute our search, we present 39 candidate gravitational-wave events. At this threshold, we expect a contamination fraction of less than 10%. Of these, 26 candidate events were reported previously in near-real time through gamma-ray coordinates network notices and circulars; 13 are reported here for the …

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Dna-Topology Simplification By Topoisomerases, Andreas Hanke, Riccardo Ziraldo, Stephen D. Levene Jun 2021

Dna-Topology Simplification By Topoisomerases, Andreas Hanke, Riccardo Ziraldo, Stephen D. Levene

Physics & Astronomy Faculty Publications

The topological properties of DNA molecules, supercoiling, knotting, and catenation, are intimately connected with essential biological processes, such as gene expression, replication, recombination, and chromosome segregation. Non-trivial DNA topologies present challenges to the molecular machines that process and maintain genomic information, for example, by creating unwanted DNA entanglements. At the same time, topological distortion can facilitate DNA-sequence recognition through localized duplex unwinding and longer-range loop-mediated interactions between the DNA sequences. Topoisomerases are a special class of essential enzymes that homeostatically manage DNA topology through the passage of DNA strands. The activities of these enzymes are generally investigated using circular DNA …

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Domes Over Curves, Alexey Glazyrin, Igor Pak Jun 2021

Domes Over Curves, Alexey Glazyrin, Igor Pak

School of Mathematical & Statistical Sciences Faculty Publications

A closed piecewise linear curve is called integral if it is comprised of unit intervals. Kenyon's problem asks whether for every integral curve γ in ℝ3, there is a dome over γ, i.e. whether γ is a boundary of a polyhedral surface whose faces are equilateral triangles with unit edge lengths. First, we give an algebraic necessary condition when γ is a quadrilateral, thus giving a negative solution to Kenyon's problem in full generality. We then prove that domes exist over a dense set of integral curves. Finally, we give an explicit construction of domes over all regular n-gons.

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Quantization Coefficients For Uniform Distributions On The Boundaries Of Regular Polygons, Joel Hansen, Itzamar Marquez, Mrinal Kanti Roychowdhury, Eduardo Torres Jun 2021

Quantization Coefficients For Uniform Distributions On The Boundaries Of Regular Polygons, Joel Hansen, Itzamar Marquez, Mrinal Kanti Roychowdhury, Eduardo Torres

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, we give a general formula to determine the quantization coefficients for uniform distributions defined on the boundaries of different regular m-sided polygons inscribed in a circle. The result shows that the quantization coefficient for the uniform distribution on the boundary of a regular m-sided polygon inscribed in a circle is an increasing function of m, and approaches to the quantization coefficient for the uniform distribution on the circle as m tends to infinity.

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Diving Below The Spin-Down Limit: Constraints On Gravitational Waves From The Energetic Young Pulsar Psr J0537-6910, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Karla E. Ramirez, W. H. Wang Jun 2021

Diving Below The Spin-Down Limit: Constraints On Gravitational Waves From The Energetic Young Pulsar Psr J0537-6910, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Karla E. Ramirez, W. H. Wang

Physics & Astronomy Faculty Publications

We present a search for quasi-monochromatic gravitational-wave signals from the young, energetic X-ray pulsar PSR J0537-6910 using data from the second and third observing runs of LIGO and Virgo. The search is enabled by a contemporaneous timing ephemeris obtained using Neutron star Interior Composition Explorer (NICER) data. The NICER ephemeris has also been extended through 2020 October and includes three new glitches. PSR J0537-6910 has the largest spin-down luminosity of any pulsar and exhibits fRequent and strong glitches. Analyses of its long-term and interglitch braking indices provide intriguing evidence that its spin-down energy budget may include gravitational-wave emission from a …

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Energy On Spheres And Discreteness Of Minimizing Measures, Dmitriy Bilyk, Alexey Glazyrin, Ryan Matzke, Josiah Park, Oleksandr Vlasiuk Jun 2021

Energy On Spheres And Discreteness Of Minimizing Measures, Dmitriy Bilyk, Alexey Glazyrin, Ryan Matzke, Josiah Park, Oleksandr Vlasiuk

School of Mathematical & Statistical Sciences Faculty Publications

In the present paper we study the minimization of energy integrals on the sphere with a focus on an interesting clustering phenomenon: for certain types of potentials, optimal measures are discrete or are supported on small sets. In particular, we prove that the support of any minimizer of the p-frame energy has empty interior whenever p is not an even integer. A similar effect is also demonstrated for energies with analytic potentials which are not positive definite. In addition, we establish the existence of discrete minimizers for a large class of energies, which includes energies with polynomial potentials.

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A Game-Theoretic Framework To Regulate Freeriding In Inter-Provider Spectrum Sharing, Mostafizur Rahman, Murat Yuksel, Thomas Quint Jun 2021

A Game-Theoretic Framework To Regulate Freeriding In Inter-Provider Spectrum Sharing, Mostafizur Rahman, Murat Yuksel, Thomas Quint

Electrical and Computer Engineering Faculty Publications

Primary-secondary spectrum sharing is limited in terms of design space, and may not be sufficient to meet the ever-increasing demand of connectivity and high signal quality. The next step to increase spectrum sharing efficiency is to design markets where sharing takes place among primary providers rather than leaving it to the limited case where the primary licensee is idle. Attaining contractual spectrum sharing among primary providers, a.k.a. co-primary or inter-provider sharing, involves additional costs for the users, e.g., roaming fee. Co-primary spectrum sharing without additional charge to the users poses two major challenges: a) regulatory approaches must be introduced to …

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Fabrication Of Nd3+ And Yb3+ Doped Nir Emitting Nano Fluorescent Probe: A Candidate For Bioimaging Applications, D. Karthickraja, G. A. Kumar, D. K. Sardar, S. Karthi, Gamage C. Dannangoda, Karen S. Martirosyan, M. Prasath, M. Gowri, E. L. Girija Jun 2021

Fabrication Of Nd3+ And Yb3+ Doped Nir Emitting Nano Fluorescent Probe: A Candidate For Bioimaging Applications, D. Karthickraja, G. A. Kumar, D. K. Sardar, S. Karthi, Gamage C. Dannangoda, Karen S. Martirosyan, M. Prasath, M. Gowri, E. L. Girija

Physics & Astronomy Faculty Publications

The intentional design of rare earth doped luminescent architecture exhibits unique optical properties and it can be considered as a promising and potential probe for optical imaging applications. Calcium fluoride (CaF2) nanoparticles doped with optimum concentration of Nd3+ and Yb3+ as sensitizer and activator, respectively, were synthesized by wet precipitation method and characterized by x-ray diffraction (XRD) and photoluminescence. In spite of the fact that the energy transfer takes place from Nd3+ to Yb3+, the luminescence intensity was found to be weak due to the lattice defects generated from the doping of trivalent cations (Nd3+ and Yb3+) for divalent host …

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Environmental Noise In Advanced Ligo Detectors, P. Nguyen, R. M. S. Schofield, A. Effler, C. Austin, V. B. Adya, M. Ball, S. Banagiri, K. Banowetz, C. Billman, Karla E. Ramirez Jun 2021

Environmental Noise In Advanced Ligo Detectors, P. Nguyen, R. M. S. Schofield, A. Effler, C. Austin, V. B. Adya, M. Ball, S. Banagiri, K. Banowetz, C. Billman, Karla E. Ramirez

Physics & Astronomy Faculty Publications

The sensitivity of the advanced LIGO detectors to gravitational waves can be affected by environmental disturbances external to the detectors themselves. Since the transition from the former initial LIGO phase, many improvements have been made to the equipment and techniques used to investigate these environmental effects. These methods have aided in tracking down and mitigating noise sources throughout the first three observing runs of the advanced detector era, keeping the ambient contribution of environmental noise below the background noise levels of the detectors. In this paper we describe the methods used and how they have led to the mitigation of …

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Approaching The Motional Ground State Of A 10-Kg Object, Chris Whittle, E. D. Hall, S. E. Dwyer, N. Mavalvala, Vivishek Sudhir, R. Abbott, A. Ananyeva, C. Austin, L. Barsotti, Karla E. Ramirez Jun 2021

Approaching The Motional Ground State Of A 10-Kg Object, Chris Whittle, E. D. Hall, S. E. Dwyer, N. Mavalvala, Vivishek Sudhir, R. Abbott, A. Ananyeva, C. Austin, L. Barsotti, Karla E. Ramirez

Physics & Astronomy Faculty Publications

The motion of a mechanical object— even a human-sized object— should be governed by the rules of quantum mechanics. Coaxing them into a quantum state is, however, difficult: the thermal environment effectively masks any quantum signature of the object’s motion. Indeed, it also masks effects of proposed modifications of quantum mechanics at large mass scales. We prepare the center-of-mass motion of a 10 kg mechanical oscillator in a state with an average phonon occupation of 10.8. The reduction in oscillator temperature, from room temperature to 77 nK, represents a 100-fold improvement in the reduction of temperature of a solid-state mechanical …

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Hexagon Tilings Of The Plane That Are Not Edge-To-Edge, Dirk Frettlöh, Alexey Glazyrin, Z. Lángi Jun 2021

Hexagon Tilings Of The Plane That Are Not Edge-To-Edge, Dirk Frettlöh, Alexey Glazyrin, Z. Lángi

School of Mathematical & Statistical Sciences Faculty Publications

An irregular vertex in a tiling by polygons is a vertex of one tile and belongs to the interior of an edge of another tile. In this paper we show that for any integer k≥3, there exists a normal tiling of the Euclidean plane by convex hexagons of unit area with exactly k irregular vertices. Using the same approach we show that there are normal edge-to-edge tilings of the plane by hexagons of unit area and exactly k many n-gons (n>6) of unit area. A result of Akopyan yields an upper bound for k depending on the maximal diameter …

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Local Zeta Functions And Koba–Nielsen String Amplitudes, Miriam Bocardo-Gaspar, Hugo García-Compeán, Edgar Y. López, Wilson A. Zúñiga-Galindo May 2021

Local Zeta Functions And Koba–Nielsen String Amplitudes, Miriam Bocardo-Gaspar, Hugo García-Compeán, Edgar Y. López, Wilson A. Zúñiga-Galindo

School of Mathematical & Statistical Sciences Faculty Publications

This article is a survey of our recent work on the connections between Koba–Nielsen amplitudes and local zeta functions (in the sense of Gel’fand, Weil, Igusa, Sato, Bernstein, Denef, Loeser, etc.). Our research program is motivated by the fact that the p-adic strings seem to be related in some interesting ways with ordinary strings. p-Adic string amplitudes share desired characteristics with their Archimedean counterparts, such as crossing symmetry and invariance under Möbius transformations. A direct connection between p-adic amplitudes and the Archimedean ones is through the limit p→1. Gerasimov and Shatashvili studied the limit p→1 of the p-adic effective action …

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Optimal Partial Boundary Condition For Degenerate Parabolic Equations, Huashui Zhan, Zhaosheng Feng May 2021

Optimal Partial Boundary Condition For Degenerate Parabolic Equations, Huashui Zhan, Zhaosheng Feng

School of Mathematical & Statistical Sciences Faculty Publications

For the stability of the non-Newtonian fluid equation∂u∂t−div(a(x)|∇u|p−2∇u)−N∑i=1bi(x)Diu+c(x,t)u=f(x,t),where a(x)|x∈Ω>0, a(x)|x∈∂Ω=0 and bi(x)∈C1(¯¯¯Ω), we know that the degeneracy of a(x) may make the usual Dirichlet boundary value condition overdetermined and only a partial boundary value condition is expected. How to depict the geometric characteristic of the partial boundary value condition has been a long-time standing open problem. In this study, an optimal partial boundary value condition has been proposed, and the stability of weak solutions based on this partial boundary value condition is established. When the rate of the diffusion coefficient decays to zero, we explore how it affects the …

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In-Depth Analysis Of N2o Fluxes In Tropical Forest Soils Of The Congo Basin Combining Isotope And Functional Gene Analysis, Nora Gallarotti, Matti Barthel, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Marijn Bauters, Simon Baumgartner, Travis W. Drake, Pascal Boeckx, Joachim Mohn, Manon Longepierre May 2021

In-Depth Analysis Of N2o Fluxes In Tropical Forest Soils Of The Congo Basin Combining Isotope And Functional Gene Analysis, Nora Gallarotti, Matti Barthel, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Marijn Bauters, Simon Baumgartner, Travis W. Drake, Pascal Boeckx, Joachim Mohn, Manon Longepierre

School of Earth, Environmental, & Marine Sciences Faculty Publications

Primary tropical forests generally exhibit large gaseous nitrogen (N) losses, occurring as nitric oxide (NO), nitrous oxide (N2O) or elemental nitrogen (N2). The release of N2O is of particular concern due to its high global warming potential and destruction of stratospheric ozone. Tropical forest soils are predicted to be among the largest natural sources of N2O; however, despite being the world’s second-largest rainforest, measurements of gaseous N-losses from forest soils of the Congo Basin are scarce. In addition, long-term studies investigating N2O fluxes from different forest ecosystem types (lowland and montane forests) are scarce. In this study we show that …

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Infectious Disease Transmission By Arline Travel, Daniele Provenzano, Sofy Barocio May 2021

Infectious Disease Transmission By Arline Travel, Daniele Provenzano, Sofy Barocio

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Improvements in aviation technology have led to considerable growth of domestic and international flights worldwide especially during the past four decades. Commercial flights have increased the movement of and have connected people from virtually all corners of the globe since the end of World War II to exceed 3 billion passengers a year since 2013: a sizable proportion of the global human population. Flight times have decreased considerably from the onset of commercial aviation and the range of airliners has extended substantially. A passenger harboring an infectious agent embarking a flight on one continent can be deplaning on another continent …

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Population Properties Of Compact Objects From The Second Ligo–Virgo Gravitational-Wave Transient Catalog, R. Abbott, T. D. Abbott, S. Abraham, Ofek Birnholtz, F. Acernese, Teviet Creighton, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, W. H. Wang May 2021

Population Properties Of Compact Objects From The Second Ligo–Virgo Gravitational-Wave Transient Catalog, R. Abbott, T. D. Abbott, S. Abraham, Ofek Birnholtz, F. Acernese, Teviet Creighton, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, W. H. Wang

Physics & Astronomy Faculty Publications

We report on the population of 47 compact binary mergers detected with a false-alarm rate of < in the second LIGO–Virgo Gravitational-Wave Transient Catalog. We observe several characteristics of the merging binary black hole (BBH) population not discernible until now. First, the primary mass spectrum contains structure beyond a power law with a sharp high-mass cutoff; it is more consistent with a broken power law with a break at or a power law with a Gaussian feature peaking at (90% credible interval). While the primary mass distribution must extend to or beyond, only of systems have primary masses greater than . Second, we find that a fraction of BBH systems have component spins misaligned with the orbital angular momentum, giving rise to precession of the orbital plane. Moreover, %–% of BBH systems have spins tilted by more than 90°, giving rise to a negative effective inspiral spin parameter, . Under the assumption that such systems can only be formed by dynamical interactions, we infer that between 25% and 93% of BBHs with nonvanishing are dynamically assembled. Third, we estimate merger rates, finding for BBHs and for binary neutron stars. We find that the BBH rate likely increases with redshift ( credibility) but not faster than the star formation rate ( credibility). Additionally, we examine recent exceptional events in the context of our population models, finding that the asymmetric masses of GW190412 and the high component masses of GW190521 are consistent with our models, but the low secondary mass of GW190814 makes it an outlier.

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Tidal Deformability Of Strange Stars And The Gw170817 Event, Odilon Lourenço, Cesar H. Lenzi, Mariana Dutra, Efrain J. Ferrer, Vivian De La Incera, Laura Paulucci, J. E. Horvath May 2021

Tidal Deformability Of Strange Stars And The Gw170817 Event, Odilon Lourenço, Cesar H. Lenzi, Mariana Dutra, Efrain J. Ferrer, Vivian De La Incera, Laura Paulucci, J. E. Horvath

Physics & Astronomy Faculty Publications

In this work we consider strange stars formed by quark matter in the color-flavor-locked (CFL) phase of color superconductivity. The CFL phase is described by a Nambu-Jona-Lasinio model with four-fermion vector and diquark interaction channels. The effect of the color superconducting medium on the gluons are incorporated into the model by including the gluon self-energy in the thermodynamic potential. We construct parametrizations of the model by varying the vector coupling GV and comparing the results to the data on tidal deformability from the GW170817 event, the observational data on maximum masses from massive pulsars such as the MSP J0740+6620, and …

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Environmental Education And Awareness: The Present And Future Key To The Sustainable Management Of Ramsar Convention Sites In Kenya, Parita Shah, George Atisa May 2021

Environmental Education And Awareness: The Present And Future Key To The Sustainable Management Of Ramsar Convention Sites In Kenya, Parita Shah, George Atisa

Public Affairs and Security Studies Faculty Publications

The Ramsar wetland sites are important habitats for biodiversity and provide ecological services to communities that otherwise have no access to water resources. In Kenya, some wetlands are more prominent and are recognized worldwide as tourist hot spots, biodiversity-rich zones and wildlife habitats. However, these wetlands face overexploitation and degradation from surrounding communities. The efforts to halt underlying threats and the projected declines in the size and quality of inland wetlands at local levels are not sufficient. The question guiding this study is as follows: to what extent do a Ramsar designation and formal and informal education support communities and …

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Study Of Efficient Methods Of Detection And Reconstruction Of Gravitational Waves From Nonrotating 3d General Relativistic Core Collapse Supernovae Explosion Using Multilayer Signal Estimation Method, Soma Mukherjee, Gaukhar Nurbek, Oscar Valdez May 2021

Study Of Efficient Methods Of Detection And Reconstruction Of Gravitational Waves From Nonrotating 3d General Relativistic Core Collapse Supernovae Explosion Using Multilayer Signal Estimation Method, Soma Mukherjee, Gaukhar Nurbek, Oscar Valdez

Physics & Astronomy Faculty Publications

In the post-detection era of gravitational wave (GW) astronomy, core collapse supernovae (CCSN) are one of the most interesting potential sources of signals arriving at the Advanced LIGO detectors. Mukherjee et al. have developed and implemented a new method to search for GW signals from the CCSN search based on a multistage, high accuracy spectral estimation to effectively achieve higher detection signal to noise ratio (SNR). The study has been further enhanced by incorporation of a convolutional neural network (CNN) to significantly reduce false alarm rates (FAR). The combined pipeline is termed multilayer signal estimation (MuLaSE) that works in an …

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Disentangling The Effects Of Vapor Pressure Deficit And Soil Water Availability On Canopy Conductance In A Seasonal Tropical Forest During The 2015 El Niño Drought, Yilin Fang, L. Ruby Leung, Brett T. Wolfe, Matteo Detto, Ryan G. Knox, Bryan Powell, Charlotte Grossiord, Chonggang Xu, Bradley O. Christoffersen, Pierre Gentine May 2021

Disentangling The Effects Of Vapor Pressure Deficit And Soil Water Availability On Canopy Conductance In A Seasonal Tropical Forest During The 2015 El Niño Drought, Yilin Fang, L. Ruby Leung, Brett T. Wolfe, Matteo Detto, Ryan G. Knox, Bryan Powell, Charlotte Grossiord, Chonggang Xu, Bradley O. Christoffersen, Pierre Gentine

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Water deficit in the atmosphere and soil are two key interactive factors that constrain transpiration and vegetation productivity. It is not clear which of these two factors is more important for the water and carbon flux response to drought stress in ecosystems. In this study, field data and numerical modeling were used to isolate their impact on evapotranspiration (ET) and gross primary productivity (GPP) at a tropical forest site in Barro Colorado Island (BCI), Panama, focusing on their response to the drought induced by the El Niño event of 2015–2016. Numerical simulations were performed using a plant hydrodynamic scheme (HYDRO) …

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Development Of A Wearable Finger Exoskeleton For Rehabilitation, Carlos Hernandez-Santos, Yasser A. Davizón, Alejandro Said, Rogelio Soto, L. C. Felix-Harran, Adriana Vargas-Martinez May 2021

Development Of A Wearable Finger Exoskeleton For Rehabilitation, Carlos Hernandez-Santos, Yasser A. Davizón, Alejandro Said, Rogelio Soto, L. C. Felix-Harran, Adriana Vargas-Martinez

Electrical and Computer Engineering Faculty Publications

This research work shows a new architecture of a novel wearable finger exoskeleton for rehabilitation; the proposed design consists of a one degree of freedom mechanism that generates the flexion and extension movement for the proximal, medial and distal phalange of the fingers to assist patients during the rehabilitation process, after neurological trauma, such as a stroke. The anatomy and anthropometric measures for the hand were used to define the design of the mechanism. In the analytic part, the representative equations for the forward and inverse kinematic analysis of the fingers are obtained, also a dynamic analysis is presented. The …

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Characterization Of The Rf Magnetron Sputtered P-Si & N-Si On Si Substrate And Effect Of Process Parameters On Their Structural & Electrical Properties, Prosanto Biswas May 2021

Characterization Of The Rf Magnetron Sputtered P-Si & N-Si On Si Substrate And Effect Of Process Parameters On Their Structural & Electrical Properties, Prosanto Biswas

Theses and Dissertations

In our work, we applied Taguchi Signal-to-noise (SNR) analysis to investigate the effect of varying three process parameters, namely- sputtering power, working pressure, and Ar gas flow rate on the surface and morphological properties of the RF sputtered p-Si and n-Si on Si substrate. We also inspected the contribution of process parameters on those properties by applying Analysis of Variance (ANOVA). Characteristics of thin films fabricated by RF magnetron sputtering vary with the recipes. Process parameters such as power, pressure, process gas flow rate, substrate temperature, and target to substrate distance determine the quality of the thin films. Some of …

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Removal Of Arsenic (Iii) And Arsenic (V) From Aqueous Solution Via Solanum Lycopersicum Phytoremediation And Essential Nutrient Analysis, Grecia W. Garcia Salazar May 2021

Removal Of Arsenic (Iii) And Arsenic (V) From Aqueous Solution Via Solanum Lycopersicum Phytoremediation And Essential Nutrient Analysis, Grecia W. Garcia Salazar

Theses and Dissertations

ICP-OES was used to investigate the uptake of arsenic (V) and arsenic (III) from aqueous solution using tomato seedlings. The effect of arsenic on essential nutrient uptake by tomato was analyzed. The experiment was performed at three levels of arsenic: 1ppm, 2 ppm and 5 ppm [added as sodium arsenate (Na3AsO4) and arsenic trioxide (As2O3)], in nutrient solution. Plants remained in solution for two weeks. Arsenic accumulation depended on arsenic concentration in solution, when exposed to higher arsenic concentrations the plant uptake increased. The highest arsenic accumulation was found in roots, followed by stems and leaves in that order. Essential …

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