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Critical Mathematics Teacher Noticing: Using Online Technology To Explore How Pre-Service Teachers Of Color Confront Their Peers’ Racial Positionings Of Children, Theodore Chao, Melissa Adams Corral Jan 2018

Critical Mathematics Teacher Noticing: Using Online Technology To Explore How Pre-Service Teachers Of Color Confront Their Peers’ Racial Positionings Of Children, Theodore Chao, Melissa Adams Corral

Teaching and Learning Faculty Publications

Mathematics teacher noticing is a construct used heavily in research around mathematics teaching and mathematics teacher education. However, just as a focus on noticing draws attention to what a teacher “sees”, a focus on what a teacher does NOT “see” is equally important. In this study, we utilize an online video commenting tool to analyze what elementary pre-service teachers of color notice about the language and positioning of case study students through four-weeks of problem solving interviews. This tool served as a space for teachers of color to confront the racist ideologies present in how their peers positioned students.


Molecular Modulation Of Osteoblasts And Osteoclasts In Type 2 Diabetes, Selvalakshmi Rathinavelu, Crissy Guidry-Elizondo, Jameela Banu Jan 2018

Molecular Modulation Of Osteoblasts And Osteoclasts In Type 2 Diabetes, Selvalakshmi Rathinavelu, Crissy Guidry-Elizondo, Jameela Banu

Health & Biomedical Sciences Faculty Publications

Diabetes is a common disease affecting majority of populations worldwide. Since 1980, there has been an increase in the number of people diagnosed as prediabetic and diabetic. Diabetes is characterized by high levels of circulating glucose and leads to most microvascular and macrovascular complications such as retinopathy, nephropathy, neuropathy, stroke, and myocardial infarction. Bone marrow vascular disruption and increased adiposity are also linked to various complications in type II diabetes mellitus. In addition to these complications, type 2 diabetic patients also have fragile bones caused by faulty mineralization mainly due to increased adiposity among diabetic patients that affects both osteoblast …


Ecological Resilience Indicators For Salt Marsh Ecosystems, Scott T. Allen, Camille L. Stagg, Jorge Brenner, Kathleen L. Goodin, Don Faber-Langendoen, Christopher A. Gabler, Katherine Wirt Ames Jan 2018

Ecological Resilience Indicators For Salt Marsh Ecosystems, Scott T. Allen, Camille L. Stagg, Jorge Brenner, Kathleen L. Goodin, Don Faber-Langendoen, Christopher A. Gabler, Katherine Wirt Ames

School of Earth, Environmental, & Marine Sciences Faculty Publications

Salt marshes are coastal ecosystems within the intertidal zone, characterized by hypoxic, saline, soil conditions and low biodiversity. Low diversity arises from frequent disturbance and stressful conditions (i.e., high salinity and hypoxia), where vegetative reproduction and low competition result in mostly monotypic stands, with some differences in plant community influenced by flooding regime (described below). While there are several types of salt marshes in the Northern Gulf of Mexico (NGoM), ranging from low to high salt marshes and salt flats (Tiner, 2013), Spartina alterniflora–dominated salt marshes in the Coastal and Marine Ecological Classification Standard (CMECS) Low and Intermediate Salt Marsh …


Theorizing A Translanguaging Stance: Envisioning An Empowering Participatory Mathematics Education Juntos Con Emergent Bilingual Students, Luz A. Maldonado, Gladys Rueda Krause, Melissa Adams Corral Jan 2018

Theorizing A Translanguaging Stance: Envisioning An Empowering Participatory Mathematics Education Juntos Con Emergent Bilingual Students, Luz A. Maldonado, Gladys Rueda Krause, Melissa Adams Corral

Teaching and Learning Faculty Publications

We propose a translanguaging stance in the bilingual mathematics classroom defined by four elements: (1) Con respeto for other people’s ideas, leading to positive intellectual relations, (2) Con cariño, a commitment to the learning of others, (3) Como familia, working for the good of the classroom collective and for the benefit of individuals, and (4) Con acompañamiento, where teachers actively do math with their students. We propose a focus for the bilingual mathematics classroom and emergent bilingual students that emphasizes the importance of rehumanizing mathematics classrooms for all students and valuing their full linguistic repertoires.


Virtual Collaboration With Mobile Social Media In Multiple-Organization Projects, Zhaojun Yang, Jun Sun, Yali Zhang, Ying Wang Jan 2018

Virtual Collaboration With Mobile Social Media In Multiple-Organization Projects, Zhaojun Yang, Jun Sun, Yali Zhang, Ying Wang

Information Systems Faculty Publications

This study investigates the use of mobile social media as emerging collaboration tools by virtual teams. Based on the construal level theory, it develops a research model hypothesizes that collaboration tool effectiveness influence contextual performance and task performance through the mediation of procedure agreeability. In addition, geographic dispersion, team size and project duration serve as moderators as they reflect virtual collaboration complexity. Empirical findings support most hypothesized relationships. Theoretical and practical implications are discussed.


Pricing Of Games As A Service: An Analytical Model For Interactive Digital Services With Hedonic Properties, Tayfun Keskin Jan 2018

Pricing Of Games As A Service: An Analytical Model For Interactive Digital Services With Hedonic Properties, Tayfun Keskin

Information Systems Faculty Publications

This study explores optimal pricing strategies in games and other interactive digital goods under incomplete information, when bundling is an option. Drawing from research on the pricing of information goods, we propose a pattern of optimal pricing strategies in which hedonic characteristics affect the utility of interactive digital goods and services. This is a new approach to games, to treat them as a service to determine pricing strategies. Findings reveal that there is an optimal pricing solution for firms in the gaming industry. This finding holds both in bundling and non-bundling cases. Utilizing analytical modeling methodology, we propose pricing-inspired business …


Identification Of Chemical Compounds That Inhibit The Function Of Histidyl-Trna Synthetase From Pseudomonas Aeruginosa, Yanmei Hu, Stephanie O. Palmer, Sara Robles, Tahyra Resto, Frank Dean, James M. Bullard Jan 2018

Identification Of Chemical Compounds That Inhibit The Function Of Histidyl-Trna Synthetase From Pseudomonas Aeruginosa, Yanmei Hu, Stephanie O. Palmer, Sara Robles, Tahyra Resto, Frank Dean, James M. Bullard

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

Pseudomonas aeruginosa histidyl-tRNA synthetase (HisRS) was selected as a target for antibiotic drug development. The HisRS protein was overexpressed in Escherichia coli and kinetically evaluated. The KM values for interaction of HisRS with its three substrates, histidine, ATP, and tRNAHis, were 37.6, 298.5, and 1.5 μM, while the turnover numbers were 8.32, 16.8, and 0.57 s-1, respectively. A robust screening assay was developed, and 800 natural products and 890 synthetic compounds were screened for inhibition of activity. Fifteen compounds with inhibitory activity were identified, and the minimum inhibitory concentration (MIC) was determined for each against a panel of nine pathogenic …


Block Copolymer Elastomer With Graphite Filler: Effect Of Processing Conditions And Silane Coupling Agent On The Composite Properties, Denis M. Panaitescu, Raluca Augusta Gabor, Cristian Andi Nicolae, Anca Constantina Parau, Catalin Vitelaru, Valentin Raditoiu, Mircea Chipara Jan 2018

Block Copolymer Elastomer With Graphite Filler: Effect Of Processing Conditions And Silane Coupling Agent On The Composite Properties, Denis M. Panaitescu, Raluca Augusta Gabor, Cristian Andi Nicolae, Anca Constantina Parau, Catalin Vitelaru, Valentin Raditoiu, Mircea Chipara

Physics & Astronomy Faculty Publications

The control of morphology and interface in poly(styrene-ethylene/butylene-styrene) (SEBS) composites with graphitic fillers is extremely important for the design of piezoresistive sensors for body motion or flexible temperature sensors. The effects of a high amount of graphite (G) and silane coupling agent on the morphology and properties of SEBS composites with anisotropic mechanical properties are reported. The physical and chemical bonding of silane to both G and SEBS surface was proved by EDX and TGA results; this improved interface influenced both the thermal and mechanical properties of the composite. The vinyltriethoxysilane (VS) promoted the formation of char residue and, being …


Exchanging Deficit For Affordance: Developing Preservice Teachers’ Capacity To See Emergent Bilingual Students’ Resources, Aaron T. Wilson, Hyung Won Kim, M. Alejandra Sorto Jan 2018

Exchanging Deficit For Affordance: Developing Preservice Teachers’ Capacity To See Emergent Bilingual Students’ Resources, Aaron T. Wilson, Hyung Won Kim, M. Alejandra Sorto

School of Mathematical & Statistical Sciences Faculty Publications

We present a Scholarship of Teaching and Learning (SoTL) research project aimed at helping pre-service teachers to grasp the importance of their emergent bilingual students' bilingualism and cultural backgrounds as resources to serve them in apprehending mathematics instruction and explaining their mathematics to others.


Reactive Oxygen Species Generation In Human Cells By A Novel Magnetic Resonance Imaging Contrast Agent, Li Wang, Eric Lin, Mary J. Johansen, Timothy Madden, Edward Felix, Karen S. Martirosyan, Steven J. Frank Jan 2018

Reactive Oxygen Species Generation In Human Cells By A Novel Magnetic Resonance Imaging Contrast Agent, Li Wang, Eric Lin, Mary J. Johansen, Timothy Madden, Edward Felix, Karen S. Martirosyan, Steven J. Frank

Physics & Astronomy Faculty Publications

The novel positive-contrast magnetic resonance imaging (MRI) marker C4 consists of an aqueous solution of cobalt chloride (CoCl 2 ) complexed with the chelator N-acetylcysteine (NAC). We evaluated whether the presence of C4 or its components would produce reactive oxygen species (ROS, including hydroxyl, peroxyl, or other reactive oxygen species) in cultured cells. Human cancer or normal cells were incubated with 1% (w/v) CoCl 2 ·6H 2 O or 2% NAC or a combination of both (1% CoCl 2 ·6H 2 O: 2% NAC in an aqueous solution, abbreviated as Co: NAC) in the presence or absence of H 2 …


Toxicity Evaluation Of A Novel Magnetic Resonance Imaging Marker Cocl2-N-Acetylcysteine In Rats, Li Wang, Mihai Gagea, Karen S. Martirosyan, Mary Johansen, Timothy Madden, Lisa Norberg, Kirk S. Culotta, Steven J. Frank Jan 2018

Toxicity Evaluation Of A Novel Magnetic Resonance Imaging Marker Cocl2-N-Acetylcysteine In Rats, Li Wang, Mihai Gagea, Karen S. Martirosyan, Mary Johansen, Timothy Madden, Lisa Norberg, Kirk S. Culotta, Steven J. Frank

Physics & Astronomy Faculty Publications

C4 (cobalt dichloride-N-acetylcysteine [1% CoCl 2 :2% NAC]) is a novel magnetic resonance imaging contrast marker that facilitates visualization of implanted radioactive seeds in cancer brachytherapy. We evaluated the toxicity of C4. Rats were assigned to control (0% CoCl 2 :NAC), low-dose (0.1% CoCl 2 :2% NAC), reference-dose (C4), and high-dose (10% CoCl 2 :2% NAC) groups. Agent was injected into the left quadriceps femoris muscle of the rats. Endpoints were organ and body weights, hematology, and serum chemistry and histopathologic changes of tissues at 48 hours and 28 and 63 days after dosing. Student's t tests were used. No …


The Origin Of The First Neutron Star - Neutron Star Merger, K. Belczynski, A. Askar, M. Arca-Sedda, M. Chruslinska, M. Donnari, M. Giersz, M. Benacquista, R. Spurzem, D. Jin, G. Wiktorowicz, D. Belloni Jan 2018

The Origin Of The First Neutron Star - Neutron Star Merger, K. Belczynski, A. Askar, M. Arca-Sedda, M. Chruslinska, M. Donnari, M. Giersz, M. Benacquista, R. Spurzem, D. Jin, G. Wiktorowicz, D. Belloni

Physics & Astronomy Faculty Publications

The first neutron star-neutron star (NS-NS) merger was discovered on August 17, 2017 through gravitational waves (GW170817) and followed with electromagnetic observations. This merger was detected in an old elliptical galaxy with no recent star formation. We perform a suite of numerical calculations to understand the formation mechanism of this merger. We probe three leading formation mechanisms of double compact objects: classical isolated binary star evolution, dynamical evolution in globular clusters, and nuclear cluster formation to test whether they are likely to produce NS-NS mergers in old host galaxies. Our simulations with optimistic assumptions show current NS-NS merger rates at …


Many Paths Toward Discovery: A Module For Teaching How Science Works, Rebecca M. Price, Kathryn E. Perez Jan 2018

Many Paths Toward Discovery: A Module For Teaching How Science Works, Rebecca M. Price, Kathryn E. Perez

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

Improving students' understanding of how science works requires explicit instruction. Here, we test the efficacy of a module based on two previously published activities (the "Cube Puzzle" and the case study "Asteroids and Dinosaurs") that teach how science works to college science majors. Students also use the How Science Works Flowchart from Understanding Science (http://undsci.berkeley. edu/) to reflect on these activities. To assess the efficacy of this module, we asked students to illustrate the process of science before and after the intervention. After the intervention, students' diagrams were significantly more complex and nonlinear. Students also incorporated more social aspects of …


Identification And Mitigation Of Narrow Spectral Artifacts That Degrade Searches For Persistent Gravitational Waves In The First Two Observing Runs Of Advanced Ligo, P. B. Covas, A. Effler, E. Goetz, P. M. Meyers, A. Neunzert, M. Oliver, B. L. Pearlstone, Volker Quetschke, Karla E. Ramirez, Darkhan Tuyenbayev Jan 2018

Identification And Mitigation Of Narrow Spectral Artifacts That Degrade Searches For Persistent Gravitational Waves In The First Two Observing Runs Of Advanced Ligo, P. B. Covas, A. Effler, E. Goetz, P. M. Meyers, A. Neunzert, M. Oliver, B. L. Pearlstone, Volker Quetschke, Karla E. Ramirez, Darkhan Tuyenbayev

Physics & Astronomy Faculty Publications

Searches are under way in Advanced LIGO and Virgo data for persistent gravitational waves from continuous sources, e.g. rapidly rotating galactic neutron stars, and stochastic sources, e.g. relic gravitational waves from the Big Bang or superposition of distant astrophysical events such as mergers of black holes or neutron stars. These searches can be degraded by the presence of narrow spectral artifacts (lines) due to instrumental or environmental disturbances. We describe a variety of methods used for finding, identifying and mitigating these artifacts, illustrated with particular examples. Results are provided in the form of lists of line artifacts that can safely …


Kaposi Sarcoma Incidence In Females Is Nearly Four-Fold Higher In The Lower Rio Grande Valley Compared To The Texas Average, Wendy Innis-Whitehouse, Xiaohui Wang, Nicolas Restrepo, Carlos Salas, Katia Moreno, Alvaro Restrepo, Megan Keniry Jan 2018

Kaposi Sarcoma Incidence In Females Is Nearly Four-Fold Higher In The Lower Rio Grande Valley Compared To The Texas Average, Wendy Innis-Whitehouse, Xiaohui Wang, Nicolas Restrepo, Carlos Salas, Katia Moreno, Alvaro Restrepo, Megan Keniry

School of Medicine Publications

The Lower Rio Grande Valley (LRGV) is located on U.S.-Mexican border with a population that is 90% Hispanic[1]. Comprised of Hidalgo, Cameron, Starr and Willacy counties, this region has the highest poverty rate and one of the highest incidences of Type 2 diabetes in the United States[2],[3],[4]. Previous studies demonstrated a high prevalence of Human Herpes Virus 8 (HHV8) in the LRGV[5],[6],[7]. HHV8 infection has been causally linked to Kaposi Sarcoma (KS)[8]. Here, we retrospectively examine the incidence of KS in the LRGV in a set of HIV-negative Hispanic patients. Strikingly, the incidence of KS was higher in LRGV women …


Linear Stability Analysis With Solution Patterns Due To Varying Thermal Diffusivity For A Convective Flow In A Porous Medium, Dambaru Bhatta Jan 2018

Linear Stability Analysis With Solution Patterns Due To Varying Thermal Diffusivity For A Convective Flow In A Porous Medium, Dambaru Bhatta

School of Mathematical & Statistical Sciences Faculty Publications

Here we investigate the effect of the vertical rate of change in thermal diffusivity due to a hydrothermal convective flow in a horizontal porous medium. The continuity equation, the heat equation and the momentum-Darcy equation constitute the governing system for the flow in a porous medium. Assuming a vertically varying basic state, we derive the linear system and from this linear system, we compute the critical Rayleigh and wave numbers. Using fourth-order Runge-Kutta and shooting methods, we obtain the marginal stability curves and linear solutions to analyze the solution pattern for different diffusivity parameters.


The Development Of Secondary Mathematics Teachers’ Pedagogical Identities In The Social Context Of Classroom Interactions, Hyung Won Kim Jan 2018

The Development Of Secondary Mathematics Teachers’ Pedagogical Identities In The Social Context Of Classroom Interactions, Hyung Won Kim

School of Mathematical & Statistical Sciences Faculty Publications

Research demonstrates a disjuncture between the practices encouraged by teacher education programs and what teachers actually do in the classroom. It also informs us that the cognitive and social characteristics of individual teachers such as their attitudes, beliefs and knowledge contribute to their classroom practices. This qualitative study investigates how the teacher identity of mathematics teachers – the person’s sense of who he/she is as a mathematics teacher – is related to the disjuncture between encouraged and actual classroom practices. Specifically, the study looks into how mathematics teachers form their teaching practices in the social context of their classroom interactions, …


Effect Of Non-Hermiticity On Adiabatic Elimination In Coupled Waveguides, Rahman Sharaf, M. Dehghani, Hamidreza Ramezani Jan 2018

Effect Of Non-Hermiticity On Adiabatic Elimination In Coupled Waveguides, Rahman Sharaf, M. Dehghani, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

We investigate the influence of non-Hermiticity on the adiabatic elimination in coupled waveguides.We show that although the total norm of the system is not conserved in parity-time symmetric phase, the dark state intensity remains constant. However, in broken phase the eliminated waveguide loses its darkness, i.e., its field amplitude starts increasing. In both exact and broken phases, the effective Hamiltonian derived from the adiabatic elimination condition describes the dynamics of all states except the dark state. Specifically, it cannot predict the amplification in the intensity of the dark state. Our results can strengthen the control of the dynamics in cavities …


Expeditious Green Synthesis Of Versatile Organic Compounds By Diverse Methods, Bimal K. Banik Jan 2018

Expeditious Green Synthesis Of Versatile Organic Compounds By Diverse Methods, Bimal K. Banik

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

Synthesis of organic compounds requires organic solvents and reagents to promote them. Very often, toxic solvents are used for this purpose. Many organic reactions require molar proportion of reactants and reagents to accomplish the goal. Some reactions require longer reaction times and produce products without control of stereochemistry. Therefore, development of facile and effective organic reactions under environmentally friendly conditions is necessary. In this perspective, several reactions are discussed that are performed by microwave-induced reactions, catalytic procedures, in the absence of any solvents, one-pot method and in water. Important reactions are chosen to investigate the feasibility of conducting these reactions …


Synthesis Of Heterocycles Through Beta Lactams Ring Rupture, Bimal K. Banik Jan 2018

Synthesis Of Heterocycles Through Beta Lactams Ring Rupture, Bimal K. Banik

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

Many Beta lactams are widely used as medicines. The 4-membered ring present in the beta lactams is under strain and therefore, it can undergo cleavage reactions to diverse compounds. Chemical manipulation of the resulting products affords numerous molecules of interest. In this perspective, some examples developed at our laboratory are discussed


Versatile Catalytic Transfer Hydrogenations In Organic Synthesis, Bimal K. Banik, Khaled J. Barakat, Maghar S. Manhas Jan 2018

Versatile Catalytic Transfer Hydrogenations In Organic Synthesis, Bimal K. Banik, Khaled J. Barakat, Maghar S. Manhas

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

Catalytic transfer hydrogenation reactions are extremely useful in organic synthesis. We have investigated numerous reactions with ammonium formate (and other hydrogen gas donor) and 10% Pd/C successfully without using hydrogen gas. The reactions are very fast and produced products with high yields. Reduction of unsaturated groups, hydrogenolysis, reductive bond cleavage, allylic deacetoxylation, and dehalogenation are conducted using this method. In some instances, useful selectivity of reactions is observed. Most of the reactions are investigated with β-lactams as the substrates.


Stereoselectivity Of Phthalimido Β-Lactams Formation: Synthesis Of 3-Amino Β-Lactams Through A Facile Deprotection Reaction, Armando Paniagua, Ram Naresh Yadav, Sunena Chandra, Bimal K. Banik Jan 2018

Stereoselectivity Of Phthalimido Β-Lactams Formation: Synthesis Of 3-Amino Β-Lactams Through A Facile Deprotection Reaction, Armando Paniagua, Ram Naresh Yadav, Sunena Chandra, Bimal K. Banik

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

Synthesis of amino β-lactams is a crucial objective because of the medicinal properties associated with them and the products derived from of them. Stereocontrolled synthesis of phthalimido β-lactams is performed and cis and trans-phthalimido β-lactams are deprotected with ethylene diamine (and other reagents) to amino β-lactams of diverse structures in excellent yield. This reaction is also conducted under solventless conditions to afford identical products.


Key Enzymes In Cancer: Mechanism Of Action And Inhibition With Anticancer Agents, Debasish Bandyopadhyay, Gabriel Lopez, Stephanie Cantu, Samantha Balboa, Annabel Garcia, Christina Silva, Diandra Valdes Jan 2018

Key Enzymes In Cancer: Mechanism Of Action And Inhibition With Anticancer Agents, Debasish Bandyopadhyay, Gabriel Lopez, Stephanie Cantu, Samantha Balboa, Annabel Garcia, Christina Silva, Diandra Valdes

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

Several enzymes play significant role in different stages of cancer including proliferation, invasion, metastasis and angiogenesis. Mechanism of actions of a few key enzymes along with their inhibitors have been discussed with particular attentation to riboneucleotide reductase, thymidylate synthease, topoisomerase II, interleukins, cell survival proteins and aminopeptidase N.


What Is Teacher Agency?, Alcione N. Ostorga Jan 2018

What Is Teacher Agency?, Alcione N. Ostorga

Bilingual and Literacy Studies Faculty Publications

No abstract provided.


Stable Solution To L 2,1-Based Robust Inductive Matrix Completion And Its Application In Linking Long Noncoding Rnas To Human Diseases, Ashis Kumer Biswas, Dong-Chul Kim, Mingon Kang, Chris Ding, Jean X. Gao Dec 2017

Stable Solution To L 2,1-Based Robust Inductive Matrix Completion And Its Application In Linking Long Noncoding Rnas To Human Diseases, Ashis Kumer Biswas, Dong-Chul Kim, Mingon Kang, Chris Ding, Jean X. Gao

Computer Science Faculty Publications

Backgrounds

A large number of long intergenic non-coding RNAs (lincRNAs) are linked to a broad spectrum of human diseases. The disease association with many other lincRNAs still remain as puzzle. Validation of such links between the two entities through biological experiments are expensive. However, a plethora lincRNA-data are available now, thanks to the High Throughput Sequencing (HTS) platforms, Genome Wide Association Studies (GWAS), etc, which opens the opportunity for cutting-edge machine learning and data mining approaches to extract meaningful relationships among lincRNAs and diseases. However, there are only a few in silico lincRNA-disease association inference tools available to date, and …


Pulsar J1411+2551: A Low-Mass Double Neutron Star System, J. G. Martinez, K. Stovall, P. C.C. Freire, J. S. Deneva, T. M. Tauris, A. Ridolfi, N. Wex, Fredrick Jenet, M. A. Mclaughlin, M. Bagchi Dec 2017

Pulsar J1411+2551: A Low-Mass Double Neutron Star System, J. G. Martinez, K. Stovall, P. C.C. Freire, J. S. Deneva, T. M. Tauris, A. Ridolfi, N. Wex, Fredrick Jenet, M. A. Mclaughlin, M. Bagchi

Physics & Astronomy Faculty Publications

In this work, we report the discovery and characterization of PSR J1411+2551, a new binary pulsar discovered in the Arecibo 327 MHz Drift Pulsar Survey. Our timing observations of the radio pulsar in the system span a period of about 2.5 years. This timing campaign allowed a precise measurement of its spin period (62.4 ms) and its derivative (9.6 ±0.7) ×10 -20 s s -1 ; from these, we derive a characteristic age of >9.1 Gyr and a surface magnetic field strength of < 2.6 ×10 9 G. These numbers indicate that this pulsar was mildly recycled by accretion of matter from the progenitor of the companion star. The system has an eccentric (e =0.17) 2.61 day orbit. This eccentricity allows a highly significant measurement of the rate of advance of periastron, . Assuming general relativity accurately describes the orbital motion, this implies a total system mass M =2.538 ±0.022 M o . The minimum companion mass is 0.92 M o and the maximum pulsar mass is 1.62 M o . The large companion mass and the orbital eccentricity suggest that PSR J1411+2551 is a double neutron star system; the lightest known to date including the DNS merger GW170817. Furthermore, the relatively low orbital eccentricity and small proper motion limits suggest that the second supernova had a relatively small associated kick; this and the low system mass suggest that it was an ultra-stripped supernova.


Gw170608: Observation Of A 19 Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov Dec 2017

Gw170608: Observation Of A 19 Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

On 2017 June 8 at 02:01:16.49 UTC, a gravitational-wave (GW) signal from the merger of two stellar-mass blackholes was observed by the two Advanced Laser Interferometer Gravitational-Wave Observatory detectors with anetwork signal-to-noise ratio of 13. This system is the lightest black hole binary so far observed, with componentmasses of 12+7-2M⊙7+2-2 (90% credible intervals). These lie in the range of measured black hole masses inlow-mass X-ray binaries, thus allowing us to compare black holes detected through GWs with electromagneticobservations. The source's luminosity distance is 340+140-140corresponding to redshift -0.07+0.03003. We verify thatthe signal waveform is consistent with the predictions of general relativity.


First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov Dec 2017

First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars …


First Low-Frequency Einstein@Home All-Sky Search For Continuous Gravitational Waves In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Teviet Creighton, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov Dec 2017

First Low-Frequency Einstein@Home All-Sky Search For Continuous Gravitational Waves In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Teviet Creighton, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the first Advanced LIGO observing run. This search investigates the low frequency range of Advanced LIGO data, between 20 and 100 Hz, much of which was not explored in initial LIGO. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to a sensitivity depth of 48.7 …


Des And Tdes Performance Evaluation For Non-Pipelined And Pipelined Implementations In Vhdl Using The Cyclone Ii Fpga Technology, Edni Del Rosal Dec 2017

Des And Tdes Performance Evaluation For Non-Pipelined And Pipelined Implementations In Vhdl Using The Cyclone Ii Fpga Technology, Edni Del Rosal

Theses and Dissertations

Two ongoing issues that engineers must face in the new era of data analytics are performance and security. Field Programmable Gate Arrays (FPGAs) offer a new solution for optimizing the performance of applications while the Data Encryption Standard (DES) and the Triple Data Encryption Standard (TDES) offer a mean to secure information. In this thesis we present a Non-Pipelined and Pipelined, in Electronic Code Book (EBC) mode, implementations in VHDL of these two commonly utilized cryptography schemes. Using Altera Cyclone II FPGA as our platform, we design and verify the implementations with the EDA tools provided by Altera. We gather …