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2020

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Tennessee State University

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Full-Text Articles in Physical Sciences and Mathematics

Physical Parameters Of The Multiplanet Systems Hd 106315 And Gj 9827*†, Molly R. Kosiarek, David A. Berardo, Ian J. M. Crossfield, Cesar Laguna, Caroline Piaulet, Joseph M. Akana Murphy, Steve B. Howell, Gregory W. Henry, Howard Isaacson, Benjamin Fulton, Lauren M. Weiss, Erik A. Petigura, Aida Behmard, Lea A. Hirsch, Johanna Teske, Jennifer A. Burt, Sean M. Mills, Ashley Chontos, Teo Močnik, Andrew W. Howard, Michael Werner, John H. Livingston, Jessica Krick, Charles Beichman, Varoujan Gorjian, Laura Kreidberg, Caroline Morley, Jessie L. Christiansen, Farisa Y. Morales, Nicholas J. Scott, Jeffrey D. Crane, Sharon Xuesong Wang, Stephen A. Shectman, Lee J. Rosenthal, Samuel K. Grunblatt, Ryan A. Rubenzahl, Paul A. Dalba, Steven Giacalone, Chiara Dane Villanueva, Qingtian Liu, Fei Dai, Michelle L. Hill, Malena Rice, Stephen R. Kane, Andrew W. Mayo Dec 2020

Physical Parameters Of The Multiplanet Systems Hd 106315 And Gj 9827*†, Molly R. Kosiarek, David A. Berardo, Ian J. M. Crossfield, Cesar Laguna, Caroline Piaulet, Joseph M. Akana Murphy, Steve B. Howell, Gregory W. Henry, Howard Isaacson, Benjamin Fulton, Lauren M. Weiss, Erik A. Petigura, Aida Behmard, Lea A. Hirsch, Johanna Teske, Jennifer A. Burt, Sean M. Mills, Ashley Chontos, Teo Močnik, Andrew W. Howard, Michael Werner, John H. Livingston, Jessica Krick, Charles Beichman, Varoujan Gorjian, Laura Kreidberg, Caroline Morley, Jessie L. Christiansen, Farisa Y. Morales, Nicholas J. Scott, Jeffrey D. Crane, Sharon Xuesong Wang, Stephen A. Shectman, Lee J. Rosenthal, Samuel K. Grunblatt, Ryan A. Rubenzahl, Paul A. Dalba, Steven Giacalone, Chiara Dane Villanueva, Qingtian Liu, Fei Dai, Michelle L. Hill, Malena Rice, Stephen R. Kane, Andrew W. Mayo

Information Systems and Engineering Management Research Publications

HD 106315 and GJ 9827 are two bright, nearby stars that host multiple super-Earths and sub-Neptunes discovered by K2 that are well suited for atmospheric characterization. We refined the planets' ephemerides through Spitzer transits, enabling accurate transit prediction required for future atmospheric characterization through transmission spectroscopy. Through a multiyear high-cadence observing campaign with Keck/High Resolution Echelle Spectrometer and Magellan/Planet Finder Spectrograph, we improved the planets' mass measurements in anticipation of Hubble Space Telescope transmission spectroscopy. For GJ 9827, we modeled activity-induced radial velocity signals with a Gaussian process informed by the Calcium II H&K lines in order to more accurately …

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Armada. I. Triple Companions Detected In B-Type Binaries Α Del And Ν Gem, Tyler Gardner, John D. Monnier, Francis C. Fekel, Gail Schaefer, Keith J. C. Johnson, Jean-Baptiste Le Bouquin, Stefan Kraus, Narsireddy Anugu, Benjamin R. Setterholm, Aaron Labdon, Claire L. Davies, Cyprien Lanthermann, Jacob Ennis, Michael Ireland, Kaitlin M. Kratter, Theo Ten Brummelaar, Judit Sturmann, Laszlo Sturmann, Chris Farrington, Douglas R. Gies, Robert Klement, Fred C. Adams Dec 2020

Armada. I. Triple Companions Detected In B-Type Binaries Α Del And Ν Gem, Tyler Gardner, John D. Monnier, Francis C. Fekel, Gail Schaefer, Keith J. C. Johnson, Jean-Baptiste Le Bouquin, Stefan Kraus, Narsireddy Anugu, Benjamin R. Setterholm, Aaron Labdon, Claire L. Davies, Cyprien Lanthermann, Jacob Ennis, Michael Ireland, Kaitlin M. Kratter, Theo Ten Brummelaar, Judit Sturmann, Laszlo Sturmann, Chris Farrington, Douglas R. Gies, Robert Klement, Fred C. Adams

Information Systems and Engineering Management Research Publications

Ground-based optical long-baseline interferometry has the power to measure the orbits of close binary systems at ∼10 μas precision. This precision makes it possible to detect "wobbles" in the binary motion due to the gravitational pull from additional short-period companions. We started the ARrangement for Micro-Arcsecond Differential Astrometry (ARMADA) survey with the Michigan Infra-Red Combiner (MIRC)/MIRC-X instrument at the Center for High Angular Resoloution Astronomy (CHARA) array for the purpose of detecting giant planets and stellar companions orbiting individual stars in binary systems. We describe our observations for the survey, and introduce the wavelength calibration scheme that delivers precision at …

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Melanogenesis, Its Regulatory Process, And Insights On Biomedical, Biotechnological, And Pharmacological Potentials Of Melanin As Antiviral Biochemical, Toluwase Hezekiah Fatoki, Omodele Ibraheem, Catherine Joke Adeseko, Boluwatife Lawrence Afolabi, Daniel Uwaremhevho Momodu, David Morakinyo Sanni, Jesupemi Mercy Enibukun, Ibukun Oladejo Ogunyemi, Akinwunmi Oluwaseun Adeoye, Harriet U. Ugboko, Amoge Chidinma Ogu, Abiodun Samuel Oyedele, Adejoju Omodolapo Adedara, Abiodun Joseph Jimoh, Oluwakemi Ruth Ogundana, Oritsetimeyin Eworitse Ebosa Dec 2020

Melanogenesis, Its Regulatory Process, And Insights On Biomedical, Biotechnological, And Pharmacological Potentials Of Melanin As Antiviral Biochemical, Toluwase Hezekiah Fatoki, Omodele Ibraheem, Catherine Joke Adeseko, Boluwatife Lawrence Afolabi, Daniel Uwaremhevho Momodu, David Morakinyo Sanni, Jesupemi Mercy Enibukun, Ibukun Oladejo Ogunyemi, Akinwunmi Oluwaseun Adeoye, Harriet U. Ugboko, Amoge Chidinma Ogu, Abiodun Samuel Oyedele, Adejoju Omodolapo Adedara, Abiodun Joseph Jimoh, Oluwakemi Ruth Ogundana, Oritsetimeyin Eworitse Ebosa

Chemistry Student Research

Melanin is s most widely distributed pigment and is found in bacteria, fungi, plants, and animals. Melanogenesis is under complex regulatory control by multiple agents interacting through pathways activated by hormonal and receptor-dependent and -independent mechanisms. There are about 20 genes that are involved in the biochemical pathway of melanogenesis and its regulation, which include: tyrosinase, microphthalmia-associated transcription factor, melanocortin1 receptor, adenylate cyclase, protein kinase A. Human melanogenesis regulatory proteins such as MAPK1, CREB3, and CREBP, have binary interaction with the protein of herpesvirus, hepatitis C virus, Human immunodeficiency virus type 1, Simian virus 40, and Human adenovirus A and …

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Multiple Constraints Cause Positive And Negative Feedbacks Limiting Grassland Soil Co2 Efflux Under Co2 Enrichment, Philip A. Fay, Dafeng Hui, Robert B. Jackson, Harold P. Collins, Lara G. Reichmann, Michael J. Aspinwall, Virginia L. Jin, Albina R. Khasanova, Robert W. Heckman, H. Wayne Polley Dec 2020

Multiple Constraints Cause Positive And Negative Feedbacks Limiting Grassland Soil Co2 Efflux Under Co2 Enrichment, Philip A. Fay, Dafeng Hui, Robert B. Jackson, Harold P. Collins, Lara G. Reichmann, Michael J. Aspinwall, Virginia L. Jin, Albina R. Khasanova, Robert W. Heckman, H. Wayne Polley

Biology Faculty Research

Understanding ecosystem carbon-cycling responses to atmospheric CO2 enrichment is critical to preserve biodiversity and maintain vital ecosystem services in grasslands impacted by global change. We conducted an 8-y experiment enriching CO2 concentrations from preindustrial to midtwenty-first century levels on grassland plant communities on upland, lowland, and alluvial soils. CO2 enrichment increased the CO2 efflux from soils to atmosphere in amounts depending on whether the dominant limitation was CO2 or feedbacks (net positive or negative) from soil moisture and plant species turnover. These findings highlight how multiple concurrent limitations, not single limitations in sequence, regulate the …

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Adaptive Ensemble Of Classifiers With Regularization For Imbalanced Data Classification, Chen Wang, Chengyuan Deng, Zhoulu Yu, Dafeng Hui, Xiaofeng Gong, Ruisen Luo Dec 2020

Adaptive Ensemble Of Classifiers With Regularization For Imbalanced Data Classification, Chen Wang, Chengyuan Deng, Zhoulu Yu, Dafeng Hui, Xiaofeng Gong, Ruisen Luo

Biology Faculty Research

The dynamic ensemble selection of classifiers is an effective approach for processing label-imbalanced data classifications. However, such a technique is prone to overfitting, owing to the lack of regularization methods and the dependence on local geometry of data. In this study, focusing on binary imbalanced data classification, a novel dynamic ensemble method, namely adaptive ensemble of classifiers with regularization (AER), is proposed, to overcome the stated limitations. The method solves the overfitting problem through a new perspective of implicit regularization. Specifically, it leverages the properties of stochastic gradient descent to obtain the solution with the minimum norm, thereby achieving regularization; …

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Expres. Ii. Searching For Planets Around Active Stars: A Case Study Of Hd 101501, Samuel H. C. Cabot, Rachael M. Roettenbacher, Gregory W. Henry, Lily Zhao, Robert O. Harmon, Debra A. Fischer, John M. Brewer, Joe Llama, Ryan R. Petersburg, Andrew E. Szymkowiak Dec 2020

Expres. Ii. Searching For Planets Around Active Stars: A Case Study Of Hd 101501, Samuel H. C. Cabot, Rachael M. Roettenbacher, Gregory W. Henry, Lily Zhao, Robert O. Harmon, Debra A. Fischer, John M. Brewer, Joe Llama, Ryan R. Petersburg, Andrew E. Szymkowiak

Information Systems and Engineering Management Research Publications

By controlling instrumental errors to below 10 cm s−1, the EXtreme PREcision Spectrograph (EXPRES) allows for a more insightful study of photospheric velocities that can mask weak Keplerian signals. Gaussian processes (GP) have become a standard tool for modeling correlated noise in radial velocity data sets. While GPs are constrained and motivated by physical properties of the star, in some cases they are still flexible enough to absorb unresolved Keplerian signals. We apply GP regression to EXPRES radial velocity measurements of the 3.5 Gyr old chromospherically active Sun-like star, HD 101501. We obtain tight constraints on the stellar rotation period …

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Survey On Deep Neural Networks In Speech And Vision Systems, M. Alam, Manar D. Samad, Lasitha Vidyaratne, ‪Alexander Glandon, Khan M. Iftekharuddin Dec 2020

Survey On Deep Neural Networks In Speech And Vision Systems, M. Alam, Manar D. Samad, Lasitha Vidyaratne, ‪Alexander Glandon, Khan M. Iftekharuddin

Computer Science Faculty Research

This survey presents a review of state-of-the-art deep neural network architectures, algorithms, and systems in speech and vision applications. Recent advances in deep artificial neural network algorithms and architectures have spurred rapid innovation and development of intelligent speech and vision systems. With availability of vast amounts of sensor data and cloud computing for processing and training of deep neural networks, and with increased sophistication in mobile and embedded technology, the next-generation intelligent systems are poised to revolutionize personal and commercial computing. This survey begins by providing background and evolution of some of the most successful deep learning models for intelligent …

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A Collage Of Small Planets From The Lick–Carnegie Exoplanet Survey: Exploring The Super-Earth And Sub-Neptune Mass Regime, Jennifer Burt, Fabo Feng, Bradford Holden, Eric E. Mamajek, Chelsea X. Huang, Mickey M. Rosentha, Songhu Wang, R. Paul Butler, Steve S. Vogt, Gregory Laughlin, Gregory W. Henry, Johanna K. Teske, Sharon X. Wang, Jeffrey D. Crane, Steve A. Shectman Dec 2020

A Collage Of Small Planets From The Lick–Carnegie Exoplanet Survey: Exploring The Super-Earth And Sub-Neptune Mass Regime, Jennifer Burt, Fabo Feng, Bradford Holden, Eric E. Mamajek, Chelsea X. Huang, Mickey M. Rosentha, Songhu Wang, R. Paul Butler, Steve S. Vogt, Gregory Laughlin, Gregory W. Henry, Johanna K. Teske, Sharon X. Wang, Jeffrey D. Crane, Steve A. Shectman

Information Systems and Engineering Management Research Publications

Analysis of new precision radial velocity (RV) measurements from the Lick Automated Planet Finder and Keck HIRES has yielded the discovery of three new exoplanet candidates orbiting the nearby stars HD 190007 and HD 216520. We also report new velocities from the APF and the Planet Finder Spectrograph and updated orbital fits for the known exoplanet host stars GJ 686 and HD 180617. Of the newly discovered planets, HD 190007 b has a period of P = 11.72 days, an RV semiamplitude of K = 5.64 ± 0.55 m s−1, a minimum mass of Mpl = 16.46 ± 1.66 M⊕, …

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The M Supergiant High-Mass X-Ray Binary 4u 1954+31, Kenneth H. Hinkle, Thomas Lebzelter, Francis C. Fekel, Oscar Straniero, Richard Joyce, Lisa Prato, Nicole Karnath, Nolan Habel Nov 2020

The M Supergiant High-Mass X-Ray Binary 4u 1954+31, Kenneth H. Hinkle, Thomas Lebzelter, Francis C. Fekel, Oscar Straniero, Richard Joyce, Lisa Prato, Nicole Karnath, Nolan Habel

Information Systems and Engineering Management Research Publications

The X-ray binary 4U 1954+31 has been classified as a low-mass X-ray binary containing an M giant and a neutron star (NS). It has also been included in the rare class of X-ray symbiotic binaries. The Gaia parallax, infrared colors, spectral type, abundances, and orbital properties of the M star demonstrate that the cool star in this system is not a low-mass giant but a high-mass M supergiant. Thus, 4U 1954+31 is a high-mass X-ray binary (HMXB) containing a late-type supergiant. It is the only known binary system of this type. The mass of the M I is ${9}_{-2}^{+6}$ M⊙ …

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Multi-Year Incubation Experiments Boost Confidence In Model Projections Of Long-Term Soil Carbon Dynamics, Siyang Jian, Jianwei Li, Gangsheng Wang, Laurel A. Kluber, Christopher W. Schadt, Junyi Liang, Melanie A. Mayes Nov 2020

Multi-Year Incubation Experiments Boost Confidence In Model Projections Of Long-Term Soil Carbon Dynamics, Siyang Jian, Jianwei Li, Gangsheng Wang, Laurel A. Kluber, Christopher W. Schadt, Junyi Liang, Melanie A. Mayes

Agricultural and Environmental Sciences Faculty Research

Global soil organic carbon (SOC) stocks may decline with a warmer climate. However, model projections of changes in SOC due to climate warming depend on microbially-driven processes that are usually parameterized based on laboratory incubations. To assess how lab-scale incubation datasets inform model projections over decades, we optimized five microbially-relevant parameters in the Microbial-ENzyme Decomposition (MEND) model using 16 short-term glucose (6-day), 16 short-term cellulose (30-day) and 16 long-term cellulose (729-day) incubation datasets with soils from forests and grasslands across contrasting soil types. Our analysis identified consistently higher parameter estimates given the short-term versus long-term datasets. Implementing the short-term and …

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Potential Of Hemp (Cannabis Sativa L.) For Paired Phytoremediation And Bioenergy Production, Hanah T. Rheay, Emmanuel C. Omondi, Catherine E. Brewer Nov 2020

Potential Of Hemp (Cannabis Sativa L.) For Paired Phytoremediation And Bioenergy Production, Hanah T. Rheay, Emmanuel C. Omondi, Catherine E. Brewer

Agricultural and Environmental Sciences Faculty Research

Hemp (Cannabis sativa L.) is a multi-use crop that has been investigated for its potential use in phytoremediation of heavy metals, radionuclides, and organic contaminants, and as a feedstock for bioenergy production. A review of research literature indicates that hemp is a suitable crop for phytoremediation, and a competitive option for bioenergy. Coupling phytoremediation and bioenergy production from a single hemp crop is a potential solution to overcoming the economic constraints of phytoremediation projects. The current challenge is ensuring that the extracted contaminants are not introduced into the consumer marketplace. After several decades of limited research on hemp in the …

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Reduced Lignin Decomposition And Enhanced Soil Organic Carbon Stability By Acid Rain: Evidence From 13c Isotope And 13c Nmr Analyses, Jianping Wu, Qi Deng, Dafeng Hui, Xin Xiong, Huiling Zhang, Mengdi Zhao, Xuan Wang, Minghui Hu, Yongxian Su, Hongou Zhang, Guowei Chu, Deqiang Zhang Nov 2020

Reduced Lignin Decomposition And Enhanced Soil Organic Carbon Stability By Acid Rain: Evidence From 13c Isotope And 13c Nmr Analyses, Jianping Wu, Qi Deng, Dafeng Hui, Xin Xiong, Huiling Zhang, Mengdi Zhao, Xuan Wang, Minghui Hu, Yongxian Su, Hongou Zhang, Guowei Chu, Deqiang Zhang

Biology Faculty Research

Due to the emissions of air pollutants, acid rain in southern China poses a great threat to terrestrial ecosystems. However, its influences on ecological processes such as litter decomposition and soil organic carbon (SOC) accumulation are still not clear. The aim of this study was to understand the potential mechanisms of carbon sequestration change in response to long-term acid rain in a subtropical forest. A field experiment with simulated acid rain (SAR) treatment was conducted in a monsoon evergreen broadleaf forest in southern China. Four levels of SAR treatment were implemented by irrigating the plots with water of different pH …

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Access: Confirmation Of No Potassium In The Atmosphere Of Wasp-31b, Chima D. Mcgruder, Mercedes López-Morales, Néstor Espinoza, Benjamin V. Rackham, Dániel Apai, Andrés Jordán, David J. Osip, Munazza K. Alam, Alex Bixel, Jonathan J. Fortney, Gregory W. Henry, James Kirk, Nikole K. Lewis, Florian Rodler, Ian C. Weaver Oct 2020

Access: Confirmation Of No Potassium In The Atmosphere Of Wasp-31b, Chima D. Mcgruder, Mercedes López-Morales, Néstor Espinoza, Benjamin V. Rackham, Dániel Apai, Andrés Jordán, David J. Osip, Munazza K. Alam, Alex Bixel, Jonathan J. Fortney, Gregory W. Henry, James Kirk, Nikole K. Lewis, Florian Rodler, Ian C. Weaver

Information Systems and Engineering Management Research Publications

We present a new optical (400–950 nm) transmission spectrum of the hot Jupiter WASP-31b (M = 0.48 MJ; R = 1.54 RJ; P = 3.41 days), obtained by combining four transit observations. These transits were observed with IMACS on the Magellan Baade Telescope at Las Campanas Observatory as part of the ACCESS project. We investigate the presence of clouds/hazes in the upper atmosphere of this planet, as well as the contribution of stellar activity on the observed features. In addition, we search for absorption features of the alkali elements Na i and K i, with particular focus on K i, …

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Environmental Investigation Of Bio-Modification Of Steel Slag Through Microbially Induced Carbonate Precipitation, Junke Zhang, Peidong Su, Yadong Li, Lin Li Sep 2020

Environmental Investigation Of Bio-Modification Of Steel Slag Through Microbially Induced Carbonate Precipitation, Junke Zhang, Peidong Su, Yadong Li, Lin Li

Civil and Architectural Engineering Faculty Research

Steel slag (SS) is one of byproduct of steel manufacture industry. The environmental concerns of SS may limit their re-use in different applications. The goal of this study was to investigate the leaching behavior of metals from SS before and after treated by microbially induced carbonate precipitation (MICP). Toxicity characteristic leaching procedure, synthetic precipitation leaching procedure and water leaching tests were performed to evaluate the leaching behavior of major elements (Fe, Mg and Ca) and trace elements (Ba, Cu and Mn) in three scenarios. The concentrations of leaching metals increased with the content of SS. After it reached the peak …

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Lrg-Beasts: Ground-Based Detection Of Sodium And A Steep Optical Slope In The Atmosphere Of The Highly Inflated Hot-Saturn Wasp-21b, Lili Alderson, James Kirk, Mercedes López-Morales, Peter J. Wheatley, Ian Skillen, Gregory W. Henry, Chima Mcgruder, Matteo Brogi, Tom Louden, George King Aug 2020

Lrg-Beasts: Ground-Based Detection Of Sodium And A Steep Optical Slope In The Atmosphere Of The Highly Inflated Hot-Saturn Wasp-21b, Lili Alderson, James Kirk, Mercedes López-Morales, Peter J. Wheatley, Ian Skillen, Gregory W. Henry, Chima Mcgruder, Matteo Brogi, Tom Louden, George King

Information Systems and Engineering Management Research Publications

We present the optical transmission spectrum of the highly inflated Saturn-mass exoplanet WASP-21b, using three transits obtained with the ACAM instrument on the William Herschel Telescope through the LRG-BEASTS survey (Low Resolution Ground-Based Exoplanet Atmosphere Survey using Transmission Spectroscopy). Our transmission spectrum covers a wavelength range of 4635–9000 Å, achieving an average transit depth precision of 197 ppm compared to one atmospheric scale height at 246 ppm. We detect Na i absorption in a bin width of 30 Å  at >4σ confidence, which extends over 100 Å. We see no evidence of absorption from K i. Atmospheric retrieval analysis of …

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Vertical Distributions Of Soil Microbial Biomass Carbon: A Global Dataset, Tingting Sun, Yugang Wang, Dafeng Hui, Xin Jing, Wenting Feng Aug 2020

Vertical Distributions Of Soil Microbial Biomass Carbon: A Global Dataset, Tingting Sun, Yugang Wang, Dafeng Hui, Xin Jing, Wenting Feng

Biology Faculty Research

Soil microbial biomass carbon (SMBC) is important in regulating soil organic carbon (SOC) dynamics along soil profiles by mediating the decomposition and formation of SOC. The dataset (VDMBC) is about the vertical distributions of SOC, SMBC, and soil microbial quotient (SMQ = SMBC/SOC) and their relations to environmental factors across five continents. Data were collected from literature, with a total of 289 soil profiles and 1040 observations in different soil layers compiled. The associated environment data collectd include climate, ecosystem types, and edaphic factors. We developed this dataset by searching the Web of Sciene and the China National Knowledge Infrastructure …

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Effect Of Text Processing Steps On Twitter Sentiment Classification Using Word Embedding, Manar D. Samad, Nalin D. Khounviengxay, Megan A. Witherow Jul 2020

Effect Of Text Processing Steps On Twitter Sentiment Classification Using Word Embedding, Manar D. Samad, Nalin D. Khounviengxay, Megan A. Witherow

Computer Science Faculty Research

Processing of raw text is the crucial first step in text classification and sentiment analysis. However, text processing steps are often performed using off-the-shelf routines and pre-built word dictionaries without optimizing for domain, application, and context. This paper investigates the effect of seven text processing scenarios on a particular text domain (Twitter) and application (sentiment classification). Skip gram-based word embeddings are developed to include Twitter colloquial words, emojis, and hashtag keywords that are often removed for being unavailable in conventional literature corpora. Our experiments reveal negative effects on sentiment classification of two common text processing steps: 1) stop word removal …

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In Silico Investigation Of First-Pass Effect On Selected Small Molecule Excipients And Structural Dynamics Of P-Glycoprotein, Toluwase Hezekiah Fatoki, Omodele Ibraheem, Oladoja A. Awofisayo, Abiodun Samuel Oyedele, Olapade Samuel Akinlolu Jul 2020

In Silico Investigation Of First-Pass Effect On Selected Small Molecule Excipients And Structural Dynamics Of P-Glycoprotein, Toluwase Hezekiah Fatoki, Omodele Ibraheem, Oladoja A. Awofisayo, Abiodun Samuel Oyedele, Olapade Samuel Akinlolu

Chemistry Student Research

In this study, the interaction of selected pharmaceutical excipients on the function of P-glycoprotein (P-gp) and activity of 6 cytochrome P450 (CYP) isoforms were computationally investigated. At binding free energy cut-off value of −5.0 kcal/mol, the result showed possible modulatory or inhibitory effect by cethyl alcohol on CPY3A4 and P-gp; cetyltrimethyl-ammonium bromide (CTAB) on CYP1A2 and P-gp; dibutyl sebacate on CYP2C9, CYP2E1, and P-gp; sodium caprylate on CYP1A2 and CYP3A4; while most of the tested excipients have good interaction with the cytochromes and P-gp. The predicted pharmacokinetics provided possible inhibitors of the CYPs and P-gp and suggested that aspartame and …

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Expres. I. Hd 3651 As An Ideal Rv Benchmark, John M. Brewer, Debra A. Fischer, Ryan T. Blackman, Samuel H. C. Cabot, Allen B. Davis, Gregory Laughlin, Christopher Leet, J. M. Joel Ong, Ryan R. Petersburg, Andrew E. Szymkowiak, Lily L. Zhao, Gregory W. Henry, Joe Llama Jul 2020

Expres. I. Hd 3651 As An Ideal Rv Benchmark, John M. Brewer, Debra A. Fischer, Ryan T. Blackman, Samuel H. C. Cabot, Allen B. Davis, Gregory Laughlin, Christopher Leet, J. M. Joel Ong, Ryan R. Petersburg, Andrew E. Szymkowiak, Lily L. Zhao, Gregory W. Henry, Joe Llama

Information Systems and Engineering Management Research Publications

The next generation of exoplanet-hunting spectrographs should deliver up to an order of magnitude improvement in radial velocity (RV) precision over the standard 1 ${\rm{m}}\ {{\rm{s}}}^{-1}$ state-of-the-art spectrographs. This advance is critical for enabling the detection of Earth-mass planets around Sun-like stars. New calibration techniques such as laser frequency combs and stabilized etalons ensure that the instrumental stability is well characterized. However, additional sources of error include stellar noise, undetected short-period planets, and telluric contamination. To understand and ultimately mitigate error sources, the contributing terms in the error budget must be isolated to the greatest extent possible. Here, we introduce …

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Relationships Between Vegetation And Soil Seed Banks Along A Center-To-Edge Gradient On A Tropical Coral Island, Yao Huang, Hai Ren, Jun Wang, Nan Liu, Shuguang Jian, Hongyue Cai, Dafeng Hui, Qinfeng Guo Jul 2020

Relationships Between Vegetation And Soil Seed Banks Along A Center-To-Edge Gradient On A Tropical Coral Island, Yao Huang, Hai Ren, Jun Wang, Nan Liu, Shuguang Jian, Hongyue Cai, Dafeng Hui, Qinfeng Guo

Biology Faculty Research

Few studies have focused on the relationships between vegetation and soil seed banks on small islands. To better understand the pattern and regeneration potential of seed banks on tropical coral islands, we measured environmental factors and the species composition, and species richness of soil seed banks and vegetation along a gradient from the center to the edges on East Island in the South China Sea. The results showed that the similarity between the species composition of vegetation and seed banks increased from the center to the edge. In the center, species richness in both vegetation and seed banks was positively …

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Visual Orbits Of Spectroscopic Binaries With The Chara Array. Iii. Hd 8374 And Hd 24546, Kathryn V. Lester, Francis C. Fekel, Matthew W. Muterspaugh, Douglas R. Gies, Gail Schaefer, Chris D. Farrington, Zhao Guo, Rachel A. Matson, John D. Monnier, Theo A. Ten Brummelaar, Judit Sturmann, Samuel A. Weiss Jul 2020

Visual Orbits Of Spectroscopic Binaries With The Chara Array. Iii. Hd 8374 And Hd 24546, Kathryn V. Lester, Francis C. Fekel, Matthew W. Muterspaugh, Douglas R. Gies, Gail Schaefer, Chris D. Farrington, Zhao Guo, Rachel A. Matson, John D. Monnier, Theo A. Ten Brummelaar, Judit Sturmann, Samuel A. Weiss

Information Systems and Engineering Management Research Publications

We present the visual orbits of two long-period spectroscopic binary stars, HD 8374 and HD 24546, using interferometric observations acquired with the CHARA Array and the Palomar Testbed Interferometer. We also obtained new radial velocities from echelle spectra using the APO 3.5 m and Fairborn 2.0 m telescopes. By combining the visual and spectroscopic observations, we solve for the full, three-dimensional orbits and determine the stellar masses and distances to within 3% uncertainty. We then estimate the effective temperature and radius of each component star through Doppler tomography and spectral energy distribution analyses, in order to compare the observed stellar …

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The Hubble Space Telescope Pancet Program: An Optical To Infrared Transmission Spectrum Of Hat-P-32ab, Munazza K. Alam, Mercedes López-Morales, Nikolay Nikolov, David K. Sing, Gregory W. Henry, Claire Baxter, Jean-Michel Désert, Joanna K. Barstow, Thomas Mikal-Evans, Vincent Bourrier, Panayotis Lavvas, Hannah R. Wakeford, Michael H. Williamson, Jorge Sanz-Forcada, Lars A. Buchhave, Ofer Cohen, Antonio García Muñoz Jul 2020

The Hubble Space Telescope Pancet Program: An Optical To Infrared Transmission Spectrum Of Hat-P-32ab, Munazza K. Alam, Mercedes López-Morales, Nikolay Nikolov, David K. Sing, Gregory W. Henry, Claire Baxter, Jean-Michel Désert, Joanna K. Barstow, Thomas Mikal-Evans, Vincent Bourrier, Panayotis Lavvas, Hannah R. Wakeford, Michael H. Williamson, Jorge Sanz-Forcada, Lars A. Buchhave, Ofer Cohen, Antonio García Muñoz

Information Systems and Engineering Management Research Publications

We present a 0.3−5 μm transmission spectrum of the hot Jupiter HAT-P-32Ab observed with the Space Telescope Imaging Spectrograph and Wide Field Camera 3 instruments mounted on the Hubble Space Telescope, combined with Spitzer Infrared Array Camera photometry. The spectrum is composed of 51 spectrophotometric bins with widths ranging between 150 and 400 Å, measured to a median precision of 215 ppm. Comparisons of the observed transmission spectrum to a grid of 1D radiative-convective equilibrium models indicate the presence of clouds/hazes, consistent with previous transit observations and secondary eclipse measurements. To provide more robust constraints on the planet's atmospheric properties, …

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Constitutive Model Of Lateral Unloading Creep Of Soft Soil Under Excess Pore Water Pressure, Wei Huang, Kejun Wen, Xiaojia Deng, Junjie Li, Zhijian Jiang, Yang Li, Lin Li, Farshad Amini Jun 2020

Constitutive Model Of Lateral Unloading Creep Of Soft Soil Under Excess Pore Water Pressure, Wei Huang, Kejun Wen, Xiaojia Deng, Junjie Li, Zhijian Jiang, Yang Li, Lin Li, Farshad Amini

Civil and Architectural Engineering Faculty Research

Presented in this paper is a study on the lateral unloading creep tests under different excess pore water pressures. The marine sedimentary soft soil in Shenzhen, China, was selected in this study. The results show that the excess pore water pressure plays a significant role in enhancing the unloading creep of soft soil. Higher excess pore water pressure brings more obvious creep deformation of soft soil and lower ultimate failure load. Meanwhile, the viscoelastic and the viscoplastic modulus of soft soil were found to exponentially decline with creep time. A modified merchant model and a combined model of the modified …

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Kr Persei, A Mid-F Eclipsing Binary With A One-Day Period, James R. Sowell, Emily Hollingworth, Francis C. Fekel, Matthew W. Muterspaugh, Horace Dale, Alexander D. Savello, Jeffrey L. Coughlin, Richard M. Williamon Jun 2020

Kr Persei, A Mid-F Eclipsing Binary With A One-Day Period, James R. Sowell, Emily Hollingworth, Francis C. Fekel, Matthew W. Muterspaugh, Horace Dale, Alexander D. Savello, Jeffrey L. Coughlin, Richard M. Williamon

Information Systems and Engineering Management Research Publications

KR Per is a partially eclipsing binary with an orbital period of 0.9960798 days, very close to one sidereal day, making it difficult to obtain extensive phase coverage in a reasonable amount of time. We used the Wilson–Devinney program to determine its orbital elements and stellar absolute dimensions from recently acquired radial velocities and differential BVRI observations that were supplemented with previous differential UBV measurements and published times of minima. The two components are each F5 V stars with masses of and . The radii are and . The orbital period of the eclipsing system is variable and more times …

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Absolute Dimensions Of The Unevolved F-Type Eclipsing Binary Bt Vulpeculae, Guillermo Torres, Claud H. Sandberg Lacy, Francis C. Fekel, Matthew W. Muterspaugh May 2020

Absolute Dimensions Of The Unevolved F-Type Eclipsing Binary Bt Vulpeculae, Guillermo Torres, Claud H. Sandberg Lacy, Francis C. Fekel, Matthew W. Muterspaugh

Information Systems and Engineering Management Research Publications

We report extensive differential V-band photometry and high-resolution spectroscopy for the 1.14 day, detached, double-lined eclipsing binary BT Vul (F0+F7). Our radial-velocity monitoring and light-curve analysis lead to absolute masses and radii of ${M}_{1}=1.5439\pm 0.0098\,{{ \mathcal M }}_{\odot }^{{\rm{N}}}$ and ${R}_{1}=1.536\pm 0.018\,{{ \mathcal R }}_{\odot }^{{\rm{N}}}$ for the primary, and ${M}_{2}=1.2196\pm 0.0080\,{{ \mathcal M }}_{\odot }^{{\rm{N}}}$ and ${R}_{2}=1.151\pm 0.029\,{{ \mathcal R }}_{\odot }^{{\rm{N}}}$ for the secondary. The effective temperatures are 7270 ± 150 K and 6260 ± 180 K, respectively. Both stars are rapid rotators, and the orbit is circular. A comparison with stellar evolution models from the MESA Isochrones …

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Updated Parameters And A New Transmission Spectrum Of Hd 97658b, Xueying Guo, Ian J. M. Crossfield, Diana Dragomir, Molly Kosiarek, Joshua Lothringer, Thomas Mikal-Evans, Lee J. Rosenthal, Björn Benneke, Heather Knutson, Paul A. Dalba, Eliza M. R. Kempton, Gregory W. Henry, Peter R. Mccullough, Travis Barman, Sarah C. Blunt, Ashley Chontos, Jonathan J. Fortney, Benjamin Fulton, Lea A. Hirsch, Andrew W. Howard, Howard Isaacson, Jaymie Matthews, Teo Mocnik, Caroline Morley, Erik A. Petigura, Lauren M. Weiss Apr 2020

Updated Parameters And A New Transmission Spectrum Of Hd 97658b, Xueying Guo, Ian J. M. Crossfield, Diana Dragomir, Molly Kosiarek, Joshua Lothringer, Thomas Mikal-Evans, Lee J. Rosenthal, Björn Benneke, Heather Knutson, Paul A. Dalba, Eliza M. R. Kempton, Gregory W. Henry, Peter R. Mccullough, Travis Barman, Sarah C. Blunt, Ashley Chontos, Jonathan J. Fortney, Benjamin Fulton, Lea A. Hirsch, Andrew W. Howard, Howard Isaacson, Jaymie Matthews, Teo Mocnik, Caroline Morley, Erik A. Petigura, Lauren M. Weiss

Information Systems and Engineering Management Research Publications

Recent years have seen increasing interest in the characterization of sub-Neptune-sized planets because of their prevalence in the Galaxy, contrasted with their absence in our solar system. HD 97658 is one of the brightest stars hosting a planet of this kind, and we present the transmission spectrum of this planet by combining four Hubble Space Telescope transits, 12 Spitzer/IRAC transits, and eight MOST transits of this system. Our transmission spectrum has a higher signal-to-noise ratio than those from previous works, and the result suggests that the slight increase in transit depth from wavelength 1.1–1.7 μm reported in previous works on …

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Fundamental Results On S-Closures, William D. Taylor Apr 2020

Fundamental Results On S-Closures, William D. Taylor

Mathematical Sciences Faculty Research

This paper establishes the fundamental properties of the s-closures, a recently introduced family of closure operations on ideals of rings of positive characteristic. The behavior of the s-closure of homogeneous ideals in graded rings is studied, and criteria are given for when the s-closure of an ideal can be described exactly in terms of its tight closure and rational powers. Sufficient conditions are established for the weak s-closure to equal to the s-closure. A generalization of the Briancon-Skoda theorem is given which compares any two different s-closures applied to powers of the same ideal.

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Optical To Near-Infrared Transmission Spectrum Of The Warm Sub-Saturn Hat-P-12b, Ian Wong, Björn Benneke, Peter Gao, Heather Knutson, Yayaati Chachan, Gregory W. Henry, Drake Deming, Tiffany Kataria, Elspeth K. H. Lee, Nikolay Nikolov, David K. Sing, Gilda E. Ballester, Nathaniel J. Baskin, Hannah R. Wakeford, Michael H. Williamson Apr 2020

Optical To Near-Infrared Transmission Spectrum Of The Warm Sub-Saturn Hat-P-12b, Ian Wong, Björn Benneke, Peter Gao, Heather Knutson, Yayaati Chachan, Gregory W. Henry, Drake Deming, Tiffany Kataria, Elspeth K. H. Lee, Nikolay Nikolov, David K. Sing, Gilda E. Ballester, Nathaniel J. Baskin, Hannah R. Wakeford, Michael H. Williamson

Information Systems and Engineering Management Research Publications

We present the transmission spectrum of HAT-P-12b through a joint analysis of data obtained from the Hubble Space Telescope Space Telescope Imaging Spectrograph and Wide Field Camera 3 and Spitzer, covering the wavelength range 0.3–5.0 μm. We detect a muted water vapor absorption feature at 1.4 μm attenuated by clouds, as well as a Rayleigh scattering slope in the optical indicative of small particles. We interpret the transmission spectrum using both the state-of-the-art atmospheric retrieval code SCARLET and the aerosol microphysics model CARMA. These models indicate that the atmosphere of HAT-P-12b is consistent with a broad range of metallicities between …

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Observations Of Binary Stars With The Differential Speckle Survey Instrument. Ix. Observations Of Known And Suspected Binaries, And A Partial Survey Of Be Stars, Elliott P. Horch, Gerard T. Van Belle, James W. Davidson Jr., Daryl W. Willmarth, Francis C. Fekel, Matthew W. Muterspaugh, Dana I. Casetti-Dinescu, Frederick W. Hahne, Nicole M. Granucci, Catherine A. Clark, Jennifer G. Winters, Justin D. Rupert, Samuel A. Weiss, Nicole M. Colton, Daniel A. Nusdeo, Todd J. Henry Apr 2020

Observations Of Binary Stars With The Differential Speckle Survey Instrument. Ix. Observations Of Known And Suspected Binaries, And A Partial Survey Of Be Stars, Elliott P. Horch, Gerard T. Van Belle, James W. Davidson Jr., Daryl W. Willmarth, Francis C. Fekel, Matthew W. Muterspaugh, Dana I. Casetti-Dinescu, Frederick W. Hahne, Nicole M. Granucci, Catherine A. Clark, Jennifer G. Winters, Justin D. Rupert, Samuel A. Weiss, Nicole M. Colton, Daniel A. Nusdeo, Todd J. Henry

Information Systems and Engineering Management Research Publications

We report 370 measures of 170 components of binary and multiple-star systems, obtained from speckle imaging observations made with the Differential Speckle Survey Instrument at Lowell Observatory's Discovery Channel Telescope in 2015 through 2017. Of the systems studied, 147 are binary stars, 10 are seen as triple systems, and 1 quadruple system is measured. Seventy-six high-quality nondetections and 15 newly resolved components are presented in our observations. The uncertainty in relative astrometry appears to be similar to our previous work at Lowell, namely, linear measurement uncertainties of approximately 2 mas, and the relative photometry appears to be uncertain at the …

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Detection Of Na, K, And H2o In The Hazy Atmosphere Of Wasp-6b, Aarynn L. Carter, Nikolay Nikolov, David K. Sing, Munazza K. Alam, Jayesh M. Goyal, Thomas Mikal-Evans, Hannah R. Wakeford, Gregory W. Henry, Sam Morrell, Mercedes López-Morales, Barry Smalley, Panayotis Lavvas, Joanna K. Barstow, Antonio García Muñoz, Neale P. Gibson, Paul A. Wilson Apr 2020

Detection Of Na, K, And H2o In The Hazy Atmosphere Of Wasp-6b, Aarynn L. Carter, Nikolay Nikolov, David K. Sing, Munazza K. Alam, Jayesh M. Goyal, Thomas Mikal-Evans, Hannah R. Wakeford, Gregory W. Henry, Sam Morrell, Mercedes López-Morales, Barry Smalley, Panayotis Lavvas, Joanna K. Barstow, Antonio García Muñoz, Neale P. Gibson, Paul A. Wilson

Information Systems and Engineering Management Research Publications

We present new observations of the transmission spectrum of the hot Jupiter WASP-6b both from the ground with the Very Large Telescope FOcal Reducer and Spectrograph (FORS2) from 0.45 to 0.83 μm, and space with the Transiting Exoplanet Survey Satellite from 0.6 to 1.0 μm and the Hubble Space Telescope (HST) Wide Field Camera 3 from 1.12 to 1.65 μm. Archival data from the HST Space Telescope Imaging Spectrograph (STIS) and Spitzer are also re-analysed on a common Gaussian process framework, of which the STIS data show a good overall agreement with the overlapping FORS2 data. We also explore the …

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