Physical Sciences and Mathematics Commons^™

Inexact Tensor Methods And Their Application To Stochastic Convex Optimization, Artem Agafonov, Dmitry Kamzolov, Pavel Dvurechensky, Alexander Gasnikov, Martin Takac

Machine Learning Faculty Publications

We propose general non-accelerated and accelerated tensor methods under inexact information on the derivatives of the objective, analyze their convergence rate. Further, we provide conditions for the inexactness in each derivative that is sufficient for each algorithm to achieve a desired accuracy. As a corollary, we propose stochastic tensor methods for convex optimization and obtain sufficient mini-batch sizes for each derivative. © 2020, CC BY.

The Nebraska Water Leaders Academy Graduates’ Influence On Community Capitals And Community Capacity, Dakota W. Staggs, Mark E. Burbach, Gina S. Matkin, Cheryl Burkhart-Kriesel

School of Natural Resources: Faculty Publications

An overarching goal of the Nebraska Water Leaders Academy is to prepare a diverse group of Nebraskans from across the state to impact change in their communities by working together to solve wicked water problems. With 136 graduates from across Nebraska there is potential for graduates to effect change and impact their communities’ capitals (i.e., Built, Financial, Political, Social, Human, Cultural, and Natural). This study explored the impact of Academy graduates on their communities’ capitals and community capacity to prepare for future challenges from the perspective of graduates and community members. Findings show that Academy graduates are impacting their communities …

Applied Topology Ams 528, Harrison Dekker

Library Impact Statements

No abstract provided.

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 …

Dach1 Mutation Frequency In Endometrial Cancer Is Associated With High Tumor Mutation Burden, Mckayla J. Riggs, Nan Lin, Chi Wang, Dava W. Piecoro, Rachel W. Miller, Oliver A. Hampton, Mahadev Rao, Frederick R. Ueland, Jill M. Kolesar

Obstetrics and Gynecology Faculty Publications

OBJECTIVE: DACH1 is a transcriptional repressor and tumor suppressor gene frequently mutated in melanoma, bladder, and prostate cancer. Loss of DACH1 expression is associated with poor prognostic features and reduced overall survival in uterine cancer. In this study, we utilized the Oncology Research Information Exchange Network (ORIEN) Avatar database to determine the frequency of DACH1 mutations in patients with endometrial cancer in our Kentucky population.

METHODS: We obtained clinical and genomic data for 65 patients with endometrial cancer from the Markey Cancer Center (MCC). We examined the clinical attributes of the cancers by DACH1 status by comparing whole-exome sequencing (WES), …

Quantum Simulation Of The Schrodinger Equation Using Ibm's Quantum Computers, Mohamed Abouelela

Capstone and Graduation Projects

This thesis explores the capabilities of a quantum computer to simulate quantum systems. We give an introduction to the basics of quantum computing with the Bernstein-Vazirani algorithm as a demonstration. Four quantum systems are then simulated using IBM's QASM simulator using 6 qubits: the free particle, eigenstate of an infinite-well, particle in a step potential, and quantum tunneling. Because of the high number of gates, a 6-qubit simulation will not be feasible on current quantum computers. The number of qubits was, thus, reduced to 4 qubits, and was simulated on IBM's 5 qubit quantum computers (ibmq 5 vigo). We conclude …

Sensitivity Analysis Of An Agent-Based Simulation Model Using Reconstructability Analysis, Andey M. Nunes, Martin Zwick, Wayne Wakeland

Systems Science Faculty Publications and Presentations

Reconstructability analysis, a methodology based on information theory and graph theory, was used to perform a sensitivity analysis of an agent-based model. The NetLogo BehaviorSpace tool was employed to do a full 2^k factorial parameter sweep on Uri Wilensky’s Wealth Distribution NetLogo model, to which a Gini-coefficient convergence condition was added. The analysis identified the most influential predictors (parameters and their interactions) of the Gini coefficient wealth inequality outcome. Implications of this type of analysis for building and testing agent-based simulation models are discussed.

A Multidisciplinary Approach To Investigate Deep-Pelagic Ecosystem Dynamics In The Gulf Of Mexico Following Deepwater Horizon, April Cook, Andrea Bernard, Kevin M. Boswell, Heather Bracken-Grissom Dr., Marta D'Elia, Sergio Derada, Cole Easson, David English, Ron Eytan, Tamara Frank, Chuanmin Hu, Matt Johnston, Heather Judkins, Chad Lembke, Jose Lopez, Rosanna Milligan, Jon A. Moore, Brad Penta, Nina Pruzinsky, John A. Quinlan, Travis M. Richards, Isabel C. Romero, Mahmood S. Shivji, Michael Vecchione, Max D. Weber, R.J. David Wells, Tracey Sutton

Marine & Environmental Sciences Faculty Articles

The pelagic Gulf of Mexico (GoM) is a complex system of dynamic physical oceanography (western boundary current, mesoscale eddies), high biological diversity, and community integration via diel vertical migration and lateral advection. Humans also heavily utilize this system, including its deep-sea components, for resource extraction, shipping, tourism, and other commercial activity. This utilization has had impacts, some with disastrous consequences. The Deepwater Horizon oil spill (DWHOS) occurred at a depth of ∼1500 m (Macondo wellhead), creating a persistent and toxic mixture of hydrocarbons and dispersant in the deep-pelagic (water column below 200 m depth) habitat. In order to assess the …

Medical Marijuana And Opioids (Memo) Study: Protocol Of A Longitudinal Cohort Study To Examine If Medical Cannabis Reduces Opioid Use Among Adults With Chronic Pain, Chinazo O. Cunningham, Joanna L. Starrels, Chenshu Zhang, Marcus A. Bachhuber, Nancy L. Sohler, Frances R. Levin, Haruka Minami, Deepika E. Slawek, Julia H. Arnsten

School of Medicine Faculty Publications

Introduction In the USA, opioid analgesic use and overdoses have increased dramatically. One rapidly expanding strategy to manage chronic pain in the context of this epidemic is medical cannabis. Cannabis has analgesic effects, but it also has potential adverse effects. Further, its impact on opioid analgesic use is not well studied. Managing pain in people living with HIV is particularly challenging, given the high prevalence of opioid analgesic and cannabis use. This study's overarching goal is to understand how medical cannabis use affects opioid analgesic use, with attention to Δ9-tetrahydrocannabinol and cannabidiol content, HIV outcomes and adverse events. Methods and …

Marine Geobiology Ocg 502, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Global Ocean Change Ocg 511, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Marine Geobiology Ocg 5xx, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Near Conformal Perturbation Theory In Syk Type Models, Sumit R. Das, Animik Ghosh, Antal Jevicki, Kenta Suzuki

Physics and Astronomy Faculty Publications

We present a systematic procedure to extract the dynamics of the low energy soft mode in SYK type models with a single energy scale J and emergent reparametrization symmetry in the IR. This is given in the framework of the perturbative scheme of arXiv:1608.07567 based on a specific (off-shell) breaking of conformal invariance in the UV, adjusted to yield the exact large-N saddle point. While this breaking term formally vanishes on-shell, it has a non-trivial effect on correlation functions and the effective action. In particular, it leads to the Schwarzian action with a specific coupling to bi-local matter. The …

Pyxtal_Ff: A Python Library For Automated Force Field Generation, Howard Yanxon, David Zagaceta, Binh Tang, David S. Matteson, Qiang Zhu

Physics & Astronomy Faculty Research

We present PyXtal_FF—a package based on Python programming language—for developing machine learning potentials (MLPs). The aim of PyXtal_FF is to promote the application of atomistic simulations through providing several choices of atom-centered descriptors and machine learning regressions in one platform. Based on the given choice of descriptors (including the atom-centered symmetry functions, embedded atom density, SO4 bispectrum, and smooth SO3 power spectrum), PyXtal_FF can train MLPs with either generalized linear regression or neural network models, by simultaneously minimizing the errors of energy/forces/stress tensors in comparison with the data from ab-initio simulations. The trained MLP model from PyXtal_FF is interfaced with …

Local Electronic And Magnetic Properties Of The Doped Topological Insulators Bi₂Se₃:Ca And Bi₂Te₃:Mn Investigated Using Ion-Implanted ⁸Li Β-Nmr, Ryan M. L. Mcfadden, Aris Chatzichristos, David L. Cortie, Derek Fujimoto, Yew San Hor, Huiwen Ji, Victoria L. Karner, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report β-NMR measurements in Bi₂Se₃:Ca and Bi₂Te₃:Mn single crystals using ⁸Li⁺ implanted to depths on the order of 100 nm. Above ∼200K, spin-lattice relaxation reveals diffusion of ⁸Li⁺, with activation energies of ∼0.4eV (∼0.2eV) in Bi₂Se₃:Ca (Bi₂Te₃:Mn). At lower temperatures, the NMR properties are those of a heavily doped semiconductor in the metallic limit, with Korringa relaxation and a small, negative, temperature-dependent Knight shift in Bi₂Se₃:Ca. From this, we make a detailed comparison with …

Schrödinger-Poisson Systems With Singular Potential And Critical Exponent, Senli Liu, Haibo Chen, Zhaosheng Feng

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this article we study the Schrödinger-Poisson system−∆ u+ V (| x|) u+ λφu= f (u), x∈ R3,−∆ φ= u2, x∈ R3, where V is a singular potential with the parameter α and the nonlinearity f satisfies critical growth. By applying a generalized version of Lions-type theorem and the Nehari manifold theory, we establish the existence of the nonnegative ground state solution when λ= 0. By the perturbation method, we obtain a nontrivial solution to above system when λ= 0.

Salt Marsh Elevation Limit Determined After Subsidence From Hydrologic Change And Hydrocarbon Extraction, R. Eugene Turner, Yu Mo

Faculty Publications

Levee construction aboveground and hydrocarbon removal from belowground in coastal wetlands can create hydrologic changes that increase plant stress through flooding. But the significance of the subsidence they cause individually or in combination is contested. This study untangled them to demonstrate elevational limits of salt marshes by studying dredged and natural waterways in two salt marshes in Louisiana, USA. The areas had a homogenous plant cover before drilling for oil and gas extraction peaked in the 1960s, and now are a mixed network of natural waterways and dredged canals used to drill wells with an average drill date of 1965.8 …

Evolution Of Magnetic-Field-Induced Ordering In The Layered Structure Quantum Heisenberg Triangular-Lattice Antiferromagnet Ba3Cosb2O9, Nathanael Alexander Fortune, Q. Huang, T. Hong, J. Ma, E. S. Choi, S. T. Hannahs, Z. Y. Zhao, X. F. Sun, Y. Takano, H. D. Zhou

Physics: Faculty Publications

Quantum fluctuations in the effective spin-1/2 layered structure triangular-lattice quantum Heisenberg antiferromagnet Ba₃CoSb₂O₉ lift the classical degeneracy of the antiferromagnetic ground state in magnetic field, producing a series of novel spin structures for magnetic fields applied within the crystallographic ab plane, including a celebrated collinear ‘up-up-down’ spin ordering with magnetization equal to 1/3 of the saturation magnetization over an extended field range. Theoretically unresolved, however, are the effects of interlayer antferromagnetic coupling and transverse magnetic fields on the ground states of this system. Additional magnetic-field-induced phase transitions are theoretically expected and in some cases have …

Acid-Triggered Self-Assembled Egg White Protein-Coated Gold Nanoclusters For Selective Fluorescent Detection Of Fe3+, No2-, And Cysteine, Wenyan Li, Xiangping Wen, Hemiao Zhao, Wenjun Yan, John F. Trant, Yingqi Li

Chemistry and Biochemistry Publications

Herein, we present a simple and economical synthesis for the first multianalyte probe able to selectively quantify the concentrations of Fe3+, NO2-, and cysteine. It comprises H+-triggered self-assembled gold nanoclusters (AuNCs@EW/H+, AuEHs), showing enhanced red fluorescence at 640 nm. The AuEH is a good fluorescent nanosensor for Fe3+ and NO2- with detection limits of 1.40 and 2.82 nM, respectively. Iron detection, through fluorescence quenching, occurs because of nanocluster aggregation elicited by the complexation of Fe3+ with amino acids on the surface of AuEH; nitrite detection likely proceeds through fluorescence quenching via the disassembly of the nanoclusters following irreversible oxidation by …

Data: The Good, The Bad And The Ethical, John D. Kelleher, Filipe Cabral Pinto, Luis M. Cortesao

Articles

It is often the case with new technologies that it is very hard to predict their long-term impacts and as a result, although new technology may be beneficial in the short term, it can still cause problems in the longer term. This is what happened with oil by-products in different areas: the use of plastic as a disposable material did not take into account the hundreds of years necessary for its decomposition and its related long-term environmental damage. Data is said to be the new oil. The message to be conveyed is associated with its intrinsic value. But as in …

The Family Of Bicircular Matroids Closed Under Duality, Vaidy Sivaraman, Daniel Slilaty

Mathematics and Statistics Faculty Publications

We characterize the 3-connected members of the intersection of the class of bicircular and cobi- circular matroids. Aside from some exceptional matroids with rank and corank at most 5, this class consists of just the free swirls and their minors.

Modulation Of Late Pleistocene Enso Strength By The Tropical Pacific Thermocline, Gerald T. Rustic, Pratigya J. Polissar, Ana Christina Ravelo, Sarah M. White

School of Earth & Environment Faculty Scholarship

The El Niño Southern Oscillation (ENSO) is highly dependent on coupled atmosphere-ocean interactions and feedbacks, suggesting a tight relationship between ENSO strength and background climate conditions. However, the extent to which background climate state determines ENSO behavior remains in question. Here we present reconstructions of total variability and El Niño amplitude from individual foraminifera distributions at discrete time intervals over the past ~285,000 years across varying atmospheric CO2 levels, global ice volume and sea level, and orbital insolation forcing. Our results show a strong correlation between eastern tropical Pacific Ocean mixed-layer thickness and both El Niño amplitude and central Pacific …

African Land Mammal Ages, John Van Couvering, Eric Delson

Publications and Research

We define 17 African land mammal ages, or AFLMAs, covering the Cenozoic record of the Afro-arabian continent, the planet’s second largest land mass. While fossiliferous deposits are absent on the eroded plateau of the continent’s interior, almost 800 fossil genera from over 350 locations have now been identified in coastal deposits, karst caves, and in the Neogene rift valleys. Given a well-developed geochronologic framework, together with continuing revision to the fossil record—both stimulated by the story of human evolution in Africa—and also to compensate for the variation in fossil ecosystems across such great distances, the AFLMAs are biochronological units defined …

Approximation By The K^Lambda Means Of Fourier Series And Conjugate Series Of Functions In H_{Alpha,P}, Ben Landon, Holly Carley, R. N. Mohapatra

Publications and Research

No abstract provided.

Analysis And Implementation Of The Maximum Likelihood Expectation Maximization Algorithm For Find, Angus Boyd Jameson

Student Research Projects

This thesis presents an organized explanation and breakdown of the Maximum Likelihood Expectation Maximization image reconstruction algorithm. This background research was used to develop a means of implementing the algorithm into the imaging code for UNH's Field Deployable Imaging Neutron Detector to improve its ability to resolve complex neutron sources. This thesis provides an overview for this implementation scheme, and include the results of a couple of reconstruction tests for the algorithm. A discussion is given on the current state of the algorithm and its integration with the neutron detector system, and suggestions are given for how the work and …

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 …

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 …

A Spectral Adjustment For Spatial Confounding, Yawen Guan, Garritt L. Page, Brian J. Reich, Massimo Ventrucci, Shu Yang

Department of Statistics: Faculty Publications

Adjusting for an unmeasured confounder is generally an intractable problem, but in the spatial setting it may be possible under certain conditions. In this paper, we derive necessary conditions on the coherence between the treatment variable of interest and the unmeasured confounder that ensure the causal effect of the treatment is estimable. We specify our model and assumptions in the spectral domain to allow for different degrees of confounding at different spatial resolutions. The key assumption that ensures identifiability is that confounding present at global scales dissipates at local scales. We show that this assumption in the spectral domain is …

Gravity Waves, Na Lidar, Yafang Guo, Alan Z. Liu

Publications

Vertical energy transports due to dissipating gravity waves in the mesopause region (85–100 km) are analyzed using over 400 h of observational data obtained from a narrow-band sodium wind-temperature lidar located at Andes Lidar Observatory (ALO), Cerro Pachón (30.25°S, 70.73°W), Chile. Sensible heat flux is directly estimated using measured temperature and vertical wind; energy flux is estimated from the vertical wavenumber and frequency spectra of temperature perturbations; and enthalpy flux is derived based on its relationship with sensible heat and energy fluxes. Sensible heat flux is mostly downward throughout the region. Enthalpy flux exhibits an annual oscillation with maximum downward …

Multipoint Observations Of Compressional Pc5 Pulsations In The Dayside Magnetosphere And Corresponding Particle Signatures, Galina Korotova, David Sibeck, Mark Engebretson, Michael Balikhin, Scott Thaller, Craig Kletzing, Harlan Spence, Robert Redmon

Faculty Authored Articles

We use Van Allen Probes (Radiation Belt Storm Probes A and B, henceforth RBSP-A and RBSP-B) and GOES-13 and GOES-15 (henceforth G-13 and G-15) multipoint magnetic field, electric field, plasma, and energetic particle observations to study the spatial, temporal, and spectral characteristics of compressional Pc5 pulsations observed during the recovery phase of a strong geomagnetic storm on 1 January 2016. From ∼ 19:00 to 23:02 UT, successive magnetospheric compressions enhanced the peak-to-peak amplitudes of Pc5 waves with 4.5'6.0 mHz frequencies from 0' 2 to 10'15 nT at both RBSP-A and RBSP-B, particularly in the prenoon magnetosphere. Poloidal Pc4 pulsations with …