Physical Sciences and Mathematics Commons^™

Validation Of Ace-Fts Version 3.5 Noy Species Profiles Using Correlative Satellite Measurements, Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, Chris A. Mclinden, Peter F. Bernath, Adam E. Bourassa, John P. Burrows, Doug A. Degenstein, Bernd Funke, Didier Fussen

Chemistry & Biochemistry Faculty Publications

The ACE-FTS (Atmospheric Chemistry Experiment - Fourier Transform Spectrometer) instrument on the Canadian SCISAT satellite, which has been in operation for over 12 years, has the capability of deriving stratospheric profiles of many of the NOy (N + NO + NO₂ + NO₃ + 2 x N₂O₅ + HNO₃ + HNO₄ + ClONO₂ + BrONO₂) species. Version 2.2 of ACE-FTS NO, NO₂, HNO₃, N₂O₅, and ClONO₂ has previously been validated, and this study compares the most recent version (v3.5) of …

Vanadium Toxicological Potential Versus Its Pharmacological Activity: New Developments And Research, Agnieszka Ścibior, Juan Llopis, Alvin A. Holder, Mario Altamirano-Lozano

Chemistry & Biochemistry Faculty Publications

Scibior, A., Llopis, J., Holder, A. A., & Altamirano-Lozano, M. (2016). Vanadium toxicological potential versus its pharmacological activity: New developments and research. Oxidative Medicine and Cellular Longevity, 2016, 1-2. doi: 10.1155/2016/7612347

Satellite Observations Of Stratospheric Hydrogen Flouride And Comparisons With Slimcat Calculations, Jeremy J. Harrison, Martyn P. Chipperfield, Christopher D. Boone, Sandip S. Dhomse, Peter F. Bernath, Lucien Froidevaux

Chemistry & Biochemistry Faculty Publications

The vast majority of emissions of fluorine-containing molecules are anthropogenic in nature, e.g. chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs). Many of these fluorine-containing species deplete stratospheric ozone and are regulated by the Montreal Protocol. Once in the atmosphere they slowly degrade, ultimately leading to the formation of hydrogen fluoride (HF), the dominant reservoir of stratospheric fluorine due to its extreme stability. Monitoring the growth of stratospheric HF is therefore an important marker for the success of the Montreal Protocol. We report the comparison of global distributions and trends of HF measured in the Earth's atmosphere by the satellite remote-sensing …

Single Nanoparticle Plasmonic Spectroscopy For Study Of The Efflux Function Of Multidrug Abc Membrance Transporters Of Single Live Cells, Lauren M. Browning, Kerry J. Lee, Pavan K. Cherukuri, Prakash D. Nallathamby, Seth Warren, Jean-Michel Jault, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

ATP-binding cassette (ABC) membrane transporters exist in all living organisms and play key roles in a wide range of cellular and physiological functions. The ABC transporters can selectively extrude a wide variety of structurally and functionally unrelated substrates, leading to multidrug resistance. Despite extensive study, their efflux molecular mechanisms remain elusive. In this study, we synthesized and characterized purified silver nanoparticles (Ag NPs) (97 ± 13 nm in diameter), and used them as photostable optical imaging probes to study efflux kinetics of ABC membrane transporters (BmrA) of single live cells (B. subtilis). The NPs with concentrations up to …

The Role Of Microbial Exopolymers In Determining The Fate Of Oil And Chemical Dispersants In The Ocean, Antonietta Quigg, Uta Passow, Wei-Chun Chin, Chen Xu, Shawn Doyle, Laura Bretherton, Manoj Kamalanathan, Alicia K. Williams, Jason B. Sylvan, Zoe V. Finkel, Anthony H. Knap, Kathleen A. Schwehr, Saijin Zhang, Luni Sun, Terry L. Wade, Wassim Obeid, Patrick G. Hatcher, Peter H. Santschi

Chemistry & Biochemistry Faculty Publications

The production of extracellular polymeric substances (EPS) by planktonic microbes can influence the fate of oil and chemical dispersants in the ocean through emulsification, degradation, dispersion, aggregation, and/or sedimentation. In turn, microbial community structure and function, including the production and character of EPS, is influenced by the concentration and chemical composition of oil and chemical dispersants. For example, the production of marine oil snow and its sedimentation and flocculent accumulation to the seafloor were observed on an expansive scale after the Deepwater Horizon oil spill in the Northern Gulf of Mexico in 2010, but little is known about the underlying …

Plutonium Immobilization And Mobilization By Soil Organic Matter, Peter H. Santschi, Kathleen A. Schwehr, Chen Xu, Matthew Athon, Yi-Fang Ho, Patrick G. Hatcher, Nicole Didonato, Daniel I. Kaplan

Chemistry & Biochemistry Faculty Publications

The human and environmental risks associated with Pu disposal, remediation, and nuclear accidents scenarios stems mainly from the very long half-lives of several of its isotopes. The SRS, holding one-third of the nation’s Pu inventory, has a long-term stewardship commitment to investigation of Pu behavior in the groundwater and downgradient vast wetlands. Pu is believed to be essentially immobile due to its low solubility and high particle reactivity to mineral phase or natural organic matter (NOM). For example, in sediments collected from a region of SRS, close to a wetland and a groundwater plume, 239,240Pu concentrations suggest immobilization by NOM …

Anticancer, Biophysical And Computational Investigations Of Half-Sandwich Ruthenium(Ii) Thiosemicarbazone Complexes: The Effect Of Arene Versus Thiacrown Face-Cap, Floyd A. Beckford, Alyssa Stott, P. Canisius Mbarushimana, Marc-Andre Leblanc, Kinsey Hall, Samantha Smith, Jimmie L. Bullock, Dennis J. Houghton, Alvin A. Holder, Nikolay Gerasimchuk, Antonio Gonzalez-Sarrías

Chemistry & Biochemistry Faculty Publications

A series of half-sandwich ruthenium complexes, two containing an arene face-cap and the other a thiacrown ether face-cap were synthesized to investigate the necessity of the arene for anticancer activity in this class of compounds. The complexes are formulated as [(h⁶-p-cymene)Ru(dmabTSC)Cl]PF₆, [(h⁶-benzene)Ru(dmabTSC)Cl]PF₆ (arene complexes), and [([9]aneS₃(dmabTSC)Cl]PF₆ (dmabTSC = dimethylaminobenzaldehye thiosemicarbazone). It was observed that none of the complexes showed good anticancer activity in vitro against HCT-116 and Caco-2 (colon adenocarcinoma) cells. All three complexes can bind strongly to calf-thymus DNA with binding constants on the order of 10 …

Measurement Of Antioxidant Activity Toward Superoxide In Natural Waters, D. Whitney King, Emma Berger, Zachary Helm, Eleanor Irish, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Antioxidants are a class of molecules that provide a protective function against reactive oxygen species (ROS) in biological systems by out competing physiologically important molecules for ROS oxidation. In natural waters, the reactivity of antioxidants gives an estimate of oxidative stress, and may determine the reactivity and distribution of reactive oxidants. We present an analytical method to measure antioxidant activity in natural waters through the competition between ascorbic acid, an antioxidant, and MCLA, a chemiluminescent probe for superoxide. A numerical kinetic model of the analytical method has been developed to optimize analytical performance. Measurements of antioxidant concentrations in pure and …

Characterization Of Biochars Produced From Peanut Hulls And Pine Wood With Different Pyrolysis Conditions, James W. Lee, Bob Hawkins, Michelle K. Kidder, Barbara R. Evans, A. C. Buchanan, Danny Day

Chemistry & Biochemistry Faculty Publications

Background

Application of modern biomass pyrolysis methods for production of biofuels and biochar is potentially a significant approach to enable global carbon capture and sequestration. To realize this potential, it is essential to develop methods that produce biochar with the characteristics needed for effective soil amendment.

Methods

Biochar materials were produced from peanut hulls and pine wood with different pyrolysis conditions, then characterized by cation exchange (CEC) capacity assays, nitrogen adsorption–desorption isotherm measurements, micro/nanostructural imaging, infrared spectra and elemental analyses.

Results

Under a standard assay condition of pH 8.5, the CEC values of the peanut hull-derived biochar materials, ranging from …

Water Vapour Variability In The High-Latitude Upper Troposphere- Part 2: Impact Of Volcanic Eruptions, Christopher E. Sioris, Jason Zou, C. Thomas Mcelroy, Chris D. Boone, Patrick E. Sheese, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

The impact of volcanic eruptions on water vapour in the high-latitude upper troposphere is studied using deseasonalized time series based on observations by the Atmospheric Chemistry Experiment (ACE) water vapour sensors, namely MAESTRO (Measurements of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) and the Fourier Transform Spectrometer (ACE-FTS). The two eruptions with the greatest impact on the high-latitude upper troposphere during the time frame of this satellitebased remote sensing mission are chosen. The Puyehue-Cordón Caulle volcanic eruption in June 2011 was the most explosive in the past 24 years and is shown to be able to account …

Global Stratospheric Measurements Of The Isotopologues Of Methane From The Atmospheric Chemistry Experiment Fourier Transform Spectrometer, Eric M. Buzan, Chris A. Beale, Chris. D. Boone, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

This paper presents an analysis of observations of methane and its two major isotopologues, CH₃D and ¹³CH₄, from the Atmospheric Chemistry Experiment (ACE) satellite between 2004 and 2013. Additionally, atmospheric methane chemistry is modeled using the Whole Atmospheric Community Climate Model (WACCM). ACE retrievals of methane extend from 6 km for all isotopologues to 75 km for ¹²CH₄, 35 km for CH₃D, and 50 km for ¹³CH₄. While total methane concentrations retrieved from ACE agree well with the model, values of δD-CH₄ and δ¹³C-CH …

Java Based Visualization And Animation For Teaching The Dijkstra Shortest Path Algorithm In Transportation Networks, Ivan Makohon, Duc T. Nguyen, Masha Sosonkina, Yuzhong Shen, Manwo Ng

Civil & Environmental Engineering Faculty Publications

Shortest path (SP) algorithms, such as the popular Dijkstra algorithm has been considered as the "basic building blocks" for many advanced transportation network models. Dijkstra algorithm will find the shortest time (ST) and the corresponding SP to travel from a source node to a destination node. Applications of SP algorithms include real-time GPS and the Frank-Wolfe network equilibrium.

For transportation engineering students, the Dijkstra algorithm is not easily understood. This paper discusses the design and development of a software that will help the students to fully understand the key components involved in the Dijkstra SP algorithm. The software presents an …

Powerforecaster: Predicting Power Impact Of Mobile Sensing Applications At Pre-Installation Time, Chulhong Min, Youngki Lee, Chungkuk Yoo, Seungwoo Kang, Inseok Hwang, Junehwa Song

Research Collection School Of Computing and Information Systems

Today's smartphone application (hereinafter 'app') markets miss a key piece of information, power consumption of apps. This causes a severe problem for continuous sensing apps as they consume significant power without users' awareness. Users have no choice but to repeatedly install one app after another and experience their power use. To break such an exhaustive cycle, we propose PowerForecaster, a system that provides users with power use of sensing apps at pre-installation time. Such advanced power estimation is extremely challenging since the power cost of a sensing app largely varies with users' physical activities and phone use patterns. We observe …

The Onset Of Electron-Induced Proton-Transfer In Hydrated Azabenzene Cluster Anions, Yi Wang, Xinxing Zhang, Svetlana Lyapustina, Michael M. Nilles, Shoujun Xu, Jacob D. Graham, Kit H. Bowen, John T. Kelly, Gregory S. Tschumper, Nathan I. Hammer

Chemistry Faculty Research & Creative Works

The prospect that protons from water may be transferred to N-heterocyclic molecules due to the presence of an excess electron is studied in hydrated azobenzene cluster anions using anion photoelectron spectroscopy and computational chemistry. In the case of s-triazine (C₃H₃N₃), which has a positive adiabatic electron affinity, proton transfer is not energetically favored nor observed experimentally. Heterocyclic rings with only 1 or 2 nitrogen atoms have negative electron affinities, but the addition of solvating water molecules can yield stable negative ions. In the case of the diazines (C₄H₄N₂: …

Sub-Millisecond Response Time In A Photorefractive Composite Operating Under Cw Conditions, Jong-Sik Moon, Tyler E. Stevens, Todd C. Monson, Dale L. Huber, Sung-Ho Jin, Jin-Woo Oh, Jeffrey G. Winiarz

Chemistry Faculty Research & Creative Works

Extensive study of photorefractive polymeric composites photosensitized with semiconductor nanocrystals has yielded data indicating that the inclusion of such nanocrystals enhances the charge-carrier mobility, and subsequently leads to a reduction in the photorefractive response time. Unfortunately, the included nanocrystals may also act as a source of deep traps, resulting in diminished diffraction efficiencies as well as reduced two beam coupling gain coefficients. Nonetheless, previous studies indicate that this problem is mitigated through the inclusion of semiconductor nanocrystals possessing a relatively narrow band-gap. Here, we fully exploit this property by doping PbS nanocrystals into a newly formulated photorefractive composite based on …

The Virtual Atomic And Molecular Data Centre (Vamdc) Consortium, Marie-Lise Dubernet, B. K. Antony, Ernesto Quintas-Sánchez, For Full List Of Authors, See Publisher's Website.

Chemistry Faculty Research & Creative Works

The Virtual Atomic and Molecular Data Centre (VAMDC) Consortium is a worldwide consortium which federates atomic and molecular databases through an e-science infrastructure and an organisation to support this activity. About 90% of the inter-connected databases handle data that are used for the interpretation of astronomical spectra and for modelling in many fields of astrophysics. Recently the VAMDC Consortium has connected databases from the radiation damage and the plasma communities, as well as promoting the publication of data from Indian institutes. This paper describes how the VAMDC Consortium is organised for the optimal distribution of atomic and molecular data for …

A Corpus Of Annotated Irish Traditional Dance Music Recordings: Design And Benchmark Evaluations, Pierre Beauguitte, Bryan Duggan, John D. Kelleher

Conference papers

An emerging trend in music information retrieval (MIR) is the use of supervised machine learning to train automatic music transcription models. A prerequisite of adopting a machine learning methodology is the availability of annotated corpora. However, different genres of music have different characteristics and modelling these characteristics is an important part of creating state of the art MIR systems. Consequently, although some music corpora are available the use of these corpora is tied to the specific music genre, instrument type and recording context the corpus covers. This paper introduces the first corpus of annotations of audio recordings of Irish traditional …

Harnessing The Power Of Text Mining For The Detection Of Abusive Content In Social Media, Hao Chen, Susan Mckeever, Sarah Jane Delany

Conference papers

Abstract The issues of cyberbullying and online harassment have gained considerable coverage in the last number of years. Social media providers need to be able to detect abusive content both accurately and efficiently in order to protect their users. Our aim is to investigate the application of core text mining techniques for the automatic detection of abusive content across a range of social media sources include blogs, forums, media-sharing, Q&A and chat - using datasets from Twitter, YouTube, MySpace, Kongregate, Formspring and Slashdot. Using supervised machine learning, we compare alternative text representations and dimension reduction approaches, including feature selection and …

Assessment Of Measured And Perceived Microclimates Within A Tropical Urban Forest, Winston T. L. Chow, Siti Nur ‘Assyakirin Binte Ali Akbar, Su Li Heng, Matthias Roth

Research Collection School of Social Sciences

Urban greenery is a favoured approach applied towards reducing urban warmth and climate discomfort, but ascertaining its measured and perceived effectiveness in tropical climates is relatively understudied. To this end, we investigated microclimate differences within an urban park (the Singapore Botanic Gardens) to assess if variations in plot-scale land cover affect both objective (measured) and subjective (surveyed) microclimate data. Over two monsoonal seasons, we obtained data from four distinct sites—a tropical rainforest stand, a palm tree valley, a water-body feature, and the park visitors’ centre. Measured climate data (e.g. air temperature, vapour pressure, wind velocity and globe temperatures) were used …

The Von Neumann Inequality For 3 × 3 Matrices, Greg Knese

Mathematics Faculty Publications

This note details how recent work of Kosiński on the three point Pick interpolation problem on the polydisc can be used to prove the von Neumann inequality for d-tuples of commuting 3 x 3 contractive matrices.

Canonical Agler Decompositions And Transfer Function Realizations, Kelly Bickel, Greg Knese

Mathematics Faculty Publications

A seminal result of Agler proves that the natural de Branges-Rovnyak kernel function associated to a bounded analytic function on the bidisk can be decomposed into two shift-invariant pieces. Agler's decomposition is non-constructive—a problem remedied by work of Ball-Sadosky-Vinnikov, which uses scattering systems to produce Agler decompositions through concrete Hilbert space geometry. This method, while constructive, so far has not revealed the rich structure shown to be present for special classes of functions--inner and rational inner functions. In this paper, we show that most of the important structure present in these special cases extends to general bounded analytic functions. We …

Geometric Algorithms For Modeling Protein Structures, Dan Zeng

Undergraduate Research Symposium Posters

Understanding the structures of macromolecular assemblies is necessary to describe the mechanics of a wide variety of cellular processes. Such assemblies often consist of hundreds of proteins and nucleic acid, each with a unique shape. Modern imaging techniques, including electron cryo-microscopy, create 3D density maps to portray the shapes of these assemblies. However, computational methods for deriving structural models from these images are not fully developed because structural geometry varies depending on the image resolution. To address this issue, we developed geometric algorithms in Gorgon, a molecular visualization software. First, we created an interface for Pathwalking. This algorithm determines protein …

Topological Transitions In A Superconducting Qubit, Arman Guerra

Undergraduate Research Symposium Posters

Topology, as it pertains to quantum objects, has become an important area of research because of recent discoveries of topological phases and insulators in condensed matter physics. It can be used as a tool to accurately describe phenomena in many different quantum systems. I present my study of topology as it relates to two level systems, and experiments to probe the topology of transmon qubits. These simple quantum circuits allow for a high level of control which makes them good candidates to study topological properties and to model more complicated systems. Specifically, topological transitions of the first Chern number arise …

Calculating The Observable Properties Of Mass Accreting Black Holes, Heather Lee

Undergraduate Research Symposium Posters

My goal is to generalize Chandrasekhar’s formulas to include partial Rayleigh Scattering. In my summer research, I successfully recalculated key tables and solutions from his book and I am working in generalizing his results for use in an infinitely deep electron atmosphere. Here, I will summarize how Chandrasekhar derived his formulas and how to potentially generalize them to include absorption.

The Challenge Of Blocking Malvertising, Catherine Dwyer, Susanne O'Callaghan, Chinmay Juneja, Preston Rollins, Harpreet Wasan, Ameet Kanguri

Student and Faculty Research Days

This poster invited Research Days attendees to learn more about malvertising--the practice of hiding malicious code within online advertisements--and the challenges of detecting and preventing it.

Food Finder Mobile Application: Reducing Food Wastage And Saving Money Through Mobile Application Technology, Rohana Sosa, Jacob Rein, Jean Coppola

Student and Faculty Research Days

Food Finder is an Android App designed to keep track of the user’s food inventory. Its notable features include, but are not limited to, a barcode scanner, e-mail sharing of data, and being language-neutral. The target audience is universal, with special emphasis on the elderly.

Food Finder was designed to be simple and straightforward to navigate. The user can add items either by keying them in or by scanning the item bar code; items are organized by location, with tabs for refrigerator, freezer, and pantry, as well as a tab for items that they need. The “share” feature allows users …

Is The Time Allocated To Review Patent Applications Inducing Examiners To Grant Invalid Patents?: Evidence From Micro-Level Application Data, Michael D. Frakes, Melissa F. Wasserman

Faculty Scholarship

We explore how examiner behavior is altered by the time allocated for reviewing patent applications. Insufficient examination time may hamper examiner search and rejection efforts, leaving examiners more inclined to grant invalid applications. To test this prediction, we use application-level data to trace the behavior of individual examiners over the course of a series of promotions that carry with them reductions in examination-time allocations. We find evidence demonstrating that such promotions are associated with reductions in examination scrutiny and increases in granting tendencies, as well as evidence that those additional patents being issued on the margin are of below-average quality.

A Fossilized Energy Distribution Of Lightning, Matthew A. Pasek, Marc Hurst

School of Geosciences Faculty and Staff Publications

When lightning strikes soil, it may generate a cylindrical tube of glass known as a fulgurite. The morphology of a fulgurite is ultimately a consequence of the energy of the lightning strike that formed it, and hence fulgurites may be useful in elucidating the energy distribution frequency of cloud-to-ground lightning. Fulgurites from sand mines in Polk County, Florida, USA were collected and analyzed to determine morphologic properties. Here we show that the energy per unit length of lightning strikes within quartz sand has a geometric mean of ~1.0 MJ/m, and that the distribution is lognormal with respect to energy per …

Geochemistry Of Upper Cretaceous Sediments Of Bozeş Formation (Apuseni Mts., Romania) – Provenance Implications, Luminiţa Zaharia, Romona Bălc, Cosmin C. Stremţan, Adriana Socaciu

School of Geosciences Faculty and Staff Publications

A whole-rock geochemical study was carried out on sandstones from the Upper Cretaceous Bozeş Formation in the southeastern part of the Apuseni Mountains (Romania) in order to constrain their provenance and depositional setting. The geochemical results were compared and integrated with previously reported provenance indicators, such as framework composition and heavy mineral assemblages. The chemical composition is similar for all samples investigated, with limited ranges for both major oxides and trace elements. The sandstones are potassic (Na₂O/K₂O < 1) and can be classified mainly as arenites with a few greywackes. Their immature to relatively mature character is revealed by the SiO₂/Al₂O₃ ratios, ranging between 3.90 and 11.25, as well as their high Sr/Rb ratios. The …

Encrustation Of Inarticulate Brachiopods On Scaphitid Ammonites And Inoceramid Bivalves From The Upper Cretaceous U. S. Western Interior, Neil H. Landman, Joshua S. Slattery, Peter J. Harries

School of Geosciences Faculty and Staff Publications

The inarticulate brachiopod Discinisca is a rare faunal element in the Upper Cretaceous of the U.S. Western Interior. We report two occurrences of encrustation of Discinisca on a scaphitid ammonite (scaphite) and several inoceramids from the lower Maastrichtian Baculites baculus/Endocostea typica Biozones of the Pierre Shale at two localities. Six specimens of Discinisca are present on a single specimen of Hoploscaphites crassus from east-central Montana. They occur along the furrow at the mature apertural margin. Because the brachiopods are restricted to the margin and do not occur on the rest of the shell, it is likely that they …