Digital Commons Network^™

Using A Coupled Bio-Economic Model To Find The Optimal Phosphorus Load In Lake Tainter, Wi, Mackenzie Jones

Williams Honors College, Honors Research Projects

In Dunn County, Wisconsin the lakes suffer from algae blooms due to excess phosphorus runoff. A coupled bio-economic model is studied with the intent of finding the optimal level of phosphorus that should be allowed into the lake depending on certain biologic and economic parameters. We model the algae and phosphorus concentration in the lake over time based off the phosphorus input. Community welfare is modeled by comparing the costs and benefits of phosphorus fertilizer. This model is proposed to find the phosphorus level that maximizes community welfare and then determine how certain environmental and social change initiatives will affect …

Two Notes On A Piano, Samuel Thomas

Williams Honors College, Honors Research Projects

In an increasingly digital world, the analog tends to be neglected in exchange for the convenience and precision of digital devices. However, many analog systems exhibit physical phenomena that can be difficult to reproduce digitally. The purpose of this project is to explore the piano and parts of its sonic character that are not currently accounted for in digital systems. Specifically, when multiple notes are being propagated on a soundboard, they affect each other’s tone because each one changes the state of the soundboard. The effect is evident in the partials of each note: the partials (not quite harmonics but …

"Lily-Brick" Peripheral Documents, Benjamin Holda

Williams Honors College, Honors Research Projects

The peripheral analysis of the composition of the novel Lily-Brick, by Ben Holda

Examining The Influence Of Technology Acceptance, Self-Efficacy, And Locus Of Control On Information Security Behavior Of Social Media Users, Abdullah Almuqrin

Master's Theses and Doctoral Dissertations

Due to recent advances in online communication technology, social networks have become a vital avenue for human interaction. At the same time, they have been exploited as a target for viruses, attacks, and security threats. The first line of defense against such attacks and threats— as well as their primary cause—are social media users themselves. This study investigated the relationship between certain personality factors among social media users—i.e., technology acceptance of security protection technologies, self-efficacy of information security, and locus of control—and their information security behavior. Quantitative methods were used to examine this relationship. The population consisted of all students …

Enhanced Control And Reproducibility Of Non-Neutral Plasmas, Timothy Tharp, M. Ahmadi, B. X. R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, M. A. Johnson, S. A. Jones, S. Jonsell, L. Kurchaninov, N. Madsen, M. Mathers, D. Maxwell, J. T. K. Mckenna, S. Menary, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. O. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, C. So, G. Stutter, J. E. Thompson, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele

Physics Faculty Research and Publications

The simultaneous control of the density and particle number of non-neutral plasmas confined in Penning-Malmberg traps is demonstrated. Control is achieved by setting the plasma’s density by applying a rotating electric field while simultaneously fixing its axial potential via evaporative cooling. This novel method is particularly useful for stabilizing positron plasmas, as the procedures used to collect positrons from radioactive sources typically yield plasmas with variable densities and particle numbers; it also simplifies optimization studies that require plasma parameter scans. The reproducibility achieved by applying this technique to the positron and electron plasmas used by the ALPHA antihydrogen experiment at …

A Culturally Tailored Intervention System For Cancer Survivors To Motivate Physical Activity, Golam Mushih Tanimul Ahsan, Jannatul F. Tumpa, Riddhiman Adib, Sheikh Iqbal Ahamed, Daniel Petereit, Linda Burhansstipanov, Linda U. Krebs, Mark Dignan

Computer Science Faculty Research and Publications

It is necessary for a cancer survivor to have good health behavior. Essential exercise and proper diet are helpful to decrease the risk of recurrence of the disease and the development of a new cancer type. People from low socioeconomic status are more likely to participate in risky health behaviors and have a higher chance of recurrence of cancer. It is important to have a motivational system for cancer survivors that motivates them to perform regular physical activities. In this article, we discuss the development of an mHealth system, which aims to increase physical activity in Native American populations with …

Salt Retention In Wetland Soils And Effects On Dissolved Organic Carbon Export, Kayla Marie Mcguire

Master's Theses and Doctoral Dissertations

Deicing salt runoff has negative effects on ecosystems. Wetland ecosystems can act as important filters for runoff pollution (e.g., nutrients), mitigating damage to plants and microbes. Wetlands are important sinks for nutrients and pollutants (e.g., road salt) and transformation spots for many nutrients including carbon. The interactions between deicing salt runoff and wetland soil carbon were explored by measuring chloride export and retention, dissolved organic carbon (DOC) export, and carbon quality using mesocosm experiments. Net retention of Cl- was highest in soils receiving high salt treatments (5.0 g/L NaCl), although percent retention of Cl- was greater in soils receiving moderate …

[Introduction To] Finite Blaschke Products And Their Connections, Stephan Ramon Garcia, Javad Mashreghi, William T. Ross

Bookshelf

This monograph offers an introduction to finite Blaschke products and their connections to complex analysis, linear algebra, operator theory, matrix analysis, and other fields. Old favorites such as the Carathéodory approximation and the Pick interpolation theorems are featured, as are many topics that have never received a modern treatment, such as the Bohr radius and Ritt's theorem on decomposability. Deep connections to hyperbolic geometry are explored, as are the mapping properties, zeros, residues, and critical points of finite Blaschke products. In addition, model spaces, rational functions with real boundary values, spectral mapping properties of the numerical range, and the Darlington …

Strength Of Π-Stacking, From Neutral To Cation: Precision Measurement Of Binding Energies In An Isolated Π-Stacked Dimer, Damian Kokkin, Maxim V. Ivanov, John Loman, Jin-Zhe Cai, Rajendra Rathore, Scott A. Reid

Chemistry Faculty Research and Publications

π-Stacking interactions are ubiquitious across chemistry and biochemistry, impacting areas from organic materials and photovoltaics to biochemistry and DNA. However, experimental data is lacking regarding the strength of π-stacking forces—an issue not settled even for the simplest model system, the isolated benzene dimer. Here, we use two-color appearance potential measurements to determine the binding energies of the isolated, π-stacked dimer of fluorene (C₁₃H₁₀) in ground, excited, and ionic states. Our measurements provide the first precise values for π-stacking interaction energies in these states, which are key benchmarks for theory. Indeed, theoretical predictions using ab initio and …

Structural Evidence Of A Major Conformational Change Triggered By Substrate Binding In Dape Enzymes: Impact On The Catalytic Mechanism, Boguslaw P. Nocek, Cory Reidl, Anna Starus, Tahirah Heath, David L. Bienvenue, Jerzy Osipiuk, Robert Jedrzejczak, Andzrej Joachimiak, Daniel P. Becker, Richard C. Holz

Chemistry Faculty Research and Publications

The X-ray crystal structure of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase from Haemophilus influenzae (HiDapE) bound by the products of hydrolysis, succinic acid and l,l-DAP, was determined at 1.95 Å. Surprisingly, the structure bound to the products revealed that HiDapE undergoes a significant conformational change in which the catalytic domain rotates ∼50° and shifts ∼10.1 Å (as measured at the position of the Zn atoms) relative to the dimerization domain. This heretofore unobserved closed conformation revealed significant movements within the catalytic domain compared to that of wild-type HiDapE, which results in effectively closing off access to …

Fhbc, A Hexa‐Peri‐Hexabenzocoronene–Fluorene Hybrid: A Platform For Highly Soluble, Easily Functionalizable Hbcs With An Expanded Graphitic Core, Tushar S. Navale, Maxim V. Ivanov, Mohammad M. Hossain, Rajendra Rathore

Chemistry Faculty Research and Publications

Materials based upon hexa‐peri‐hexabenzocoronenes (HBCs) show significant promise in a variety of photovoltaic applications. There remains the need, however, for a soluble, versatile, HBC‐based platform, which can be tailored by incorporation of electroactive groups or groups that can prompt self‐assembly. The synthesis of a HBC–fluorene hybrid is presented that contains an expanded graphitic core that is highly soluble, resists aggregation, and can be readily functionalized at its vertices. This new HBC platform can be tailored to incorporate six electroactive groups at its vertices, as exemplified by a facile synthesis of a representative hexaaryl derivative of FHBC. Synthesis of …

Human P450 Cyp17a1: Control Of Substrate Preference By Asparagine 202, Michael C. Gregory, Piotr J. Mak, Yogan Khatri, James R. Kincaid, Stephen G. Sligar

Chemistry Faculty Research and Publications

CYP17A1 is a key steroidogenic enzyme known to conduct several distinct chemical transformations on multiple substrates. In its hydroxylase activity, this enzyme adds a hydroxyl group at the 17α position of both pregnenolone and progesterone at approximately equal rates. However, the subsequent 17,20 carbon–carbon scission reaction displays variable substrate specificity in the numerous CYP17A1 isozymes operating in vertebrates, manifesting as different K_d and k_cat values when presented with 17α-hydroxypregnenlone (OHPREG) versus 17α-hydroxyprogesterone (OHPROG). Here we show that the identity of the residue at position 202 in human CYP17A1, thought to form a hydrogen bond with the A-ring alcohol …

The Efficacy Of Commercial Tooth Storage Media For Maintaining The Viability Of Human Periodontal Ligament Fibroblasts, W. Lee, Sheila E. Stover, Morteza Rasoulianboroujeni, K. Sherman, Farahnaz Fahimipour, E. Dashtimoghadam, C. Zito, Hossein E. Jazayeri, Lobat Tayebi

School of Dentistry Faculty Research and Publications

Aim

To evaluate Save‐A‐Tooth (SAT), EMT Toothsaver (EMT) and Hank's Balanced Salt Solution (HBSS) for their influence on the viability and proliferative capacity of human periodontal ligament fibroblasts (HPDLFs).

Methodology

Primary HPDLFs were seeded into 96‐well cell culture plates and exposed to SAT, EMT, HBSS and water (negative control) for 0.5, 1, 3, 6, 12 and 24 h at room temperature (22 °C). After each exposure time, cell viability was measured through quantifying adenosine triphosphate (ATP) using a luminescent dye. The proliferative capacity was also quantified using the PrestoBlue assay after 12 or 24 h storage in each medium. The …

Development Of Chitosan/Gelatin/Keratin Composite Containing Hydrocortisone Sodium Succinate As A Buccal Mucoadhesive Patch To Treat Desquamative Gingivitis, Zahra Davoudi, Mohammad Rabiee, Behzad Houshmand, Niloofar Eslahi, Kimia Khoshroo, Morteza Rasoulianboroujeni, Mohammadreza Tahriri, Lobat Tayebi

School of Dentistry Faculty Research and Publications

The aim of this research was to develop chitosan/gelatin/keratin composite containing hydrocortisone sodium succinate as a buccal mucoadhesive patch to treat desquamative gingivitis, which was fabricated through an environmental friendly process. Mucoadhesive films increase the advantage of higher efficiency and drug localization in the affected region. In this research, mucoadhesive films, for the release of hydrocortisone sodium succinate, were prepared using different ratios of chitosan, gelatin and keratin. In the first step, chitosan and gelatin proportions were optimized after evaluating the mechanical properties, swelling capacity, water uptake, stability, and biodegradation of the films. Then, keratin was added at different percentages …

Several Levels Of Theory For Description Of Isotope Effects In Ozone: Symmetry Effect And Mass Effect, Alexander Teplukhin, Dmitri Babikov

Chemistry Faculty Research and Publications

The essential components of theory for the description of isotope effects in recombination reaction that forms ozone are presented, including the introduction of three reaction pathways for symmetric and asymmetric isotopomers, a brief review of relevant experimental data for singly- and doubly substituted isotopologues, the definitions of ζ-effect and η-effect, and the introduction of isotopic enrichment δ. Two levels of theory are developed to elucidate the role of molecular symmetry, atomic masses, vibrational zero-point energies, and rotational excitations in the recombination process. The issue of symmetry is not trivial, since the important factors, such as 1/2 and 2, appear in …

Quantum Dynamics Of Isolated Molecules: General Discussion, Dmitri Babikov, David Benoit, Joel Bowman, Timothy Burd, David Clary, Robert Donovan, Ingo Fischer, Francesco Gianturco, Majdi Hochlaf, Susmita Kar, Adam Kirrander, Stephen Leone, Thomas Malcomson, Uwe Manthe, Anne B. Mccoy, Jens Petersen, Jeremy Richardson, Petr Slavíček, Thierry Stoecklin, Krzysztof Szalewicz, Ad Van Der Avoird, Roland Wester, Graham Worth, Anne Zehnacker-Rentien

Chemistry Faculty Research and Publications

No abstract provided.

Selection And Implementation Of Skill Acquisition Programs By Special Education Teachers And Staff For Students With Autism Spectrum Disorder, Tiffany Kodak, Tom Cariveau, Brittany A. Leblanc

Psychology Faculty Research and Publications

The present investigation examined special education teachers’ selection and use of teaching strategies for receptive identification training with children with autism spectrum disorder (ASD) in their classrooms. Teachers first responded to a survey in which they provided examples of receptive identification tasks taught in their classrooms, rated the efficacy of teaching strategies, described how they determined whether skills were mastered, listed any assessments they conducted to identify relevant prerequisite skills prior to receptive identification training, described how they selected teaching strategies for use in their classrooms, and listed their years of experience as a teacher and working with children with …

Book Review Of The Basics Of Item Response Theory Using R, Brooke E. Magnus

Psychology Faculty Research and Publications

This article reviews the book The Basics of Item Response Theory Using R by Baker and Kim (2017). It describes the structure and goals of the book, provides an overview of each chapter, and concludes with general comments. Both strengths and limitations of the book are discussed.

Resource Extraction And Infrastructure Threaten Forest Cover And Community Rights, Anthony J. Bebbington, Denise Humphreys Bebbington, Laura Aileen Sauls, John Rogan, Sumali Agrawal, César Gamboa, Aviva Imhof, Kimberly Johnson, Herman Rosa, Antoinette Royo, Tessa Toumbourou, Ricardo Verdum

Geography

Mineral and hydrocarbon extraction and infrastructure are increasingly significant drivers of forest loss, greenhouse gas emissions, and threats to the rights of forest communities in forested areas of Amazonia, Indonesia, and Mesoamerica. Projected investments in these sectors suggest that future threats to forests and rights are substantial, particularly because resource extraction and infrastructure reinforce each other and enable population movements and agricultural expansion further into the forest. In each region, governments have made framework policy commitments to national and cross-border infrastructure integration, increased energy production, and growth strategies based on further exploitation of natural resources. This reflects political settlements among …

The Infrastructure-Extractives-Resource Governance Complex In The Pan-Amazon: Roll Backs And Contestations, Denise Bebbington, Ricardo Verdum, Cesar Gamboa, Anthony J. Bebbington

Geography

Large-scale access and energy infrastructure projects, together with expanding investments in natural resource extraction, pose significant challenges to biodiversity conservation, forest cover, and the defence of forest peoples' rights and livelihoods across the wider Amazon region. Following a period in which safeguards and forest dwellers' territorial rights were strengthened under more permissive political opportunity structures, the current period has been characterized by efforts to weaken these protections and to facilitate large-scale private investment in previously protected lands. We describe these investment-based threats to forests and rights, and the nature of regulatory rollbacks in the region. We then discuss some of …

Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D’Amato, Tiphaine Després, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Álvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, Thomas Kitzberger, Dominik Kulakowski, David Lindenmayer, Akira S. Mori, Jörg Müller, Juan Paritsis, George L.W. Perry, Scott L. Stephens, Miroslav Svoboda, Monica G. Turner, Thomas T. Veblen, Rupert Seidl

Geography

Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and …

Trends In Benthic Macrofaunal Populations, Seasonal Sea Ice Persistence, And Bottom Water Temperatures In The Bering Strait Region, Jacqueline M. Grebmeier, Karen E. Frey, Lee W. Cooper, Monika Kędra

Geography

Recent declines in sea ice extent and warming seawater temperatures in the Arctic have the potential to impact regional and pan-Arctic marine ecosystems. To investigate marine biological response to these key drivers and other environmental factors, we undertook a robust trend analysis of benthic macrofaunal populations and environmental drivers in the Bering Strait region. Our focus was on the waters of the northern Bering and southern Chukchi Seas, which are shallow (m) and seasonally productive, with strong pelagic-benthic coupling between water-column-derived organic matter and the seafloor. Studies indicate that both in situ production and advection of upstream phytodetritus support persistent …

(Un)Frozen Spaces: Exploring The Role Of Sea Ice In The Marine Socio-Legal Spaces Of The Bering And Beaufort Seas, Kristen L. Shake, Karen E. Frey, Deborah G. Martin, Philip E. Steinberg

Geography

Sea ice is a dynamic physical element of the greater Arctic marine system, one that has myriad connections to human systems on a variety of spatial and temporal scales. Changes to the spatial extent of sea ice simultaneously permits and endangers maritime operations, as well as impacts current debates over maritime boundaries, presenting an interesting challenge for international law. Sea ice is not a stationary object; it moves through time and space in response to the physical forces of wind, ocean currents, and heating. It has a tangible, material and substantive role in contestations over territory, resources and marine boundaries …

Digitalized Cognitive Assessment Mediated By A Virtual Caregiver, Matteo Luperto, Marta Romeo, Francesca Lunardini, Nicola Basilico, Ray Jones, Angelo Cangelosi, Simona Ferrante, Na Borghese

School of Nursing and Midwifery

The ageing of the population deeply impacts on the social costs relative to health care. The use of modern technologies is one of the most promising approaches, under current study, to reduce such impact. In this demonstration, we propose a framework that can be employed for at-home assessment of Mild Cognitive Impairment (MCI). It is composed by a set of digitalized cognitive tests, developed from their paper-and-pencil counterparts, and by a Virtual Caregiver, which oversees the test execution and provides instructions.

Executive Functioning Strength As A Predictor For Multitasking Performance, Kaitlin M. Reitz

Undergraduate Theses and Senior Projects

No abstract provided.

Nonlinear Coupled Effects In Nanomaterials, Sia Bhowmick

Theses and Dissertations (Comprehensive)

Materials at the nanoscale have different chemical, structural, and optoelectrical properties compared to their bulk counterparts. As a result, such materials, called nanomaterials, exhibit observable differences in certain physical phenomena. One such resulting phenomenon called the piezoelectric effect has played a crucial role in miniature self-powering electronic devices called nanogenerators which are fabricated by using nanostructures, such as nanowires, nanorods, and nanofilms. These devices are capable of harvesting electrical energy by inducing mechanical strain on the individual nanostructures. Electrical energy created in this manner does not have environmental limitations. In this thesis, important coupled effects, such as the nonlinear piezoelectric …

Abelian Subalgebras Of Maximal Dimension In Euclidean Lie Algebras, Mark Curro

Theses and Dissertations (Comprehensive)

In this paper we define, discuss and prove the uniqueness of the abelian subalgebra of maximal dimension of the Euclidean Lie algebra. We also construct a family of maximal abelian subalgebras and prove that they are maximal.

Permafrost Thaw-Induced Forest To Wetland Conversion: Potential Impacts On Snowmelt And Basin Runoff In Northwestern Canada, Emily Haughton

Theses and Dissertations (Comprehensive)

In the discontinuous permafrost zone of northwestern Canada, snow covers the ground surface for over half the year, thus snowmelt constitutes a primary source of ecosystem moisture supply and strongly influences stream hydrographs. The peat landscapes along the southern limit of discontinuous permafrost are dominated by forested permafrost plateaus (“forest”), and treeless, permafrost-free wetlands (“wetland”). Permafrost-thaw induced transformation of this landscape has changed water flow and storage processes and therefore introduced new uncertainties on the region’s water futures. Here, I a) characterize forest and wetland water storage and flow from snowmelt, and b) evaluate how permafrost thaw-induced wetland expansion at …

Testing The Network Reset Hypothesis: Noradrenergic Modulation Of Hippocampal Representations, Stephanie L. Grella

Theses and Dissertations (Comprehensive)

The locus coeruleus (LC) responds to salience cues, including novelty, and sends a major noradrenergic projection to the hippocampal formation (HF). Novelty-associated LC activation may help to sculpt contextual representations in the HF, but modulatory influence of norepinephrine (NE) over HF representations remains poorly understood. One possible mechanism is that NE provides a “reset” signal causing the HF to recruit distinct neural populations, thereby providing a molecular switch to dictate if hippocampal circuits should generate new representations or update existing ones to incorporate novel information. This hypothesis suggests that NE release should cause the HF to recruit a unique population …

Spatial And Temporal Variability Of The Snow Environment In The Western Canadian Arctic, Philip Mann

Theses and Dissertations (Comprehensive)

Snow cover in the Western Canadian Arctic is a significant input to the hydrological mass balance, it produces shelter and habitat for animals and humans, and supports interactions with vegetation and climate. The Arctic-tundra snow cover is greatly impacted by wind erosion, redistribution and deposition of snow during high wind events over the winter months. As a result, the end of winter snow cover is characterised by significant small-scale (on the order of a few meters) spatial variations in snow cover depth, density, and thus snow water equivalent (SWE), and runoff. Future climate related changes to snow cover depth and …