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2018

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Articles 12931 - 12960 of 13645

Full-Text Articles in Physical Sciences and Mathematics

Cyber Security And Risk Society: Estonian Discourse On Cyber Risk And Security Strategy, Lauren Kook Jan 2018

Cyber Security And Risk Society: Estonian Discourse On Cyber Risk And Security Strategy, Lauren Kook

Copyright, Fair Use, Scholarly Communication, etc.

The main aim of this thesis is to call for a new analysis of cyber security which departs from the traditional security theory. I argue that the cyber domain is inherently different in nature, in that it is lacking in traditional boundaries and is reflexive in nature. Policy-makers are aware of these characteristics, and in turn this awareness changes the way that national cyber security strategy is handled and understood. These changes cannot be adequately understood through traditional understanding of security, as they often are, without missing significant details. Rather, examining these changes through the lens of Ulrich Beck’s risk …


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

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

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

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


Review: The Use Of Real-Time Fluorescence Instrumentation To Monitor Ambient Primary Biological Aerosol Particles (Pbap), Gavin Sewell, David O'Connor, Michael J. Fennelly, Michael B. Prentice, John R. Sodeau Jan 2018

Review: The Use Of Real-Time Fluorescence Instrumentation To Monitor Ambient Primary Biological Aerosol Particles (Pbap), Gavin Sewell, David O'Connor, Michael J. Fennelly, Michael B. Prentice, John R. Sodeau

Articles

Primary biological aerosol particles (PBAP) encompass many particle types that are derived from several biological kingdoms. These aerosol particles can be composed of both whole living units such as pollen, bacteria, and fungi, as well as from mechanically formed particles, such as plant debris. They constitute a significant proportion of the overall atmospheric particle load and have been linked with adverse health issues and climatic effects on the environment. Traditional methods for their analysis have focused on the direct capture of PBAP before subsequent laboratory analysis. These analysis types have generally relied on direct optical microscopy or incubation on agar …


Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr. Jan 2018

Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Climate variability at global and regional scales is escalating with increased atmospheric carbon and is expected to magnify the intensity and duration of meteorological extremes, especially droughts. From the many environmental stresses that diminish crop production (e.g., soil salinity, frost, soil erosion) drought is one of the most prevalent. This study focuses on the sensitivity of three key crops produced in the northwestern United States to climatological anomalies, while controlling for attribution using anomalies in price. The study differs from similar studies in that we focus on variability in production which captures both yield (tonnes/ha) and cropping area (ha), as …


Estimating Groundwater Inflow And Age Characteristics In An Alluvial Aquifer Along The Little Wind River, Wyoming, Derek Goble Jan 2018

Estimating Groundwater Inflow And Age Characteristics In An Alluvial Aquifer Along The Little Wind River, Wyoming, Derek Goble

Graduate Student Theses, Dissertations, & Professional Papers

We synoptically sampled a 2 km gaining reach of the Little Wind River in central Wyoming for 222Rn, CFCs and SF6 to determine the distributed volumes and locations of discharge and estimate alluvial groundwater age characteristics. 222Rn was sampled in the stream, shallow in-stream piezometers and nearby alluvial groundwater wells to determine the volume and spatial distribution of groundwater discharge to the river. Age tracers, CFC and SF6, sampled in the stream, shallow in-stream piezometers and in alluvial groundwater wells were then used to determine whether in-stream samples are capable of constraining the residence time distribution …


Mountain Pine Beetle Induced Changes To Lodgepole Pine Forest Stand Dynamics At Lubrecht Experimental Forest, Ben G. O'Connor Jan 2018

Mountain Pine Beetle Induced Changes To Lodgepole Pine Forest Stand Dynamics At Lubrecht Experimental Forest, Ben G. O'Connor

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.


Dynamic Control Of Particle Separation In Deterministic Lateral Displacement Separator With Viscoelastic Fluids, Yuke Li, Hongna Zhang, Yongyao Li, Xiaobin Li, Jian Wu, Shizhi Qian, Fengchen Li Jan 2018

Dynamic Control Of Particle Separation In Deterministic Lateral Displacement Separator With Viscoelastic Fluids, Yuke Li, Hongna Zhang, Yongyao Li, Xiaobin Li, Jian Wu, Shizhi Qian, Fengchen Li

Mechanical & Aerospace Engineering Faculty Publications

We proposed an innovative method to achieve dynamic control of particle separation by employing viscoelastic fluids in deterministic lateral displacement (DLD) arrays. The effects of shear-thinning and elasticity of working fluids on the critical separation size in DLD arrays are investigated. It is observed that each effect can lead to the variation of the critical separation size by approximately 40%. Since the elasticity strength of the fluid is related to the shear rate, the dynamic control can for the first time be easily realized through tuning the flow rate in microchannels.


New Dimensions For A Challenging Security Environment: Growing Exposure To Critical Space Infrastructure Disruption Risk, Adrian V. Gheorghe, Alexandru Georgescu, Olga Bucovetchi, Marilena Lazăr, Cezar Scarlat Jan 2018

New Dimensions For A Challenging Security Environment: Growing Exposure To Critical Space Infrastructure Disruption Risk, Adrian V. Gheorghe, Alexandru Georgescu, Olga Bucovetchi, Marilena Lazăr, Cezar Scarlat

Engineering Management & Systems Engineering Faculty Publications

Space systems have become a key enabler for a wide variety of applications that are vital to the functioning of advanced societies. The trend is one of quantitative and qualitative increase of this dependence, so much so that space systems have been described as a new example of critical infrastructure. This article argues that the existence of critical space infrastructures implies the emergence of a new category of disasters related to disruption risks. We inventory those risks and make policy recommendations for what is, ultimately, a resilience governance issue.


Impacts Of Vegetation Growth On Reach-Scale Flood Hydraulics In A Sand-Bed River And The Implications For Vegetation-Morphology Coevolution, Samuel Box Jan 2018

Impacts Of Vegetation Growth On Reach-Scale Flood Hydraulics In A Sand-Bed River And The Implications For Vegetation-Morphology Coevolution, Samuel Box

Graduate Student Theses, Dissertations, & Professional Papers

Vegetation affects river morphology via plant effects on the flow field, sediment transport and deposition, and substrate erodibility. Changes in the flow field caused by above-ground biomass mediate geomorphic response to flooding and habitat suitability for vegetation growth. Using numerical hydraulic models that incorporate drag due to spatially heterogeneous vegetation, I quantify how changes in the antecedent characteristics of woody vegetation in the active channel lead to changes in local bed shear stress, reach-average bed shear stress, and the vegetative component of reach-average total shear stress. Flood hydraulics in turn affect channel morphology and vegetation, providing a feedback mechanism by …


Home Is Where The Food Is: Causes And Consequences Of Partial Migration In Elk, Kristin Jennifer Barker Jan 2018

Home Is Where The Food Is: Causes And Consequences Of Partial Migration In Elk, Kristin Jennifer Barker

Graduate Student Theses, Dissertations, & Professional Papers

Migratory and non-migratory ungulates often coexist in partially migratory populations, but the mechanisms that drive and maintain different migratory behaviors within the same herd are poorly understood. In western North America, increasing numbers of elk (Cervus canadensis) reside on low-elevation winter range year-round. These residents can cause issues associated with crop damage, potential for disease transmission to livestock, and reduced effectiveness of harvest management strategies. Because migrants transfer nutrients, alter carnivore distributions, and structure vegetative communities across seasonal ranges, reductions in migratory behavior raise ecological as well as management-related concerns. This work investigated the factors affecting migratory behavior …


Economics-Based Risk Management Of Distributed Denial Of Service Attacks: A Distance Learning Case Study, Omer Keskin, Unal Tatar, Omer Poyraz, Ariel Pinto, Adrian Gheorghe Jan 2018

Economics-Based Risk Management Of Distributed Denial Of Service Attacks: A Distance Learning Case Study, Omer Keskin, Unal Tatar, Omer Poyraz, Ariel Pinto, Adrian Gheorghe

Engineering Management & Systems Engineering Faculty Publications

Managing risk of cyber systems is still on the top of the agendas of Chief Information Security Officers (CISO). Investment in cybersecurity is continuously rising. Efficiency and effectiveness of cybersecurity investments are under scrutiny by boards of the companies. The primary method of decision making on cybersecurity adopts a risk-informed approach. Qualitative methods bring a notion of risk. However, particularly for strategic level decisions, more quantitative methods that can calculate the risk and impact in monetary values are required. In this study, a model is built to calculate the economic value of business interruption during a Distributed Denial-of-Service (DDoS) attack …


An Attribute Agreement Method For Hfacs Inter-Rater Reliability Assessment, Teddy Steven Cotter, Veysel Yesilbas Jan 2018

An Attribute Agreement Method For Hfacs Inter-Rater Reliability Assessment, Teddy Steven Cotter, Veysel Yesilbas

Engineering Management & Systems Engineering Faculty Publications

Inter-rater reliability can be regarded as the degree of agreement among raters on a given item or a circumstance. Multiple approaches have been taken to estimate and improve inter-rater reliability of the United States Department of Defense Human Factors Analysis and Classification System used by trained accident investigators. In this study, three trained instructor pilots used the DoD-HFACS to classify 347 U.S. Air Force Accident Investigation Board (AIB) Class-A reports between the years of 2000 and 2013. The overall method consisted of four steps: (1) train on HFACS definitions, (2) verify rating reliability, (3) rate HFACS reports, and (4) random …


A Proposed Taxonomy For The Systems Statistical Engineering Body Of Knowledge, Teddy Steven Cotter Jan 2018

A Proposed Taxonomy For The Systems Statistical Engineering Body Of Knowledge, Teddy Steven Cotter

Engineering Management & Systems Engineering Faculty Publications

In the ASEM-IAC 2012, Cotter (2012) identified the gaps in knowledge that statistical engineering needs to address, explored additional gaps in knowledge not addressed in the prior works, and set forth a working definition of and body of knowledge for statistical engineering. In the ASEM-IAC 2015, Cotter (2015) proposed a systemic causal Bayesian hierarchical model that addressed the knowledge gap needed to integrate deterministic mathematical engineering causal models within a stochastic framework. Missing, however, is the framework for specifying the hierarchical qualitative systems structures necessary and sufficient for specifying systemic causal Bayesian hierarchical models. In the ASEM-IAC 2016, Cotter (2016) …


Research Agenda In Developing Core Reference Ontology For Human Intelligence/Machine-Intelligence Electronic Medical Records System, Ziniya Zahedi, Teddy Steven Cotter Jan 2018

Research Agenda In Developing Core Reference Ontology For Human Intelligence/Machine-Intelligence Electronic Medical Records System, Ziniya Zahedi, Teddy Steven Cotter

Engineering Management & Systems Engineering Faculty Publications

Beginning around 1990, efforts were initiated in the medical profession by the U.S. government to transition from paper based medical records to electronic medical records (EMR). By the late 1990s, EMR implementation had already encountered multiple barriers and failures. Then President Bush set forth the goal of implementing electronic health records (EHRs), nationwide within ten years. Again, progress toward EMR implementation was not realized. President Obama put new emphasis on promoting EMR and health care technology. The renewed emphasis did not overcome many of the original problems and induced new failures. Retrospective analyses suggest that failures were induced because programmers …


Identification Of 4-Isopropyl–Thiotropolone As A Novel Anti-Microbial: Regioselective Synthesis, Nmr Characterization, And Biological Evaluation, Mohamed Elagawany, Mohamed Elagawany, Lamees Hegazy, Feng Cao, Maureen Donlin, Nigam Rath, John Tavis, Bahaa Elgendy, Bahaa Elgendy Jan 2018

Identification Of 4-Isopropyl–Thiotropolone As A Novel Anti-Microbial: Regioselective Synthesis, Nmr Characterization, And Biological Evaluation, Mohamed Elagawany, Mohamed Elagawany, Lamees Hegazy, Feng Cao, Maureen Donlin, Nigam Rath, John Tavis, Bahaa Elgendy, Bahaa Elgendy

Chemistry & Biochemistry Faculty Works

We have synthesized and separated tosylated thujaplicin isomers for the first time, and elucidated their structures using 1D, 2D-NMR techniques and X-ray crystallography. The tosylated isomers were used to synthesize 4-isopropyl–thiotropolone and 6-isopropyl–thiotropolone in a regioselective manner. 1H and 13C Chemical shifts of synthesized isomers were fully assigned using several NMR experiments, and their isotropic magnetic shielding was calculated using the GIAO (Gauge Including Atomic Orbitals) method and the B3LYP def2-TZVPP level of theory. The calculated chemical shift values were in a good agreement with the experimental results. The biological activity of all synthesized compounds was evaluated against the fungal …


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

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

Physics and Astronomy Faculty Publications and Presentations

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


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

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

Physics and Astronomy Faculty Publications and Presentations

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


Rethinking The Teaching And Learning Of Area Measurement, Nicole Panorkou Jan 2018

Rethinking The Teaching And Learning Of Area Measurement, Nicole Panorkou

Department of Mathematics Facuty Scholarship and Creative Works

This study focused on exploring an innovative way of teaching and learning measurement, what we refer to as Dynamic Measurement or DYME. Without relying on the common approach of counting square units, our goal was to engage students in contextually rich digital dynamic tasks to visualize area as a continuous quantity and evaluate the area of a rectangular region as a multiplicative relationship between the two lengths of the sides. In this paper, we briefly describe the iterative process of designing, testing and refining the tasks for DYME pointing to the significance of the design for developing students’ thinking of …


Interlace Polynomials Of Friendship Graphs, Christina Eubanks-Turner, Aihua Li Jan 2018

Interlace Polynomials Of Friendship Graphs, Christina Eubanks-Turner, Aihua Li

Department of Mathematics Facuty Scholarship and Creative Works

In this paper, we study the interlace polynomials of friendship graphs, that is, graphs that satisfy the Friendship Theorem given by Erdös, Rényi and Sos. Explicit formulas, special values, and behaviour of coefficients of these polynomials are provided. We also give the interlace polynomials of other similar graphs, such as, the butterfly graph.


A Covariational Understanding Of Function: Putting A Horse Before The Cart, Teo Paoletti, Kevin C. Moore Jan 2018

A Covariational Understanding Of Function: Putting A Horse Before The Cart, Teo Paoletti, Kevin C. Moore

Department of Mathematics Facuty Scholarship and Creative Works

Supporting students developing understandings of function has been a notoriously elusive task in mathematics education. We present Thompson and Carlson’s (2017) description of a covariational meaning of function and provide an example of a student who maintains meanings compatible with this description. We use this student’s activity to illustrate nuances in a covariational meaning of function and to highlight how such meanings can be powerful for students. In doing so, we argue that a student who has develop meanings compatible with the covariational meaning of function presented by Thompson and Carlson has the foundational meanings needed to understand a formal …


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

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

Physics and Astronomy Faculty Publications and Presentations

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


A Computational Introduction To Elliptic And Hyperelliptic Curve Cryptography, Nicholas Wilcox Jan 2018

A Computational Introduction To Elliptic And Hyperelliptic Curve Cryptography, Nicholas Wilcox

Honors Papers

At its core, cryptography relies on problems that are simple to construct but difficult to solve unless certain information (the “key”) is known. Many of these problems come from number theory and group theory. One method of obtaining groups from which to build cryptosystems is to define algebraic curves over finite fields and then derive a group structure from the set of points on those curves. This thesis serves as an exposition of Elliptic Curve Cryptography (ECC), preceded by a discussion of some basic cryptographic concepts and followed by a glance into one generalization of ECC: cryptosystems based on hyperelliptic …


Heterobifunctional Linear Dendritic Block Co-Polymers (Ldbcs) As Multifunctional Carriers For Targeted Drug Delivery, William Rieger Jan 2018

Heterobifunctional Linear Dendritic Block Co-Polymers (Ldbcs) As Multifunctional Carriers For Targeted Drug Delivery, William Rieger

Honors Theses

Despite current research towards applications of polymeric drug delivery systems (DDSs) in biomedical research, significant limitations—specifically in synthetic accessibility, bio compatibility, and principles of molecular self-assembly—have been discerned. To address these drawbacks, we will investigate the synthesis and characterization of heterobifunctional linear-dendritic block copolymers (LDBCs), which combine the advantageous properties of both linear and dendritic blocks to afford nanomaterials with superior mechanical properties. Our LDBC systems contain two differing functional constituents, namely a hydrophilic polyamidoamine (PAMAM) dendron covalently linked to a hydrophobic polyester (polylactic acid, or PLA), and can self-assemble to form nanoparticles of various morphologies that serve as the …


Information Hiding Using Convolutional Encoding, Jonathan Blackledge, Paul Tobin, J. Myeza, C. M. Adolfo Jan 2018

Information Hiding Using Convolutional Encoding, Jonathan Blackledge, Paul Tobin, J. Myeza, C. M. Adolfo

Conference papers

We consider two functions f1(r) and f2(r), for r 2 Rn and the problem of ‘Diffusing’ these functions together, followed by the application of an encryption process we call ‘Stochastic Diffusion’ and then hiding the output of this process in to one or other of the same functions. The coupling of these two processes (i.e., data diffusion and stochastic diffusion) is considered using a form of conditioning that generates a wellposed and data consistent inverse solution for the purpose of decrypting the output. After presenting the basic encryption method and (encrypted) information hiding model, coupled with a mathematical analysis (within …


The Progressive Evolution Of The Champlain Thrust Fault Zone: Insights From A Structural Analysis Of Its Architecture, Matthew Merson Jan 2018

The Progressive Evolution Of The Champlain Thrust Fault Zone: Insights From A Structural Analysis Of Its Architecture, Matthew Merson

Graduate College Dissertations and Theses

Near Burlington, Vermont, the Champlain Thrust fault placed massive Cambrian dolostones over calcareous shales of Ordovician age during the Ordovician Taconic Orogeny. Although the Champlain Thrust has been studied previously throughout the Champlain Valley, the architecture and structural evolution of its fault zone have never been systematically defined. To document these fault zone characteristics, a detailed structural analysis of multiple outcrops was completed along a 51 km transect between South Hero and Ferrisburgh, Vermont.

The Champlain Thrust fault zone is predominately within the footwall and preserves at least four distinct events that are heterogeneous is both style and slip direction. …


Governing Environmental And Economic Flows In Regional Food Systems, Michael Bishop Wironen Jan 2018

Governing Environmental And Economic Flows In Regional Food Systems, Michael Bishop Wironen

Graduate College Dissertations and Theses

Globalization, specialization, and intensification have transformed the global food system, generating material flows and impacts that span multiple scales and levels, presenting novel governance challenges. Many argue for a transition toward a sustainable food system, although the scope and specific goals are fiercely contested. Theory and method is needed to evaluate competing normative claims and build legitimacy.

In this dissertation Vermont serves as a case study to investigate how environmental and economic flows impact regional governance, focusing on efforts to manage agricultural phosphorus to achieve water quality goals. A material flow account is developed to estimate phosphorus flows embedded in …


Applying Bayesian Belief Network To Understand Public Perception On Green Stormwater Infrastructures In Vermont, Qing Ren Jan 2018

Applying Bayesian Belief Network To Understand Public Perception On Green Stormwater Infrastructures In Vermont, Qing Ren

Graduate College Dissertations and Theses

Decisions of adopting best management practices made on residential properties play an important role in reduction of nutrient loading from non-point sources into Lake Champlain and other waterbodies in Vermont. In this study, we use Bayesian belief network (BBN) to analyze a 2015 survey dataset about adoption of six types of green infrastructures (GSIs) in Vermont’s residential areas. Learning BBNs from physical probabilities of the variables provides a visually explicit approach to reveal the message delivered by the dataset. Using both unsupervised and supervised machine learning algorithms, we are able to generate networks that connect the variables of interest and …


Spectroscopic Insight Into Oxidative Heme Cleavage By The Non-Canonical Heme Oxygenase Isdg From Staphylococcus Aureus, Matthew A. Conger Jan 2018

Spectroscopic Insight Into Oxidative Heme Cleavage By The Non-Canonical Heme Oxygenase Isdg From Staphylococcus Aureus, Matthew A. Conger

Graduate College Dissertations and Theses

IsdG and IsdI are non-canonical heme oxygenases (HO) from Staphylococcus aureus that catalyze the oxidative cleavage of heme to give novel organic products (staphylobilins) and iron as a nutrient for the pathogen. Comparison of the reported equilibrium dissociation constant (Kd) values for heme from IsdG and IsdI compared to the reported concentration of the labile heme pool called into question whether these enzymes are competent HOs in vivo. We took advantage of a second-sphere Trp whose fluorescence is quenched upon heme binding, which led to Kd values 2-3 orders of magnitude smaller than reported in the literature. Importantly, these Kd …


Application Of Geophysical And Geochronological Methods To Sedimentologic And Stratigraphic Problems In The Lower Cambrian Monkton Formation: Northwestern Vermont, Henry C. Maguire Jan 2018

Application Of Geophysical And Geochronological Methods To Sedimentologic And Stratigraphic Problems In The Lower Cambrian Monkton Formation: Northwestern Vermont, Henry C. Maguire

Graduate College Dissertations and Theses

The Monkton Formation of the western shelf stratigraphic sequence in Vermont (VT) is identified as a Lower Cambrian regressive sandstone unit containing parasequences recording tidal flat progradation. Previous workers identified cycles believed to represent parasequences in a portion of a 1034' deep geothermal well drilled at Champlain College in Burlington, Vermont. For this study, both outcrop and well geophysical surveys were completed to better identify gamma emission curves and relative values for parasequences and select lithologies that are indicators of bathymetry and sea level. After using physical stratigraphic techniques to assemble a composite stratigraphic section for the Monkton Formation, analysis …


Land Use, Power, And Knowledge At The Northern Resource Frontier: Mining, Public Engagement, And Contentious Land Imaginaries In Bristol Bay And The Yukon-Kuskokwim Delta, Jonathan Tollefson Jan 2018

Land Use, Power, And Knowledge At The Northern Resource Frontier: Mining, Public Engagement, And Contentious Land Imaginaries In Bristol Bay And The Yukon-Kuskokwim Delta, Jonathan Tollefson

Graduate College Dissertations and Theses

The Donlin and Pebbles mines are two of the eight industrial-scale hard rock mines currently under the review of Alaska’s Large Mine Permitting program. Both projects promise to deliver profit and employment to their respective regions: Pebble to Bristol Bay in the southwest, and Donlin to the Yukon-Kuskokwim Delta, just north of Pebble. Both projects would also produce exceptional quantities of waste and will require almost-unprecedented infrastructure development, potentially threatening the lives and subsistence livelihoods of the Alaska Native peoples in their respective regions. The Pebble project inspired international protest and led to the emergence of a powerful resistance coalition …