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Nonlinear Time Dependence Of Dark Current In Charge-Coupled Devices, Justin Charles Dunlap, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

It is generally assumed that charge-coupled device (CCD) imagers produce a linear response of dark current versus exposure time except near saturation. We found a large number of pixels with nonlinear dark current response to exposure time to be present in two scientific CCD imagers. These pixels are found to exhibit distinguishable behavior with other analogous pixels and therefore can be characterized in groupings. Data from two Kodak CCD sensors are presented for exposure times from a few seconds up to two hours. Linear behavior is traditionally taken for granted when carrying out dark current correction and as a result, …

Dark Current In An Active Pixel Complementary Metal-Oxide-Semiconductor Sensor, Justin Charles Dunlap, William Christian Porter, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

We present an analysis of dark current from a complementary metal?oxide?semiconductor (CMOS) active pixels sensor with global shutter. The presence of two sources of dark current, one within the collection area of the pixel and another within the sense node, present complications to correction of the dark current. The two sources are shown to generate unique and characteristic dark current behavior with respect to varying exposure time, temperature, and/or frame rate. In particular, a pixel with storage time in the sense node will show a dark current dependence on frame rate and the appearance of being a ?stuck pixel? with …

Photoelectron Emission Control With Polarized Light In Plasmonic Metal Random Structures, Robert Campbell Word, Joseph Fitzgerald, Rolf Kӧnenkamp

Physics Faculty Publications and Presentations

The authors report on the possibility of switching the emission rate of photoelectrons by polarization changes in the plasmon excitation light. Photoelectron emission is strongly enhanced in the near-field of localized surface plasmons and occurs from areas with typical diameters of 20-70 nm. The underlying physical process involves excitation of a localized surface plasmon polariton with a femtosecond laser pulse, and a subsequent multi-photon photoemission process. The non-linearity of this process leads to a sharp polarization dependence that allows efficient switching of the emission. We demonstrate that a 90° polarization change can result in on/off ratios of ∼100 for electron …

Whose Body Is It Anyway? Human Cells And The Strange Effects Of Property And Intellectual Property Law, Robin Feldman

Faculty Scholarship

No abstract provided.

Advocacy Revalued, Geoffrey C. Hazard, Jr., Dana A. Remus

Faculty Scholarship

No abstract provided.

Floorplan Design And Yield Enhancement Of 3-D Integrated Circuits, Rajeev Kumar Nain

Dissertations and Theses

We have developed a placement-aware 3-D floorplanning algorithm that enables additional wirelength reduction by planning for 3-D placement of logic gates in selected circuit modules during the floorplanning stage. Thus it also bridges the existing gap between 3-D floorplanning and 3-D placement. To reduce the solution space of 3-D floorplanning which is known to be an NP-hard problem, we derive a set of feasibility conditions on the topological representation of a floorplan. In addition, we have designed a fast module packing algorithm that satisfies a set of constraints for placement-aware 3-D floorplanning. Furthermore, we have designed an efficient evolutionary algorithm …

Sounding Rocket Study Of Two Sequential Auroral Poleward Boundary Intensifications, M. R. Mella, Kristina A. Lynch, D. L. Hampton, H. Dahlgren, P. M. Kintner, M. Lessard, D. Lummerzheim, E. T. Lundberg, M. J. Nicolls, H. C. Stenbaek-Nielsen

Dartmouth Scholarship

The Cascades-2 sounding rocket was launched on 20 March 2009 at 11:04:00 UT from the Poker Flat Research Range in Alaska, and flew across a series of poleward boundary intensifications (PBIs). The rocket initially crosses a diffuse arc, then crosses the equatorward extent of one PBI (a streamer), and finally crosses the initiation of a separate PBI before entering the polar cap. Each of the crossings have fundamentally different in situ electron energy and pitch angle structure, and different ground optics images of visible aurora. It is found that the diffuse arc has a quasi-static acceleration mechanism, and the intensification …

A Threat Taxonomy For Mhealth Privacy, David Kotz

Dartmouth Scholarship

Networked mobile devices have great potential to enable individuals (and their physicians) to better monitor their health and to manage medical conditions. In this paper, we examine the privacy-related threats to these so-called \emphmHealth\/ technologies. We develop a taxonomy of the privacy-related threats, and discuss some of the technologies that could support privacy-sensitive mHealth systems. We conclude with a brief summary of research challenges.

Urban Water Demand Modeling: Review Of Concepts, Methods, And Organizing Principles, Heejun Chang, Lily House-Peters

Institute for Sustainable Solutions Publications and Presentations

In this paper, we use a theoretical framework of coupled human and natural systems to review the methodological advances in urban water demand modeling over the past 3 decades. The goal of this review is to quantify the capacity of increasingly complex modeling techniques to account for complex human and natural processes, uncertainty, and resilience across spatial and temporal scales. This review begins with coupled human and natural systems theory and situates urban water demand within this framework. The second section reviews urban water demand literature and summarizes methodological advances in relation to four central themes: (1) interactions within and …

Structuring Expert Input For A Knowledge-Based Approach To Watershed Condition Assessment For The Northwest Forest Plan, Usa, Sean N. Gordon, Kirsten Gallo

Institute for Sustainable Solutions Publications and Presentations

Assessments of watershed condition for aquatic and riparian species often have to rely on expert opinion because of the complexity of establishing statistical relationships among the many factors involved. Such expert-based assessments can be difficult to document and apply consistently over time and space. We describe and reflect on the process of developing a computer-based decision support application from expert judgments for assessing aquatic and riparian conditions over the 100,000 km2 managed by the US federal government under the Northwest Forest Plan. The decision support system helped structure and document the assessment process and provided consistency and transparency to the …

Evaluating Standard Wet Chemistry Techniques And Nir Spectroscopic Models For Determining Composition And Potential Ethanol Yields Of Multi-Species Herbaceous Bioenergy Crops, Ewumbua Menyoli Monona

Agribusiness and Biosystems Engineering

Herbaceous perennials represent a considerable portion of potential biomass feedstocks available for the growing bioenergy industry. Their chemical composition and biomass yields, which are important in determining ethanol potential on an area and mass basis, vary with plant variety and type, environment, and management practices. Therefore, a study was conducted to assess the variability of lignin and carbohydrate content, biomass yields, and theoretical ethanol yields on an area basis among different herbaceous perennial species combinations grown in Minot (2008) and Williston (2008, 2009, and 2010), North Dakota (ND). After wet chemistry compositional analysis was done, the carbohydrate contents were used …

Atomistic Studies Of Shock-Wave And Detonation Phenomena In Energetic Materials, Mikalai Budzevich

USF Tampa Graduate Theses and Dissertations

The major goal of this PhD project is to investigate the fundamental properties of energetic materials, including their atomic and electronic structures, as well as mechanical properties, and relate these to the fundamental mechanisms of shock wave and detonation propagation using state-of-the-art simulation methods. The first part of this PhD project was aimed at the investigation of static properties of energetic materials (EMs) with specific focus on 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). The major goal was to calculate the isotropic and anisotropic equations of state for TATB within a range of compressions not accessible to experiment, and to make predictions of anisotropic sensitivity …

Sources And Pathways To The Environment And Environmental Presence, Tess Chadil

Environmental Science and Management Professional Master's Project Reports

In an attempt to successfully address and reduce contamination from toxic chemicals and other pollutants in the Oregon environment, the Oregon Department of Environmental Quality is in the early stages of developing a comprehensive agency-wide toxics reduction plan. The plan seeks to find a more efficient, sustainable approach to addressing contaminants of concern to human and ecological health. Team Toxics, a work group compromised of members from various DEQ departments, has been created to collaborate and create the framework for developing these strategies. In summer 2009, Team Toxics was in the very early stages of development, and found the need …

The Development Of The Personal Strengths Intervention (Psi) To Improve Self-Determination And Social-Emotional Levels In Postsecondary Students With Learning Disabilities And/Or Adhd: A Multiple Baseline Study, Jennie L. Farmer

USF Tampa Graduate Theses and Dissertations

Students with learning disabilities and/or attention deficit hyperactivity disorder (ADHD) experience decreased academic and social-emotional outcomes when compared to their peers without disabilities. Self-determination, positive psychology, and cognitive theories of learning offer suggestions for improving these outcomes. The purpose of this study was to develop The Personal Strengths Intervention (PSI) and investigate its impact on levels of self-determination and the social-emotional functioning of postsecondary students with learning disabilities and/or ADHD. PSI integrates key elements of self-determination, positive psychology, and cognitive theories. ADHDA multiple baseline design with seven participants was used to examine the intervention effects over time. Results indicate PSI …

A Pilot Study Of Small-Scale Variations In Outdoor Benzene Concentrations, Samantha Catherine Fridh

USF Tampa Graduate Theses and Dissertations

Benzene is an important toxic chemical in urban air and known human carcinogen released substantially by mobile sources. It's important to understand the spatial variation of benzene concentrations in order to understand exposures of susceptible sub-populations such as children and minority groups. Current monitoring networks use large and expensive air samplers that require electricity and restrict the location and number of samplers, not allowing for fine spatial resolution data.

The goals of this study are to develop and evaluate protocols for passive sampling and analysis of ambient benzene concentrations, and conduct a pilot study investigating small-scale variations over an area …

A Reflective Exploration Of A Multiyear Elementary School Learning Community Experience, Susan Jean Ganley

USF Tampa Graduate Theses and Dissertations

This study reports a reflection upon the experience of a multiyear elementary school learning community designed for improved teaching and learning. The exploration uses interview data to describe the perceptions and reflections of the principal and teachers directly engaged in this project of educational reform. The goal of this process is to gain a deeper understanding of the experience and to determine to what factors the participants attribute the outcomes of this project.

Through an auto-ethnographic reflective critical practice inquiry and extended interviews, this study describes the context and environment of this learning community and how the participants reflect on …

Synthesis Of Small Molecule Inhibitors Of Janus Kinase 2, Phosphodiesterase Iv, Gabaa And Nmda Receptors: Investigation Of Mcmurry, Mannich And Chemoenzymatic Strategies, Meghanath Gali

USF Tampa Graduate Theses and Dissertations

Stilbenoids possess a wide range of biological properties such as, anticancer, antiplatelet aggregation, antiestrogenic, antibacterial, antifungal and antiatherogenic, etc. Owing to these therapeutic values, a great deal of attention attracted in the synthesis of derivatives of stilbenes. During the course of the study, G6 a novel stilbenoid was discovered, through high throughput screening, to be a potent inhibitor of mutated JAK2-V617F. The mutated JAK2 variant has been implicated in various myeloproliferative disorders (MPDs) including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) has been targeted by therapeutics. Chapter 2 describes the synthesis of analogs of the stilbenoid G6 …

Electronic Structure Characterization Of Nanocrystalline Surfaces And Interfaces With Photoemission Spectroscopy, Sebastian Gutmann

USF Tampa Graduate Theses and Dissertations

In this study, photoemission spectroscopy (PES) was used to investigate the electronic properties of nanocrystalline titanium dioxide (TiO₂), zinc oxide (ZnO), and cadmium selenide (CdSe). Electrospray deposition technique enabled the preparation of thin films in vacuum from a dispersion prepared outside the vacuum chamber. This method also allowed the step-wise formation of interfaces and the monitoring of the evolution of the electronic structure with intermittent PES characterization.

The work function of nanocrystalline TiO₂ and ZnO was measured with ultraviolet photoemission spectroscopy (UPS) and low-intensity x-ray photoemission spectroscopy (LIXPS). Measurements on environmentally contaminated surfaces revealed an instantaneous and …

Statistical Analysis And Mechanistic Modeling Of Water Quality: Hillsborough Bay, Florida, Keith Hackett

USF Tampa Graduate Theses and Dissertations

Nutrient pollution has been identified as a significant threat to U.S. coastal and estuarine water quality. Though coastal and estuarine waters need nutrients to maintain a healthy, productive ecosystem, excess nutrients can lead to eutrophication. There are significant potential negative consequences associated with eutrophication, including loss of habitat, loss of economic activity, and direct threats to human health. Hillsborough Bay experienced eutrophication in the 1960s and 1970s due to a rapidly growing population and associated increases in nutrient pollution. These eutrophic conditions led to more frequent phytoplankton and macroalgae blooms and declines in seagrasses. To address these problems, a series …

Physical Models Of Amyloid Fibril Assembly, Shannon Elizabeth Hill

USF Tampa Graduate Theses and Dissertations

Formation of large fibers and plaques by amyloid proteins is recognized as the molecular hallmark of an increasing number of human disorders, including Parkinson's disease, Alzheimer's disease and even type II diabetes. The broader objective of my research is to unravel the basic mechanisms that initiate and regulate fibril formation by amyloidogenic proteins. This objective is significant because even basic aspects of how fibril formation proceeds from a soluble, monomeric protein to an insoluble amyloid fibril remain much debated. Furthermore, there is increasingly strong evidence suggesting that intermediates of the aggregation process, with properties distinct from those of mature fibrils, …

Utilizing A Computational Model For The Design Of A Passive Dynamic Walker, Craig Alan Honeycutt

USF Tampa Graduate Theses and Dissertations

Recent interest in using passive dynamic walkers (PDWs) for gait rehabilitation studies has presented a need for a robust, easily built mechanism. Unfortunately, these passive robots are hypersensitive to many variables outside of the usual design considerations that are studied when constructing them. By accentuating previous failures instead of suppressing them, this thesis presents a number of problematic situations commonly experienced when testing and tuning a PDW.

Further, through a complete design of a 4-legged PDW with knees, simple design axioms brought about by myself and others are put into a practical context and applied directly to design. This thesis …

From Source To Sink: An Isotopic Perspective On The Biogeochemical Relationship Between The Everglades And Florida Bay, Ana Maria Hoare

USF Tampa Graduate Theses and Dissertations

Increasing human populations and activities in coastal areas have led to high nutrient loading and estuarine ecosystem decline. Natural hydrological patterns in South Florida have been drastically altered by changes in water management and land use practices. As a result Florida Bay has experienced a series of negative ecosystem effects including hypersalinity events, degradation of water quality, and harmful algal blooms and declines in upper trophic level populations. To remediate ecosystem decline in Florida's coastal ecosystems, the Comprehensive Everglades Restoration Plan proposes to restore a more natural hydrologic flow in the Everglades. It is expected hydrologic restoration efforts will change …

No More Freeways: Urban Land Use-Transportation Dynamics Without Freeway Capacity Expansion, Lei Zhang, We Xu

TREC Final Reports

Observations of the various limitations of freeway capacity expansion have led to a provocative planning and policy question – What if we completely stop building additional freeway capacity. From a theoretical perspective, as a freeway transportation network matures, there exists a saturation point beyond which any additional freeway capacity would only be counterproductive from a welfare point of view, and worsen the existing urban transportation problems. Traditional benefit/cost analysis of individual freeway capacity expansion projects often ignores long-term induced demand and land use changes and does not represent a systems approach to this important theoretical issue. From a practical perspective, …

Personal Knowledge And The Inner Sciences, Martin Zwick

Complex Systems Faculty Publications and Presentations

This paper conceptualizes spiritual disciplines as sciences. It uses this conceptualization to probe into the similarities and differences between modern science and religious tradition, and into the cultural significance and possible future impact of the “new religions”. The paper draws upon the ideas of Michael Polanyi as a possible bridge between science and religion, and proposes that these ideas are relevant not only to the major Western religions, but to Eastern and non-mainstream Western religions as well. Imagining science as a spiritual path, or gnosis, would challenge an exclusivist understanding of scientific knowledge, and suggest the relevance of such knowledge …

System Dynamics Modeling As A Potentially Useful Tool In Analyzing Mitigation Strategies To Reduce Overdose Deaths Associated With Pharmaceutical Opioid Treatment Of Chronic Pain, Wayne Wakeland, Teresa D. Schmidt, Aaron Gilson, J. David Haddox, Lynn Webster

Complex Systems Faculty Publications and Presentations

Objective. To illustrate a system-level, simulationbased approach for evaluating mitigation strategies to address the dramatic rise in abuse, addiction, and overdose deaths associated with the use of pharmaceutical opioid analgesics to treat chronic pain.

Simulated Interventions. Making available drug formulations with increased tamper-resistance, prescriber education programs, and programs that reduce rates of medical user-related abuse and addiction.

Simulated Outcome Measure. Number of overdose deaths of medical users of pharmaceutical opioid analgesics, including those who abuse or have become addicted.

Methods. A demonstration system dynamics model is developed, tested, and used to evaluate the impact of candidate mitigation strategies on the …

Seasonal Ice Mass-Balance Buoys: Adapting Tools To The Changing Arctic, Chris Polashenski, Don Perovich, Jackie Richter-Menge, Bruce Elder

Dartmouth Scholarship

Monitoring the local mass balance of Arctic sea ice provides opportunities to attribute the observed changes in a particular floe’s mass balance to specific forcing phenomena. A shift from multi- year to seasonal ice in large portions of the Arctic presents a challenge for the existing Lagrangian array of autonomous ice mass-balance buoys, which were designed with a perennial ice cover in mind. This work identifies the anticipated challenges of operation in seasonal ice and presents a new autonomous buoy designed to monitor ice mass balance in the seasonal ice zone. The new design presented incorporates features which allow the …

Arctic Sea-Ice Melt In 2008 And The Role Of Solar Heating, Donald K. Perovich, Jacqueline A. Richter-Menge, Kathleen F. Jones, Bonnie Light

Dartmouth Scholarship

There has been a marked decline in the summer extent of Arctic sea ice over the past few decades. Data from autonomous ice mass-balance buoys can enhance our understanding of this decline. These buoys monitor changes in snow deposition and ablation, ice growth, and ice surface and bottom melt. Results from the summer of 2008 showed considerable large-scale spatial variability in the amount of surface and bottom melt. Small amounts of melting were observed north of Greenland, while melting in the southern Beaufort Sea was quite large. Comparison of net solar heat input to the ice and heat required for …

Informal Karst Education In The United States And Internationally, Leslie A. North

USF Tampa Graduate Theses and Dissertations

Despite the abundance of karst terrains and the important role they play in a wide variety of roles including supplying freshwater drinking supplies, no single, comprehensive study investigates the role of informal education for the improved understanding and protection of the terrains. Commonly overlooked anthropogenic karst disturbances partially occur because of the poor dissemination of scientific information to the general populace and policymakers and budgetary and time constraints of municipalities, thus generating a need to use informal education to fill these shortcomings. The purpose of this study was to: 1) establish the status of and quantify the amount of karst-related …

Synthesis And Antimicrobial Activities Of S,S'-Heterosubstituted Disulfides, Praveen Ramaraju

USF Tampa Graduate Theses and Dissertations

Antibiotic resistance is a particularly critical health concern and has increased dramatically over the past two decades. For over a decade the Turos laboratory has been designing small molecules to target pathogenic microbes such as Staphylococcus aureus and the resistant variants like methicillin-resistant Staphylococcus aureus (MRSA). Previously, N-thiolated Β-lactams, N-thiolated 2-oxazolidinones and aromatic disulfides that were synthesized in Dr. Turos' lab have shown strong activity against these bacteria. The present work describes the synthesis and antimicrobial activities of a related structural class called S,S'-heterosubstituted disulfides. For ages, sulfur (elemental) has been used as an antibacterial for controlling infestation and bacterial …

Guiding Electric Fields For Electroporation Applications, Jose Rey

USF Tampa Graduate Theses and Dissertations

Electroporation is the critical step in an electric field mediated drug or gene delivery protocol. Electroporation based protocols have been successfully demonstrated in cancer clinical trials, however, its impact in other applications is still under investigation. A significant roadblock to long term functioning of implantable biosensors in vivo is the tissue reaction in the form of fibrous encapsulation that results in reduced transport to the sensing element of the biosensor. In vivo gene electroporation has a great potential as a means to modify the transport properties of tissues in the proximity of the sensing element of implantable biosensors.

This dissertation …