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The Analysis Of Palaeobotanical Remains From Native American Sites In The Tennessee Region Of The Upper Cumberland Plateau., Chase W. Beck

Electronic Theses and Dissertations

Sediment samples were collected from 3 rock shelter sites and one natural pond on the Upper Cumberland Plateau. Samples were processed to quantitatively and qualitatively evaluate pollen and charcoal abundance as well as other palaeobotanicals. The analysis was to determine when prehistoric Native Americans began controlled burns to enhance resources acquisition. Samples were also analyzed for the presence of pollen to determine vegetation changes that may accompany the use of controlled burns and to determine the onset of horticulture. The Upper Cumberland Plateau is often considered a marginal area used only seasonally by Native Americans; however, management practices may have …

Early Stopping Of A Neural Network Via The Receiver Operating Curve., Daoping Yu

Electronic Theses and Dissertations

This thesis presents the area under the ROC (Receiver Operating Characteristics) curve, or abbreviated AUC, as an alternate measure for evaluating the predictive performance of ANNs (Artificial Neural Networks) classifiers. Conventionally, neural networks are trained to have total error converge to zero which may give rise to over-fitting problems. To ensure that they do not over fit the training data and then fail to generalize well in new data, it appears effective to stop training as early as possible once getting AUC sufficiently large via integrating ROC/AUC analysis into the training process. In order to reduce learning costs involving the …

Narcissism And Binge Drinking: Exploring The Role Of Overconfidence And Confidence-Based Risk-Taking., Alicia M. Wood

Electronic Theses and Dissertations

Binge drinking (BD) entails excessive alcohol intake in a short time period. Despite numerous negative outcomes associated with BD and efforts to curtail it, rates remain steady. Thus, it is important to identify "who" binge drinks and "why" it occurs. Drawing from past research, I sought to replicate the link between trait narcissism and BD; moreover, I examined if overconfidence and confidence-based risk-taking assessed via the Georgia Gambling Task (GGT), explained why they did so. The results generally supported my hypotheses. As expected, narcissism related to poor GGT performance and high levels of BD; likewise, poor GGT performance related to …

Synthesis Of A Water Soluble Resveratrol Derivative As A Potential Anti-Cancer Drug., Augustine Essel

Electronic Theses and Dissertations

Research on development of water soluble anti-cancer drugs is one of the great challenges of modern medicinal chemistry. Resveratrol (Res) is one of the many phytoalexins producing stilbenoids present in several medicinal plants, grape skin, peanuts, and red wine. It has been found to exhibit anti-cancer, anti-inflammatory, and anti-oxidant properties. Water solubility and bioavailability are some of the setbacks of this interesting compound. In view of this, effort has been made to synthesize amino acid derivative of resveratrol to improve its bioavailability and solubility in water. Methyl 4-{-[(1E)-2-(3, 5-dihydroxyphenyl)-ethenyl] - phenoxy} butyrate (7), a novel ester intermediate, has been synthesized …

Isolation Of A Siderophore Produced By Methicillin-Resistant Staphylococcus Aureus Strain H372., Rachel Elizabeth Presswood

Electronic Theses and Dissertations

Iron is necessary for many cellular processes such as the electron transport chain and gene regulation. However, most iron on earth is found in insoluble iron-hydroxide complexes. In addition, iron is tightly sequestered in the human body by proteins such as transferrin, making it unavailable for pathogens. In order to overcome these limitations bacteria have evolved siderophores. Siderophores are low molecular weight compounds that bind ferric iron with a high affinity. Staphylococcus aureus is an important human pathogen that is known to produce at least four siderophores, and these siderophores contribute to its virulence. S. aureus strain H372 was found …

Unescosat: The United Nations’ First Satellite, Donald Platt

Small Satellite Conference

An international effort is underway to produce the first satellite in the history of the United Nations. The idea of the preparation and launch, with the endorsement of the UNESCO branch of the United Nations, of an international satellite to promote science education, public awareness of science, and international co-operation in the basic sciences, was presented by the National Commission of the Russian Federation for UNESCO to the UNESCO basic sciences committee. The General Conference of UNESCO at its 35th session in October 2009 approved an amendment to the UNESCO draft Programme and Budget for 2010-2011 concerning the project. The …

Switchable Antenna Polarization Using Surface-Integrated Fluidic Loading Mechanisms , Sean Goldberger, Frank Drummond, Joel Barrera, Stephen Davis, Jamie Edelen, Michelle Geppert, Yashavaun Judie, Quinn Manley, Cameron Peters, Samantha Smith, Gregory Huff

Small Satellite Conference

Multipath wireless communication can increase system-level demands on antenna radiation behavior, impedance matching, and bandwidth requirements. Research with the Space Engineering Institute at Texas A&M University has developed a novel antenna polarization reconfiguration system using nanoparticle dispersions. Potential applications encompass space and military missions operating in harsh physical and electromagnetic surroundings, multiple input and output (MIMO) systems, and cognitive radios. This paper will discuss the design, fabrication, and reconfigurable performance of a single crossed-dipole microstrip antenna with pressure-driven and electrokinetic manipulation of nanoparticle dispersions. Appropriately positioned gaps, on the crossed dipole, manage the frequency and antenna polarization diversity. Analytical, simulated, …

Potential Biases In Estimating The Rate Parameter Of Sigmoid Growth Functions, Robert Ricklefs, Suzanne Austin, Tara Robinson, W. Robinson

Biology Department Faculty Works

1. We compare biases in estimates of the rate constant of the logistic and Gompertz functions applied to avian growth using three methods of parameter estimation. The methods differ in how the asymptote is determined, and consist of either floating asymptotes estimated from the full data (floating A) or data truncated at 70% of the adult mass (70%A), or fixing the asymptote at the adult mass (fixed A).2. First, using data for two passerine species exhibiting different growth patterns, we truncated mass measurements at different ages to explore how each method of growth rate estimation responded to simulated differences in …

Wyckoff, Associate Professor Of Biology, Receives National Science Foundation Grant To Study Minnesota Forests, University Relations

Campus News Archive

Research focuses on ecosystem change in western Minnesota in the 21st century

Gregg Cross Interview, Wright State University Alumnus, Chris Wydman, Gregg Cross

Wright State University Retirees Association Oral History Project

Chris Wydman interviewed Gregg Cross on August 12, 2010 about the founding of Wright State University and his perspective as a student athlete in the early years of the University. In the interview Mr. Cross discusses his career and his decision to come to Wright State as one of the early students.

Cortisol Exerts Bi-Phasic Regulation Of Inflammation In Humans, Mark P. Yeager, Patricia Pioli, Paul M. Guyre

Dartmouth Scholarship

Natural and synthetic glucocorticoids (GCs) have been used for decades to suppress inflammation. In this paper, we re-examine the role of the endogenous GC, cortisol, as a primary homeostatic regulator of the human inflammatory response to injury. Our data show that cortisol regulation of innate immunity can be both pro-inflammatory and anti-inflammatory. Using a human model of in vivo cortisol depletion, we first show that baseline (diurnal) cortisol concentrations do not exert an anti-inflammatory effect. This is the first clue that cortisol regulation of inflammation is not represented by a linear dose-response relationship. We next show in surgical patients that …

Delayed Onset Of A Daytime Nap Facilitates Retention Of Declarative Memory, Sara E. Alger, Hiuyan Lau, William Fishbein

Publications and Research

Background Learning followed by a period of sleep, even as little as a nap, promotes memory consolidation. It is now generally recognized that sleep facilitates the stabilization of information acquired prior to sleep. However, the temporal nature of the effect of sleep on retention of declarative memory is yet to be understood. We examined the impact of a delayed nap onset on the recognition of neutral pictorial stimuli with an added spatial component. Methodology/Principal Findings Participants completed an initial study session involving 150 neutral pictures of people, places, and objects. Immediately following the picture presentation, participants were asked to make …

Thinking Outside The Curve, Part Ii: Modeling Fetal-Infant Mortality, Richard Charnigo, Lorie W. Chesnut, Tony Lobianco, Russell S. Kirby

Statistics Faculty Publications

BACKGROUND: Greater epidemiologic understanding of the relationships among fetal-infant mortality and its prognostic factors, including birthweight, could have vast public health implications. A key step toward that understanding is a realistic and tractable framework for analyzing birthweight distributions and fetal-infant mortality. The present paper is the second of a two-part series that introduces such a framework.

METHODS: We propose estimating birthweight-specific mortality within each component of a normal mixture model representing a birthweight distribution, the number of components having been determined from the data rather than fixed a priori.

RESULTS: We address a number of methodological issues related to our …

Synthesis And Characterization Of An Oligothiophene-Ruthenium Complex And Synthesis And Optical Properties Of Oligothiophene-Ruthenium Complexes Bound To Cdse Nanoparticles, Nathan A. Bair

Theses and Dissertations

Oligothiophenes are of increasing interest in organic based electronic devices in part due to their high electron and hole mobilities. In an organic photovoltaic (OPV) device, the electronic properties of oligothiophenes make them advantageous as charge transfer junctions. To serve as charge transfer junctions, oligothiophenes must be functionalized to bind to the donor and acceptor parts of the device. The donor and acceptor parts are different materials and the synthesis of asymmetric oligothiophenes is of great interest. Previous researchers in our lab synthesized four asymmetric oligothiophenes, two with two thiophene subunits and two with four. Each set of oligothiophenes contained …

Effects Of A Shallow-Water Hydrothermal Vent Gradient On Benthic Calcifiers, Tutum Bay, Ambitle Island, Papua New Guinea, Brienne E. Engel

USF Tampa Graduate Theses and Dissertations

Ocean acidification is occurring in response to rapidly increasing concentrations of atmospheric CO2. Shallow-water hydrothermal vent systems have been proposed as natural laboratories for studying the effects of elevated pCO2 on benthic communities. Hydrothermal vents occur at depths of approximately 10m in Tutum Bay, Ambitle Island, Papua New Guinea; these vents are surrounded by a typical-appearing fringing coral-reef community. Groups of live specimens of seven species of reef-dwelling, larger benthic foraminifers, along with segments of calcareous green algae broken from live thalli, were collected from a reef location, placed in small mesh bags, and deployed for five days at six …

Passive Magnetic Attitude Control For Cubesat Spacecraft , David Gerhardt

Small Satellite Conference

CubeSats are a growing and increasingly valuable asset specifically to the space sciences community. However, due to their small size CubeSats provide limited mass (< 4 kg) and power (typically < 6W insolated) which must be judiciously allocated between bus and instrumentation. There are a class of science missions that have pointing requirements of 10-20 degrees. Passive Magnetic Attitude Control (PMAC) is a wise choice for such a mission class, as it can be used to align a CubeSat within f10f of the earth's magnetic field at a cost of zero power and < 50g mass. One example is the Colorado Student Space Weather Experiment (CSSWE), a 3U CubeSat for space weather investigation. The design of a PMAC system is presented for a general 3U CubeSat with CSSWE as an example. Design aspects considered include: external torques acting on the craft, magnetic parametric resonance for polar orbits, and the effect of hysteresis rod dimensions on dampening supplied by the rod. Next, the development of a PMAC simulation is discussed, including the equations of motion, a model of the earth's magnetic field, and hysteresis rod response. Key steps of the simulation are outlined in sufficient detail to recreate the simulation. Finally, the simulation is used to verify the PMAC system design, finding that CSSWE settles to within 10f of magnetic field lines after 6.5 days.

Routine Scheduled Space Access For Secondary Payloads , Jason Andrews, Jeff Cannon

Small Satellite Conference

Commercial launch vehicles often launch with primary payloads that do not max-out launch capacity to the destination orbit. To take advantage of this excess capability, secondary payloads can be launched with the primary payload, providing an economical means to get small spacecraft to orbit, as well as providing additional revenue to the launch provider. Up until now, these secondary payload opportunities have been limited and sporadic, with payloads waiting for rides due to mismatched orbit destinations, availability of launch vehicle capacity, and prohibitive cost. With the advent of new U.S. commercial launch services, the opportunities for launch of small secondary …

We Are...Marshall, August 11, 2010, Office Of Marshall University Communications

We Are ... Marshall: the Newsletter for Marshall University 1999-2023

No abstract provided.

The Role Of Morphology In The Locomotor Performance Of Arboreal Snakes, Ronald C. Rozar

Open Access Dissertations

Adaptation is difficult to directly demonstrate. However, the role that a morphological character, or suite of characters plays in the fitness of a species can be elucidated by examining the intermediate link between morphology and fitness â?? performance. Linking morphology to performance, and then performance to fitness can demonstrate the adaptive significance of a morphological character. Arboreal snakes possess a suite of characteristic morphological traits that differentiate these snakes from their terrestrial counterparts, and these characteristic traits have been presumed to be of an adaptive nature. To determine if these characteristic traits are of an adaptive nature I have taken …

Origin Of The Genus Homo, Holly M. Dunsworth

Sociology and Anthropology Faculty Publications

The origin of the genus Homo in Africa signals the beginning of the shift from increasingly bipedal apes to primitive, large-brained, stone tool-making, meat-eaters that traveled far and wide. This early part of the human genus is represented by three species: Homo habilis, Homo rudolfensis, and Homo erectus. H. habilis is known for retaining primitive features that link it to australopiths and for being the first stone tool makers. Little is known about H. rudolfensis except that it had a relatively large brain and large teeth compared to H. habilis and that it overlapped in time and space with other …

The Murray Ledger And Times, August 11, 2010, The Murray Ledger And Times

The Murray Ledger & Times

No abstract provided.

Higher Education In New Mexico - Phase 1 Report: President Schmidly's Remarks, David Schmidly

President Schmidly's Administration

"'I speak for the entire UNM team when I tell you that, from our perspective, the report is excellent. As we say in our formal response, we believe that if most of the recommendations in the Report were implemented, we would have a better performing system of higher education in New Mexico. And the idea of having a true ""system"" is a critical concept as we look to the future. It is this concept, and UNM\'s role in that system, that I would like to spend a significant portion of my time talking about this morning.'"

Rapid Cell Extraction In Aqueous Two-Phase Microdroplet Systems, Kalpana Vijayakumar, Shelly Gulati, Andrew J. De Mello, Joshua B. Edel

All Faculty Articles - School of Engineering and Computer Science

Distinguishing specific cells is an essential technique in cell research and clinical diagnostics. We report a novel method to passively isolate and extract cells in a microfluidic device. We utilise a droplet-based microfluidic system to generate an aqueous two phase system in which aqueous droplets consist of two phases in the form of a double emulsion. Specifically, we generate PEG droplets that completely encapsulate DEX droplets within a microfluidic channel. Target cells can be introduced directly into the droplets and driven to partition to the more favourable phase, whilst still being contained within the aqueous droplet. Human T lymphoma cells, …

Acaricidal Activity Of Eugenol Based Compounds Against Scabies Mites, Cielo Pasay, Kate Mounsey, Graeme Stevenson, Rohan Davis, Larry G. Arlian, Marjorie Morgan, Diann Vyszenski-Moher, Kathy Andrews, James Mccarthy

Biological Sciences Faculty Publications

Background

Human scabies is a debilitating skin disease caused by the “itch mite” Sarcoptes scabiei. Ordinary scabies is commonly treated with topical creams such as permethrin, while crusted scabies is treated with topical creams in combination with oral ivermectin. Recent reports of acaricide tolerance in scabies endemic communities in Northern Australia have prompted efforts to better understand resistance mechanisms and to identify potential new acaricides. In this study, we screened three essential oils and four pure compounds based on eugenol for acaricidal properties.

Methodology/Principal Findings

Computer Aided Contour Profiling Of High Strength Deposits, Sriram Praneeth Isanaka, Amar Bala Sridhar, Frank W. Liou, Joseph William Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Additive manufacturing processes suffer from the effect of ripples, edge rounding and surface variations. To reduce their effect, ideal process parameters for the laser deposition process were investigated. Also, a new method was identified to analyze deposits by accurately plotting their contours. This was achieved through point cloud data of the deposits generated using coordinate measurement and 3D scanning. Curve fitting was performed on the data in Matlab to generate the contours of the deposit. The intercept values, heights, and contact angle of the curves give an indication of the uniformity of deposits and aid in reducing defects.

Freeze Extrusion Fabrication Of 13-93 Bioactive Glass Scaffolds For Bone Repair, Tieshu Huang, Nikhil D. Doiphode, M. N. Rahaman, Ming-Chuan Leu, B. Sonny Bal, D. E. Day

Materials Science and Engineering Faculty Research & Creative Works

There is an increasing demand for synthetic scaffolds with the requisite biocompatibility, internal architecture, and mechanical properties for the bone repair and regeneration. In this work, scaffolds of a silicate bioactive glass (13-93) were prepared by a freeze extrusion fabrication (FEF) method and evaluated in vitro for potential applications in bone repair and regeneration. The process parameters for FEF production of scaffolds with the requisite microstructural characteristics, as well as the mechanical and cell culture response of the scaffolds were evaluated. After binder burnout and sintering (60 min at 700°C), the scaffolds consisted of a dense glass network with interpenetrating …

Selective Laser Sintering Of 13-93 Bioactive Glass, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Bioactive glasses are more promising than biopolymers in fabricating scaffolds for bone tissue repair because they convert to hydroxyapatite, when implanted in vivo. Both direct and indirect selective laser sintering (SLS) methods of 13-93 bioactive glass were considered in this research to study the feasibility of fabricating scaffolds for bone repair applications. Stearic acid was used as the binder in the indirect method to fabricate the scaffolds. The green scaffolds underwent binder burnout and sintering at various soaking conditions between 675⁰C and 700⁰C, achieving a maximum compressive strength of 23.6 MPa, which is higher than that of the human cancellous …

Multi-Axis Planning System (Maps) For Hybrid Laser Metal Deposition Processes, Frank W. Liou, Jianzhong Ruan, Todd E. Sparks

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper summarizes the research and development of a Multi-Axis Planning System (MAPS) for hybrid laser metal deposition processes. The project goal is to enable the current direct metal deposition systems to fully control and utilize multi-axis capability to make complex parts. MAPS allows fully automated process planning for multi-axis layered manufacturing to control direct metal deposition machines for automated fabrication. Such a capability will lead to dramatic reductions in lead time and manufacturing costs for high-value, low-volume components with high performance material. The overall approach, slicing algorithm, machine simulation for planning validation, and the planning results will be presented.

Mirnas In Newt Lens Regeneration: Specific Control Of Proliferation And Evidence For Mirna Networking, Kenta Nakamura, Nobuyasu Maki, Albert Trinh, Heidi W. Trask, Jiang Gui, Craig R. Tomlinson, Panagiotis A. Tsonis

Dartmouth Scholarship

Background:

Lens regeneration in adult newts occurs via transdifferentiation of the pigment epithelial cells (PECs) of the dorsal iris. The same source of cells from the ventral iris is not able to undergo this process. In an attempt to understand this restriction we have studied in the past expression patterns of miRNAs. Among several miRNAs we have found that mir-148 shows an up-regulation in the ventral iris, while members of the let-7 family showed down-regulation in dorsal iris during dedifferentiation.

Methodology/Principal Findings:

Herbivore And Fungal Pathogen Exclusion Aects The Seed Production Of Four Common Grassland Species, Timothy L. Dickson, Charles E. Mitchell

Biology Faculty Publications

Insect herbivores and fungal pathogens can independently affect plant fitness, and may have interactive effects. However, few studies have experimentally quantified the joint effects of insects and fungal pathogens on seed production in non-agricultural populations. We examined the factorial effects of insect herbivore exclusion (via insecticide) and fungal pathogen exclusion (via fungicide) on the population-level seed production of four common graminoid species (Andropogon gerardii, Schizachyrium scoparium, Poa pratensis, and Carex siccata) over two growing seasons in Minnesota, USA. We detected no interactive effects of herbivores and pathogens on seed production. However, the seed production of …