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Articles 16201 - 16230 of 19479
Full-Text Articles in Entire DC Network
Anticancer Activity And Biophysical Reactivity Of Copper Complexes Of 2-(Benzo[D][1,3]Dioxol-5-Ylmethylene)-N-Alkylhydrazinecarbothioamides, Floyd A. Beckford, Jeffrey Thessing, Alyssa Stott, Alvin A. Holder, Oleg G. Poluektov, Liya Li, Navindra P. Seeram
Anticancer Activity And Biophysical Reactivity Of Copper Complexes Of 2-(Benzo[D][1,3]Dioxol-5-Ylmethylene)-N-Alkylhydrazinecarbothioamides, Floyd A. Beckford, Jeffrey Thessing, Alyssa Stott, Alvin A. Holder, Oleg G. Poluektov, Liya Li, Navindra P. Seeram
Faculty Publications
A series of copper complexes were synthesized from benzo[d][1,3]dioxole-5-carbaldehyde (piperonal) thiosemicarbazones (RHpTSC where R = H, CH3, C2H5 or C6H5 (Ph)). The complexes show interesting variations in geometry depending on the thiosemicarbazone; a dinuclear complex [Cu(HpTSC)Cl]2, a mononuclear complex [Cu(RHpTSC)2Cl2] (R = CH3 or C2H5) and another mononuclear complex [Cu(PhHpTSC)(PhpTSC)Cl] was generated. The complexes bind in a moderately strong fashion to DNA with binding constants on the order of 104 M− 1. They are also strong binders of human serum albumin with binding constants near 104 M− 1. The complexes show good in vitro …
Report And Reflections From Year One Of The Nsf Gk- 12 Program At Usm, Sherry S. Herron, J. Hanna, K. Wingo
Report And Reflections From Year One Of The Nsf Gk- 12 Program At Usm, Sherry S. Herron, J. Hanna, K. Wingo
Faculty Publications
No abstract provided.
Quantifying Cell-To-Cell Variations In Lithium Ion Batteries, Shriram Santhanagopalan, Ralph E. White
Quantifying Cell-To-Cell Variations In Lithium Ion Batteries, Shriram Santhanagopalan, Ralph E. White
Faculty Publications
Lithium ion batteries have conventionally been manufactured in small capacities but large volumes for consumer electronics applications. More recently, the industry has seen a surge in the individual cell capacities, as well as the number of cells used to build modules and packs. Reducing cell-to-cell and lot-to-lot variations has been identified as one of the major means to reduce the rejection rate when building the packs as well as to improve pack durability. The tight quality control measures have been passed on from the pack manufactures to the companies building the individual cells and in turn to the components. This …
Coming Out Of The Dungeon: Mathematics And Role-Playing Games, Kris H. Green
Coming Out Of The Dungeon: Mathematics And Role-Playing Games, Kris H. Green
Mathematical and Computing Sciences Faculty/Staff Publications
After hiding it for many years, I have a confession to make.
Throughout middle school and high school my friends and I would gather almost every weekend, spending hours using numbers, probability, and optimization to build models that we could use to simulate almost anything.
That’s right. My big secret is simple. I was a high school mathematical modeler.
Of course, our weekend mathematical models didn’t bear any direct relationship to the models we explored in our mathematics and science classes. You would probably not even recognize our regular gatherings as mathematical exercises. If you looked into the room, you’d …
Science, C. Mackenzie Brown
A Detailed Record Of Shallow Hydrothermal Fluid Flow In The Sierra Nevada Magmatic Arc From Low-Δ18o Skarn Garnets, M. E. D'Errico, J. S. Lackey, Benjamin E. Surpless, S. L. Loewy, J. L. Wooden, J. D. Barnes, A. Strickland, J. W. Valley
A Detailed Record Of Shallow Hydrothermal Fluid Flow In The Sierra Nevada Magmatic Arc From Low-Δ18o Skarn Garnets, M. E. D'Errico, J. S. Lackey, Benjamin E. Surpless, S. L. Loewy, J. L. Wooden, J. D. Barnes, A. Strickland, J. W. Valley
Earth and Environmental Geosciences Faculty Research
Garnet from skarns exposed at Empire Mountain, Sierra Nevada (California, United States) batholith, have variable δ18O values including the lowest known δ18O values of skarn garnet (–4.0‰) in North America. Such values indicate that surface-derived meteoric water was a significant component of the fluid budget of the skarn-forming hydrothermal system, which developed in response to shallow emplacement (∼3.3 km) of the 109 Ma quartz diorite of Empire Mountain. Values of δ18O, measured in situ across single garnet crystals by secondary ion mass spectrometry, vary considerably (up to 7‰) and sometimes abruptly, indicating variable mixing …
Holocene Earthquakes And Late Pleistocene Slip Rate Estimates On The Wassuk Range Fault Zone, Nevada, Usa, J. M. Bormann, Benjamin E. Surpless, M. W. Caffee, S. G. Wesnousky
Holocene Earthquakes And Late Pleistocene Slip Rate Estimates On The Wassuk Range Fault Zone, Nevada, Usa, J. M. Bormann, Benjamin E. Surpless, M. W. Caffee, S. G. Wesnousky
Earth and Environmental Geosciences Faculty Research
The Wassuk Range fault zone is an 80‐km‐long, east‐dipping, high‐angle normal fault that flanks the eastern margin of the Wassuk Range in central Nevada. Observations from two alluvial fan systems truncated by the fault yield information on the vertical slip rate and Holocene earthquake history along the range front. At the apex of the Rose Creek alluvial fan, radiocarbon dating of offset stratigraphy exposed in two fault trenches shows that multiple earthquakes resulted in 7.0 m of vertical offset along the fault since ∼9400 cal B.P. These data yield a Holocene vertical slip rate of 0.7±0.1 mm/yr. The south trench …
A New Simulation-Based Conflict Indicator As A Surrogate Measure Of Safety, Chen Wang
A New Simulation-Based Conflict Indicator As A Surrogate Measure Of Safety, Chen Wang
Theses and Dissertations--Civil Engineering
Traffic safety is one of the most essential aspects of transportation engineering. However, most crash prediction models are statistically-based prediction methods, which require significant efforts in crash data collection and may not be applied in particular traffic environments due to the limitation of data sources. Traditional traffic conflict studies are mostly field-based studies depending on manual counting, which is also labor-intensive and oftentimes inaccurate. Nowadays, simulation tools are widely utilized in traffic conflict studies. However, there is not a surrogate indicator that is widely accepted in conflict studies.
The primary objective of this research is to develop such a reliable …
Noninvasive Assessment And Modeling Of Diabetic Cardiovascular Autonomic Neuropathy, Siqi Wang
Noninvasive Assessment And Modeling Of Diabetic Cardiovascular Autonomic Neuropathy, Siqi Wang
Theses and Dissertations--Biomedical Engineering
Noninvasive assessment of diabetic cardiovascular autonomic neuropathy (AN): Cardiac and vascular dysfunctions resulting from AN are complications of diabetes, often undiagnosed. Our objectives were to: 1) determine sympathetic and parasympathetic components of compromised blood pressure regulation in patients with polyneuropathy, and 2) rank noninvasive indexes for their sensitivity in diagnosing AN. Continuous 12-lead electrocardiography (ECG), blood pressure (BP), respiration, regional blood flow and bio-impedance were recorded from 12 able-bodied subjects (AB), 7 diabetics without (D0), 7 with possible (D1) and 8 with definite polyneuropathy (D2), during 10 minutes supine control, 30 minutes 70-degree head-up tilt and 5 minutes supine recovery. …
Minimality And Duality Of Tail-Biting Trellises For Linear Codes, Elizabeth A. Weaver
Minimality And Duality Of Tail-Biting Trellises For Linear Codes, Elizabeth A. Weaver
Theses and Dissertations--Mathematics
Codes can be represented by edge-labeled directed graphs called trellises, which are used in decoding with the Viterbi algorithm. We will first examine the well-known product construction for trellises and present an algorithm for recovering the factors of a given trellis. To maximize efficiency, trellises that are minimal in a certain sense are desired. It was shown by Koetter and Vardy that one can produce all minimal tail-biting trellises for a code by looking at a special set of generators for a code. These generators along with a set of spans comprise what is called a characteristic pair, and we …
Hilbert Polynomials And Strongly Stable Ideals, Dennis Moore
Hilbert Polynomials And Strongly Stable Ideals, Dennis Moore
Theses and Dissertations--Mathematics
Strongly stable ideals are important in algebraic geometry, commutative algebra, and combinatorics. Prompted, for example, by combinatorial approaches for studying Hilbert schemes and the existence of maximal total Betti numbers among saturated ideals with a given Hilbert polynomial, three algorithms are presented. Each of these algorithms produces all strongly stable ideals with some prescribed property: the saturated strongly stable ideals with a given Hilbert polynomial, the almost lexsegment ideals with a given Hilbert polynomial, and the saturated strongly stable ideals with a given Hilbert function. Bounds for the complexity of our algorithms are included. Also included are some applications for …
Analytic And Topological Combinatorics Of Partition Posets And Permutations, Jiyoon Jung
Analytic And Topological Combinatorics Of Partition Posets And Permutations, Jiyoon Jung
Theses and Dissertations--Mathematics
In this dissertation we first study partition posets and their topology. For each composition c we show that the order complex of the poset of pointed set partitions is a wedge of spheres of the same dimension with the multiplicity given by the number of permutations with descent composition c. Furthermore, the action of the symmetric group on the top homology is isomorphic to the Specht module of a border strip associated to the composition. We also study the filter of pointed set partitions generated by knapsack integer partitions. In the second half of this dissertation we study descent …
The Hydrodynamic Flow Of Nematic Liquid Crystals In R3, Jay Lawrence Hineman
The Hydrodynamic Flow Of Nematic Liquid Crystals In R3, Jay Lawrence Hineman
Theses and Dissertations--Mathematics
This manuscript demonstrates the well-posedness (existence, uniqueness, and regularity of solutions) of the Cauchy problem for simplified equations of nematic liquid crystal hydrodynamic flow in three dimensions for initial data that is uniformly locally L3(R3) integrable (L3U(R3)). The equations examined are a simplified version of the equations derived by Ericksen and Leslie. Background on the continuum theory of nematic liquid crystals and their flow is provided as are explanations of the related mathematical literature for nematic liquid crystals and the Navier–Stokes equations.
Integrated Geophysical Investigation Of Karst Features – Inner Bluegrass Region Of Kentucky, Jamin C. Frommel
Integrated Geophysical Investigation Of Karst Features – Inner Bluegrass Region Of Kentucky, Jamin C. Frommel
Theses and Dissertations--Earth and Environmental Sciences
High-resolution electrical-resistivity, seismic-refraction, and seismic-reflection surveys were performed at three locations in the Inner Bluegrass Region of Kentucky along coincident survey lines in order to correlate results and determine which method is most effective at locating karst features in this area. The first two survey locations at Slack’s Cave and the Kentucky Horse Park were chosen in order to investigate known karst features. High and low electrical-resistivity anomalies were correlated to air- and water-filled karst voids, respectively. Seismic velocity anomalies, including parabolic time suppressions, amplitude terminations, and surface-wave backscatters, were also observed and correlated to these karst voids. These findings …
The Evolution Of Grenville Basement In The Eastern Great Smoky Mountains; Constraints From U-Pb Zircon Geochronology, Whole Rock Sm-Nd, And Feldspar Pb Geochemistry, Ryan Joel Quinn
Theses and Dissertations--Earth and Environmental Sciences
Identifying the crustal affinity of Grenville basement rocks in the Dellwood quadrangle, western NC, provides insight into the tectonic evolution of eastern Laurentia during Grenville orogenesis. U-Pb zircon geochronology of orthogneiss, augen gneiss, and mafic xenoliths in orthogneiss reveal magmatic pulses at 1130, 1180, and 1330 Ma and metamorphic episodes at 450 and 1040 Ma. Xenoliths in 1330 Ma orthogneiss are as old as 1382 Ma and represent the oldest component of Blue Ridge basement identified to-date. Feldspar Pb isotope values span a range between juvenile-Laurentian and southern-central Appalachian basement/Amazonia. Most Pb isotope data define an array consistent with crustal …
Geology Of The Eau Claire Formation And Conasauga Group In Part Of Kentucky And Analysis Of Their Suitability As Caprocks For Deeper Co2 Sequestration, Ralph E. Bandy Iii
Geology Of The Eau Claire Formation And Conasauga Group In Part Of Kentucky And Analysis Of Their Suitability As Caprocks For Deeper Co2 Sequestration, Ralph E. Bandy Iii
Theses and Dissertations--Earth and Environmental Sciences
Carbon sequestration, or carbon capture and storage (CCS), is the process of capturing anthropogenically generated CO2, transporting the CO2 to an injection site, and then injecting the CO2 into suitable reservoirs for long-term storage, or sequestration. Integral to the successful sequestration of CO2 is an understanding of the confining intervals (seals) above potential reservoirs. The purpose of this thesis research was to perform a detailed geological study of the Eau Claire Formation and equivalent parts of the Conasauga Group in part of the Ohio River Valley region in order to better evaluate its suitability as …
Ultrasonic Concentration Of Microorganisms, Samuel J. Mullins
Ultrasonic Concentration Of Microorganisms, Samuel J. Mullins
Theses and Dissertations--Biosystems and Agricultural Engineering
Concentration of microorganisms from a sample volume would increase the limits of detection of samples used for rapid-detection methods. Rapid detection methods are is advantageous for the food industry to rapidly test for bacteria in order release products on a timely basis. Ultrasonic concentration was considered a promising method for manipulation of microorganisms. An ultrasonic chamber consisting of parallel piezoceramic discs with a reticulated polyurethane foam mesh was used to concentrate Saccharomyces cerevisiae yeast and Escherichia coli bacteria. The concentration of yeast was seen to increase by 200% (from 8.0 x 104 cells mL-1 to 2.4 x 10 …
Evaluation Of Separation Method Additives For The Recovery Of Bacteria From Food Matrices, Jennifer Leanne Frederick
Evaluation Of Separation Method Additives For The Recovery Of Bacteria From Food Matrices, Jennifer Leanne Frederick
Theses and Dissertations--Biosystems and Agricultural Engineering
The microbiological testing of foods is a well-established science. Due to the severity of foodborne pathogen illnesses, the widespread use and implementation of rapid detection methods in food testing labs is increasingly important. The first step for successful testing is sampling. Surfactants have been highly used in food microbiology, but there is not much, if any, published research about the use of fatty alcohols and chemical dispersants as aids in microbial separation. The microbial extraction efficiency of Escherichia coli K12 and Listeria innocua from hot dogs, spinach, and milk was measured using chemical additives (surfactants, fatty alcohols, and a chemical …
Computational Tools For Improving Route Planning In Agricultural Field Operations, Rodrigo S. Zandonadi
Computational Tools For Improving Route Planning In Agricultural Field Operations, Rodrigo S. Zandonadi
Theses and Dissertations--Biosystems and Agricultural Engineering
In farming operation, machinery represents a major cost; therefore, good fleet management can have a great impact on the producer’s profit, especially considering the increasing costs of fuel and production inputs in recent years. One of the tasks to be accomplished in order to improve fleet management is planning the path that the machine should take to cover the field while working. Information such as distance traveled, time and fuel consumption as well as agricultural inputs wasted due to off-target-application areas are crucial in the path planning process. Parameters such as field boundary size and geometry, machine total width as …
Blast-Induced Brain Injury: Influence Of Shockwave Components, Dexter V. Reneer
Blast-Induced Brain Injury: Influence Of Shockwave Components, Dexter V. Reneer
Theses and Dissertations--Neuroscience
Blast-induced traumatic brain injury (bTBI) has been described as the defining injury of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF). Previously, most blast injury research has focused on the effects of blast on internal, gas filled organs due to their increased susceptibility. However, due to a change in enemy tactics combined with better armor and front-line medical care, bTBI has become one of the most common injuries due to blast. Though there has been a significant amount of research characterizing the brain injury produced by blast, a sound understanding of the contribution of each component of the shockwave to the …
Analysis Of Binary Data Via Spatial-Temporal Autologistic Regression Models, Zilong Wang
Analysis Of Binary Data Via Spatial-Temporal Autologistic Regression Models, Zilong Wang
Theses and Dissertations--Statistics
Spatial-temporal autologistic models are useful models for binary data that are measured repeatedly over time on a spatial lattice. They can account for effects of potential covariates and spatial-temporal statistical dependence among the data. However, the traditional parametrization of spatial-temporal autologistic model presents difficulties in interpreting model parameters across varying levels of statistical dependence, where its non-negative autocovariates could bias the realizations toward 1. In order to achieve interpretable parameters, a centered spatial-temporal autologistic regression model has been developed. Two efficient statistical inference approaches, expectation-maximization pseudo-likelihood approach (EMPL) and Monte Carlo expectation-maximization likelihood approach (MCEML), have been proposed. Also, Bayesian …
A Systematic Study Of Transport, Magnetic And Thermal Properties Of Layered Iridates, Oleksandr B. Korneta
A Systematic Study Of Transport, Magnetic And Thermal Properties Of Layered Iridates, Oleksandr B. Korneta
Theses and Dissertations--Physics and Astronomy
A unique feature of the 5d-iridates is that the spin-orbit interaction (SOI) and Coulomb interactions U are of comparable strength and therefore compete vigorously. The relative strength of these interactions stabilizes new exotic ground states that provide a fertile ground for studying new physics. SOI is proportional to Z^4 (Z is the atomic number), and it is now recognized that strong SOI can drive novel narrow-gap insulating states in heavy transition metal oxides such as iridates. Indeed, strong SOI necessarily introduces strong lattice degrees of freedom that become critical to new physics in the iridates. This dissertation thoroughly examines a …
Evaluating Retention In Medical Care And Its Impact On The Health Outcomes Of Individuals Living With Human Inmmunodeficiency Virus, Timothy N. Crawford
Evaluating Retention In Medical Care And Its Impact On The Health Outcomes Of Individuals Living With Human Inmmunodeficiency Virus, Timothy N. Crawford
Theses and Dissertations--Epidemiology and Biostatistics
In the last few years, engagement in medical care among individuals living with HIV has become a major priority among HIV medical providers and public health researchers. Engagement in medical care is an important concept as it involves the process of linking newly diagnosed individuals into medical care and retaining those individuals in care throughout the course of their infection. Although there have been major advances in the management of HIV, like the advent of Highly Active Antiretroviral Therapy, morbidity and mortality due to HIV cannot be fully reduced if the individual does not optimally retain in care. Retention in …
Multiwall Carbon Nanotube Arrays For Thermal Interface Enhancement, Darrell Keith Etheredge
Multiwall Carbon Nanotube Arrays For Thermal Interface Enhancement, Darrell Keith Etheredge
Theses and Dissertations--Mechanical and Aerospace Engineering
High performance/small package electronics create difficult thermal issues for integrated circuits. Challenges exist at material interfaces due to interfacial contact resistances. Multiwall carbon nanotube (MWCNT) arrays are considered to be excellent candidates for use as thermal interface materials (TIMs) due to outstanding thermal/mechanical properties. In this work, MWCNT array TIMs are analyzed in aluminum and carbon fiber composites via flash diffusivity analysis. The effect of TIM thickness, areal/bulk density, surface cleanliness, and volumetric packing fraction; along with the effect of substrate finish and interfacial contact pressure on thermal performance are analyzed. Trends show the best TIMs possess low thickness, high …
Simulation And Experimental Validation Of Airborne And Structure-Borne Noise Transmission In Hvac Plenums, Srinivasan Ramalingam
Simulation And Experimental Validation Of Airborne And Structure-Borne Noise Transmission In Hvac Plenums, Srinivasan Ramalingam
Theses and Dissertations--Mechanical and Aerospace Engineering
This research demonstrates the usage of numerical acoustics to model sound and vibrational energy propagation in HVAC ducts and plenums. Noise and vibration in HVAC systems propagates along three primary paths that can be classified as airborne direct, airborne indirect and structure-borne. The airborne direct path was simulated using acoustic FEM with special boundary conditions to handle the diffuse acoustic field loading and the baffled termination. The insertion loss for a number of different plenum geometries was compared to published measurement results. Results were in good agreement both below and above the cutoff frequency. Additionally, the airborne indirect path, often …
Cryogenic Machining And Burnishing Of Az31b Magnesium Alloy For Enhanced Surface Integrity And Functional Performance, Zhengwen Pu
Cryogenic Machining And Burnishing Of Az31b Magnesium Alloy For Enhanced Surface Integrity And Functional Performance, Zhengwen Pu
Theses and Dissertations--Mechanical and Aerospace Engineering
Surface integrity of manufactured components has a critical impact on their functional performance. Magnesium alloys are lightweight materials used in the transportation industry and are also emerging as a potential material for biodegradable medical implants. However, the unsatisfactory corrosion performance of Mg alloys limits their application to a great extent. Surface integrity factors, such as grain size, crystallographic orientation and residual stress, have been proved to remarkably influence the functional performance of magnesium alloys, including corrosion resistance, wear resistance and fatigue life.
In this dissertation, the influence of machining conditions, including dry and cryogenic cooling (liquid nitrogen was sprayed to …
Specified Motion And Feedback Control Of Engineering Structures With Distributed Sensors And Actuators, Amirhossien Ghasemi
Specified Motion And Feedback Control Of Engineering Structures With Distributed Sensors And Actuators, Amirhossien Ghasemi
Theses and Dissertations--Mechanical and Aerospace Engineering
This dissertation addresses the control of flexible structures using distributed sensors and actuators. The objective to determine the required distributed actuation inputs such that the desired output is obtained. Two interrelated facets of this problem are considered. First, we develop a dynamic-inversion solution method for determining the distributed actuation inputs, as a function of time, that yield a specified motion. The solution is shown to be useful for intelligent structure design, in particular, for sizing actuators and choosing their placement. Secondly, we develop a new feedback control method, which is based on dynamic inversion. In particular, filtered dynamic inversion combines …
Simulation Of Whistle Noise Using Computational Fluid Dynamics And Acoustic Finite Element Simulation, Jiawei Liu
Simulation Of Whistle Noise Using Computational Fluid Dynamics And Acoustic Finite Element Simulation, Jiawei Liu
Theses and Dissertations--Mechanical and Aerospace Engineering
The prediction of sound generated from fluid flow has always been a difficult subject due to the nonlinearities in the governing equations. However, flow noise can now be simulated with the help of modern computation techniques and super computers. The research presented in this thesis uses the computational fluid dynamics (CFD) and the acoustic finite element method (FEM) in order to simulate the whistle noise caused by vortex shedding. The acoustic results were compared to both analytical solutions and experimental results to better understand the effects of turbulence models, fluid compressibility, and wall boundary meshes on the acoustic frequency response. …
A Filter-Forcing Turbulence Model For Large Eddy Simulation Incorporating The Compressible "Poor Man's" Navier--Stokes Equations, Joshua Strodtbeck
A Filter-Forcing Turbulence Model For Large Eddy Simulation Incorporating The Compressible "Poor Man's" Navier--Stokes Equations, Joshua Strodtbeck
Theses and Dissertations--Mechanical and Aerospace Engineering
A new approach to large-eddy simulation (LES) based on the use of explicit spatial filtering combined with backscatter forcing is presented. The forcing uses a discrete dynamical system (DDS) called the compressible ``poor man's'' Navier--Stokes (CPMNS) equations. This DDS is derived from the governing equations and is shown to exhibit good spectral and dynamical properties for use in a turbulence model. An overview and critique of existing turbulence theory and turbulence models is given. A comprehensive theoretical case is presented arguing that traditional LES equations contain unresolved scales in terms generally thought to be resolved, and that this can only …
A New Metric-Based Lca Method For Assessing The Sustainability Performance Of Metallic Automotive Components, Xiangxue Zhang
A New Metric-Based Lca Method For Assessing The Sustainability Performance Of Metallic Automotive Components, Xiangxue Zhang
Theses and Dissertations--Mechanical and Aerospace Engineering
This thesis presents a new metric-based Life-cycle Assessment (LCA) method for assessing the sustainability performance of metallic automotive components. The unique feature of this research work include the development and use of a metrics-based product sustainability index (ProdSI) methodology by considering the total life-cycle approach and the triple bottom line (TBL) with the 6R methodology. It has been shown that the manufactured product’s sustainability performance can be comprehensively assessed using this new methodology. The major focus of this research is the integration of the 6R activities (Reduce, Reuse, Recycle, Recover, Redesign and Remanufacture). Four life-cycle stages of the …