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Evaluating Sub-Lethal Effects Of Orchard-Applied Pyrethroids Using Video-Tracking Software To Quantify Honey Bee Behaviors, Erin M. Ingram, Julie Augustin, Marion D. Ellis, Blair Siegfried 2015 University of Nebraska-Lincoln

Evaluating Sub-Lethal Effects Of Orchard-Applied Pyrethroids Using Video-Tracking Software To Quantify Honey Bee Behaviors, Erin M. Ingram, Julie Augustin, Marion D. Ellis, Blair Siegfried

Faculty Publications: Department of Entomology

Managed honey bee, Apis mellifera L., colonies are contracted to pollinate fruit and nut orchards improving crop quality and yield. Colonies placed in orchards are potentially exposed to pyrethroid insecticides used for broad-spectrum pest control. Pyrethroids have been reported to pose minimal risk to bees due to their low application rates in the field and putative repellent properties. This repellency is believed to alter foraging behavior with the benefit of preventing bees from encountering a lethal dose in the field. However, sub-lethal exposure to pyrethroids may adversely impact bee behavior potentially resulting in social dysfunction or disruption of foraging.

This ...


Three-Dimensional Scaffolds Of Graphene, Carbon Nanotubes And Transition-Metal Oxides For Applications In Electronics, Sensors And Energy Storage, Gilbert N. Mbah 2015 University of Nebraska-Lincoln

Three-Dimensional Scaffolds Of Graphene, Carbon Nanotubes And Transition-Metal Oxides For Applications In Electronics, Sensors And Energy Storage, Gilbert N. Mbah

Student Research Projects, Dissertations, and Theses - Chemistry Department

Electronics, sensors and energy storage devices are the new waves behind economic development, security and communication1. Engineering small sizes of electronic, sensors and energy storage devices is the hurdle limiting efficient, portable and vast applications of Nano-devices for economic, security and communication advancement2. Silicon the major material used in transistors has approached its limit to fabricated Nano-devices3. The discovery of free standing, one atomic layer thick and two-dimensional graphene sheets with high conductivity, inert, high specific surface area, stable and high tensile strength material in 2004 has shown capabilities to replaced silicon in electronics, sensors and energy ...


Linkage Analysis And Compositional Studies Of Β-Glucan From Saccharomyces Cerevisiae And Compositional Studies Of Mannan From Candida Albicans, Clara Arthur 2015 East Tennessee State University

Linkage Analysis And Compositional Studies Of Β-Glucan From Saccharomyces Cerevisiae And Compositional Studies Of Mannan From Candida Albicans, Clara Arthur

Electronic Theses and Dissertations

The efficacy of a novel carbohydrate extraction procedure was investigated with methylation analysis and alditol acetate method by Gas Chromatography-Mass Spectrometry. A published extraction procedure for β-glucans was compared to one developed in house. Both procedures gave a dominant glucose peak in the Gas chromatogram indicative of successful β-glucan isolation. Further linkage studies showed four linkage positions for β-glucans isolated with the published method; terminal, 1,3-linkage, 1,6-linkage and 1,3,6-linkage, while β-glucans isolated using the new method showed six linkage positions; terminal, 1,3-linkage, 1,6-linkage, 1,4-linkage, 1,2,3-linkage and 1,3,6-linkage. Diminishing β-glucan ...


Forensic Significance Of Teal Colored Cashmere And Black Acrylic Fibers, Nicole M. Martin 2015 State University of New York Buffalo State

Forensic Significance Of Teal Colored Cashmere And Black Acrylic Fibers, Nicole M. Martin

Forensic Science Theses

Textile fibers are a valuable type of trace evidence within forensic cases. They have the ability to connect a perpetrator to a victim and or a crime scene. Some types of fibers are more prevalent than others. The purpose of this research was to conduct a target fiber study in order to determine the significance of the selected fibers in a forensic case. Two fibers were selected from two different garments, black acrylic fiber and a teal colored cashmere fiber. Unknown fibers were collected from three local clothing stores and counted. Using light microscopy, all 20,164 fibers were eliminated ...


Methodology Study Of N-Deacetylation Of 4-Acetamido-Perfluoroalkylbenzenesulfonimide, Grace Abban 2015 East Tennessee State University

Methodology Study Of N-Deacetylation Of 4-Acetamido-Perfluoroalkylbenzenesulfonimide, Grace Abban

Electronic Theses and Dissertations

In order to improve the synthetic route for diazonium perfluoroalkyl benzenesulfonylimide (PFSI) zwitterionic monomers, N-deacetylation of the coupling product was proposed to replace the reduction of aromatic amine intermediates. A series of hydrolysis methods, such as acid and base catalyzed refluxing, were explored for the N-deacetylation to obtain the PFSI aromatic amine. Factors such as temperature, concentration of acid/base and the time needed for the reaction to take place were investigated in an attempt to optimize the reaction condition. The basic hydrolysis was preferred since it was expected to carry out the N-deacetylation and debromination in ...


The Intersection Of Nuclear Magnetic Resonance And Quantum Chemistry, Yali Wang 2015 University of Nebraska - Lincoln

The Intersection Of Nuclear Magnetic Resonance And Quantum Chemistry, Yali Wang

Student Research Projects, Dissertations, and Theses - Chemistry Department

Nuclear Magnetic resonance and quantum chemistry have been recognized to be strong tools for probing the structure and dynamics of molecules to further solve chemistry and biological problems. Chemical shift measured by NMR experiment and chemical shielding, molecular energy and molecular structure calculated by quantum chemistry provide extensive information.

Exact analytic gradients, are obtained for cavitation, dispersion and repulsion energies and time-dependent density functional theory for the continuum solvation model, which could be used to probe the structure, dynamics and properties of molecules. Copper in CuA azurin is recognized to be coordinated by a structure water molecule by comparing ...


Synthesis Of Phenothiazinium Derivatives, Selorm J. Fanah 2015 East Tennessee State University

Synthesis Of Phenothiazinium Derivatives, Selorm J. Fanah

Electronic Theses and Dissertations

Photodynamic therapy (PDT) employs photosensitizing drugs for treating cancer. Once introduced into the body and localized in tumor cells, these photosensitizers are irradiated with light to produce active singlet oxygen radicals which kill cancer cells. The current drugs used in PDT have low quantum yield and always require a high energy radiation (normally laser). There is always a need for more effective drugs that have a high quantum yield and can be activated by visible light, in order to eliminate side effects caused by laser radiations.

In this work we synthesized derivatives of phenothiazine and phenothiazinium chromophores from the commercially ...


Green Lakes Water Column Parameters: September 2002, Mark A. Teece 2015 SUNY College of Environmental Science and Forestry

Green Lakes Water Column Parameters: September 2002, Mark A. Teece

Green Lakes

No abstract provided.


Hydrogen Exchange Mass Spectrometry For Studying Protein-Ligand Interactions, Modupeola A. Sowole 2015 The University of Western Ontario

Hydrogen Exchange Mass Spectrometry For Studying Protein-Ligand Interactions, Modupeola A. Sowole

Electronic Thesis and Dissertation Repository

Hydrogen deuterium exchange (HDX) coupled with mass spectrometry is widely used for probing protein structure and dynamics. Protein-ligand interactions usually induce a reduction in the measured HDX rates an effect that may be ascribed to stabilization of the protein structure. This work aims to improve the general understanding of the changes in HDX patterns associated with ligand binding.

We initially applied HDX for studying differences between oxy-hemoglobin (Oxy-Hb) and aquomet-hemoglobin (Chapter 2). The results show that the α and β subunits respond differently to the oxy to aquomet transition with the heme binding pocket being destabilized in both cases. The ...


Cover, 2015 University of Tennessee, Knoxville

Cover

International Journal of Nuclear Security

No abstract provided.


Masthead, 2015 University of Tennessee, Knoxville

Masthead

International Journal of Nuclear Security

No abstract provided.


From The Editor, 2015 University of Tennessee, Knoxville

From The Editor

International Journal of Nuclear Security

No abstract provided.


Radiation Damage As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall 2015 United States Military Academy

Radiation Damage As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall

International Journal of Nuclear Security

The ability to determine the time since the forming of seized nuclear material would provide crucial data to be used in its investigation. This paper examines the effects of radiolytic damage caused by the decay of uranium isotopes and assesses the potential forensic utility of examination of these damage regions for determining the time since forming of a metal sample. This paper draws parallels from studies of fission track dating in mineral samples under geologic time and proposes modifications to previously published work in the field of α-recoil track dating in order to determine the time since a metal sample ...


Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall 2015 United States Military Academy

Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall

International Journal of Nuclear Security

The ability to determine the time since forming of seized nuclear material would provide crucial data to be used in its investigation. The time dependent processes of diffusion relevant to this need are examined; to include grain boundary diffusion, and discontinuous precipitation, and an assessment is performed of the utility of examination of impurity and alloying element concentration profiles for use as a pre-detonation nuclear forensics tool for determining the age of a metal sample. Several examples illustrate the effects of time on both binary alloys and multi-component systems. Parallels are drawn from studies of diffusion in mineral samples under ...


Student Writing Competition, 2015 University of Tennessee, Knoxville

Student Writing Competition

International Journal of Nuclear Security

No abstract provided.


From Solution Into The Gas Phase: Studying Protein Hydrogen Exchange And Electrospray Ionization Using Molecular Dynamics Simulation, Robert G. McAllister 2015 The University of Western Ontario

From Solution Into The Gas Phase: Studying Protein Hydrogen Exchange And Electrospray Ionization Using Molecular Dynamics Simulation, Robert G. Mcallister

Electronic Thesis and Dissertation Repository

Here, we apply Molecular Dynamics (MD) simulations to investigate fundamental aspects of structural mass spectrometry (MS). We first examine microscopic phenomena underlying Hydrogen/Deuterium exchange (HDX). HDX interrogates structural dynamics of proteins by measuring the rate of Deuterium uptake into backbone amides. We perform microsecond MD simulations on ubiquitin to investigate this process. We find that HDX protection often cannot be explained by H‑bonding or solvent accessibility considerations. These findings caution against non-critical use of HDX data in structural contexts. We next use MD to examine the Electrospray ionization (ESI) mechanism of proteins. ESI is a soft ionization technique ...


Why Are The Nitro And Sulfone Groups Poor Hydrogen Bonders?, Charles A. Kingsbury 2015 University of Nebraska-Lincoln

Why Are The Nitro And Sulfone Groups Poor Hydrogen Bonders?, Charles A. Kingsbury

Faculty Publications -- Chemistry Department

The interactions of water or methanol with nitromethane and dimethyl sulfone vs. comparison molecules, e.g. dimethylsulfoxide (DMSO), are reported. For nitromethane with water, the classical (edgewise) hydrogen bonded configuration is modestly stabilizing. However, the approach of water over the face of the nitro group is preferred in AM1 calculations. Generally, molecules such as sulfones and nitro compounds have lower energy bonding orbitals than sulfoxides. The energy of the n δ σ* interaction (e.g. nitro lone pair to O-H of water) thus is larger for the nitro and sulfone cases, and this interaction is less prevalent than other cases ...


A Ph Switchable Responsive Surface For The Trapping And Release Of A Hydrophobic Substance, Ali Esmail Karim 2015 Western Kentucky University

A Ph Switchable Responsive Surface For The Trapping And Release Of A Hydrophobic Substance, Ali Esmail Karim

Masters Theses & Specialist Projects

Solid phase extraction is one of the most widely used techniques to trap and release compounds in a solution. A hydrophobic substance will stick efficiently to a hydrophobic surface (the “like dissolves like” principle). With an introduced response (i.e. pH change), a responsive surface can change from hydrophobic to hydrophilic, weakening the hydrophobic substance’s attraction and thus facilitate in an easy removal. A surface has been prepared having a terminal anthranilic acid (AA) moiety on silica gel particles, microscope slides, and TLC plates in three steps. First, a vinyl group was attached to the surface. Then, this vinyl ...


Using Ion Mobility Spectrometry To Study Protein Conformations In The Gas Phase, Yu Sun 2015 The University of Western Ontario

Using Ion Mobility Spectrometry To Study Protein Conformations In The Gas Phase, Yu Sun

University of Western Ontario - Electronic Thesis and Dissertation Repository

The question whether electrosprayed protein ions retain solution-like conformations remains a matter of debate. One way to address this issue involves comparisons of collision cross sections measured by travelling wave ion mobility spectrometry (TWIMS) with the values calculated for model structures. It is often implied that nanoESI is more conducive for the retention of solution structure than regular ESI. Focusing on four different proteins we demonstrated that collision cross section values and collisional unfolding profiles are virtually indistinguishable under both conditions. Calibration can be challenging because differences in the extent of collisional activation for TWIMS and drift tube calibrant data ...


Building An Undergraduate Cohort In High Altitude Ballooning, Mike Davis 2015 Truman College

Building An Undergraduate Cohort In High Altitude Ballooning, Mike Davis

2015 Academic High Altitude Conference

City Colleges of Chicago (CCC), in partnership with DePaul University and the Illinois Space Grant Consortium, has recently been awarded a grant from NASA to develop a research and education program in high-altitude ballooning. The project builds on the Chicago Initiative for Research and Recruitment in the Undergraduate Sciences (CIRRUS) model of undergraduate research and community college/four year college collaborative projects, a successful NSF-funded collaboration between DePaul and CCC. The project has four goals: (1) initiate a year-round undergraduate research program to recruit promising community college students into the STEM disciplines, (2) provide tuition support and fellowships to support ...


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