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An Examination Of Youth Voice Via Quasi-Experimental Methodology, Melissa Cater, Krisanna Machtmes, Janet Fox Oct 2008

An Examination Of Youth Voice Via Quasi-Experimental Methodology, Melissa Cater, Krisanna Machtmes, Janet Fox

Journal of Youth Development

The purpose of the study discussed was to determine if youth voice affects the ownership and engagement of youth in a county 4-H program. A youth-led approach was used with the treatment group to facilitate youth and adults sharing decision-making power. The comparison group utilized an adult-centered approach where decisions about the club programming were made strictly by the adults. A pre-and post-measurement design was used. Analysis of covariance was employed to determine if differences existed between youth participating in the treatment group and comparison groups and if differences existed between youth based on race. Findings indicated statistically significant differences …

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The Tiger Vol. 102 Issue 19 2008-10-10, Clemson University Oct 2008

The Tiger Vol. 102 Issue 19 2008-10-10, Clemson University

Tiger Newspapers

No abstract provided.

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Neutrino-Nucleus Reaction Cross Sections For Light Element Systhesis In Supernova Explosions, Takashi Yoshida, Toshio Suzuki, Satoshi Chiba, Toshitaka Kajino, Hidekazu Yokomakura, Keiichi Kimura, Akira Takamura, Dieter H. Hartmann Oct 2008

Neutrino-Nucleus Reaction Cross Sections For Light Element Systhesis In Supernova Explosions, Takashi Yoshida, Toshio Suzuki, Satoshi Chiba, Toshitaka Kajino, Hidekazu Yokomakura, Keiichi Kimura, Akira Takamura, Dieter H. Hartmann

Publications

The neutrino-nucleus reaction cross sections of 4He and 12C are evaluated using new shell model Hamiltoni-ans. Branching ratios of various decay channels are calculated to evaluate the yields of Li, Be, and B producedthrough the ν -process in supernova explosions. The new cross sections enhance the yields of7Li and11B pro-duced during the supernova explosion of a 16.2 M⊙star model compared to the case using the conventionalcross sections by about 10%. On the other hand, the yield of10B decreases by a factor of two. The yieldsof6Li,9Be, and the radioactive nucleus10 Be are found at a level of ∼ 10−11M⊙. The temperature …

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A Photometric Redshift Of Z = 1.8{+0.4}{-0.3} For The Agile Grb 080514b, A. Rossi, A. De Ugarte Postigo, P. Ferrero, D. A. Kann, S. Klose, S. Schulze, J. Greiner, P. Schady, R. Filgas, E E. Gonsalves, A Küpcü Yoldaş, T Krühler, G Szokoly, A Yoldas, P.M.J. Afonso, C Clemens, J S. Bloom, D A. Perley, J.P.U. Fynbo, A J. Castro-Tirado, J Gorosabel, P Kubanek, A C. Updike, Dieter H. Hartmann, A Giuliani, S T. Holland, L Hanlon, M Bremer, J French, G Melady, D A. Garcia-Hernandez Oct 2008

A Photometric Redshift Of Z = 1.8{+0.4}{-0.3} For The Agile Grb 080514b, A. Rossi, A. De Ugarte Postigo, P. Ferrero, D. A. Kann, S. Klose, S. Schulze, J. Greiner, P. Schady, R. Filgas, E E. Gonsalves, A Küpcü Yoldaş, T Krühler, G Szokoly, A Yoldas, P.M.J. Afonso, C Clemens, J S. Bloom, D A. Perley, J.P.U. Fynbo, A J. Castro-Tirado, J Gorosabel, P Kubanek, A C. Updike, Dieter H. Hartmann, A Giuliani, S T. Holland, L Hanlon, M Bremer, J French, G Melady, D A. Garcia-Hernandez

Publications

The AGILE gamma-ray burst GRB 080514B is the first detected to have emission above 30 MeV and an optical afterglow. However, no spectroscopic redshift for this burst is known. We report on our ground-based optical/NIR and millimeter follow-up observations of this event at several observatories, including the multi-channel imager GROND on La Silla, supplemented by Swift UVOT and Swift XRT data. The spectral energy distribution (SED) of the optical/NIR afterglow is found to decline sharply bluewards to the UV bands, which can be utilized in estimating the redshift. Fitting the SED from the Swift UVOT uvw2bandto the H band, we …

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Erratum: "Warm Hcn, C2h2, And Co In The Disk Of Gv Tau'', E L. Gibb, K A. Vanbrunt, Sean D. Brittain, T W. Rettig Oct 2008

Erratum: "Warm Hcn, C2h2, And Co In The Disk Of Gv Tau'', E L. Gibb, K A. Vanbrunt, Sean D. Brittain, T W. Rettig

Publications

This is an Erratum for the article 2007 ApJ 660 1572

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Cataloging As A Tool For Outreach - Bringing Campus Collections Together, Derek Wilmott Oct 2008

Cataloging As A Tool For Outreach - Bringing Campus Collections Together, Derek Wilmott

Presentations

Clemson University Libraries and Tillman Education Media Center cataloging project.

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The Rapidly Flaring Afterglow Of The Very Bright And Energetic Grb 070125, Adria C. Updike, Josh B. Haislip, Melissa C. Nysewander, Andrew S. Fruchter, D. Alexander Kann, Sylvio Klose, Peter A. Miline, G. Grant Williams, Weikang Zheng, Carl W. Hergenrother Sep 2008

The Rapidly Flaring Afterglow Of The Very Bright And Energetic Grb 070125, Adria C. Updike, Josh B. Haislip, Melissa C. Nysewander, Andrew S. Fruchter, D. Alexander Kann, Sylvio Klose, Peter A. Miline, G. Grant Williams, Weikang Zheng, Carl W. Hergenrother

Publications

We report on multiwavelength observations, ranging from X-ray to radio wave bands, of the IPN-localized gamma-ray burst GRB 070125. Spectroscopic observations reveal the presence of absorption lines due to O i,Si ii,and C iv, implying a likely redshift of z ¼1:547. The well-sampled light curves, in particular from 0.5 to 4 days after the burst, suggest a jet break at 3.7 days, corresponding to a jet opening angle of $7.0, and implying an intrinsic GRB energy in the 1Y10,000 keV band of around E ¼(6:3Y6:9) ; 1051 ergs (based on the fluences measured by the gamma-ray de-tectorsof the IPN).GRB070125 is …

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The Tiger Vol. 102 Issue 15 2008-09-12, Clemson University Sep 2008

The Tiger Vol. 102 Issue 15 2008-09-12, Clemson University

Tiger Newspapers

No abstract provided.

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Modeling Of Space-Charge-Limited Current Injection Incorporating An Advanced Model Of The Poole-Frenkel Effect, Satoshi Takeshita Sep 2008

Modeling Of Space-Charge-Limited Current Injection Incorporating An Advanced Model Of The Poole-Frenkel Effect, Satoshi Takeshita

All Theses

The current flow due to Space-Charge-Limited (SCL) emission is well known and the associated current-voltage power law relationship can be observed in many materials, particularly in insulators and semiconductors. Under an applied field, the space-charge effect occurs due to the carrier injection, and the resulting current due to the presence of the space-charge effect is referred to as SCL current. In the SCL current theory, the presence of localized traps in a material has a significant effect on the transport of injected carriers; however, in the first order SCL model, the trap barrier height is assumed to be constant for …

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Coache Provost Report 2008, The Collaborative On Academic Careers In Higher Education (Coache), Harvard Graduate School Of Education Sep 2008

Coache Provost Report 2008, The Collaborative On Academic Careers In Higher Education (Coache), Harvard Graduate School Of Education

Survey Results

No abstract provided.

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Ultracapacitor Assisted Powertrains: Modeling, Control, Sizing, And The Impact On Fuel Economy, Dean Rotenberg Sep 2008

Ultracapacitor Assisted Powertrains: Modeling, Control, Sizing, And The Impact On Fuel Economy, Dean Rotenberg

All Theses

This thesis investigates possible fuel economy gains attainable by a combination of high-power density ultracapacitors (also called supercapacitors) and an induction motor integrated into a conventional vehicle powertrain for power assistance.
Periods of quick acceleration require a much higher power output from an automobile than what is encountered under more typical driving conditions. A simple kinetic energy calculation can show that accelerating a 2000 kg vehicle (roughly the size of a Ford Explorer SUV) from 0 to 60 mph in 10 seconds requires almost 70 kW of power, in addition to the power needed to overcome road and air drag …

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Fast Fourier Transform Algorithms With Applications, Todd Mateer Aug 2008

Fast Fourier Transform Algorithms With Applications, Todd Mateer

All Dissertations

This manuscript describes a number of algorithms that can be used to quickly evaluate a polynomial over a collection of points and interpolate these evaluations back into a polynomial. Engineers define the 'Fast Fourier Transform' as a method of solving the interpolation problem where the coefficient ring used to construct the polynomials has a special multiplicative structure. Mathematicians define the 'Fast Fourier Transform' as a method of solving the evaluation problem. One purpose of the document is to provide a mathematical treatment of the topic of the 'Fast Fourier Transform' that can also be understood by someone who has an …

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Accelerated Life Testing Of Electronic Revenue Meters, Venkata Chaluvadi Aug 2008

Accelerated Life Testing Of Electronic Revenue Meters, Venkata Chaluvadi

All Theses

Electricity meters are devices that continuously record electrical energy consumption. In the past, meters have been of electromechanical type and consisted windings and moving parts. Electromechanical meters tend to be bulky, less accurate and more susceptible to tampering. As with other aging power system infrastructure in the US, most electricity meters are around 40 years old and are nearing the end of their intended lifespan. Concerns over the accuracy of these electromechanical meters along with advances in technology have led to development of new electronic meters which have additional benefits such as light weight, tamper-proof mechanisms, harmonic detection and Advanced …

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Strategies For Expanding The Halogen Bonding Periodic Table And Desigining Complementary Halogen/Hydrogen Bonding Synthons, Hadi Arman Aug 2008

Strategies For Expanding The Halogen Bonding Periodic Table And Desigining Complementary Halogen/Hydrogen Bonding Synthons, Hadi Arman

All Dissertations

Halogen bonding is the donation of electron density from an electron donor, such as N, O, S, Se atoms, to an electron acceptor such as a dihalogen or organohalogen. This interaction plays an important role in biological systems, such as the thyroid gland and is useful in many other fields such as drug design, crystal engineering, synthetic chemistry, material science and bioinorganic chemistry. However, currently there is a lack of information for this interaction in systems involving organoiodines with sulfur and selenium electron donors.
A variety of sulfur and selenium Lewis base donors were investigated with various organoiodines. The main …

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Analysis, Instrumentation, And Visualization Of Embedded Network Systems: A Testbed-Based Approach, Andrew Dalton Aug 2008

Analysis, Instrumentation, And Visualization Of Embedded Network Systems: A Testbed-Based Approach, Andrew Dalton

All Dissertations

Embedded network systems are gaining adoption and emerging as the next step in the shift toward ubiquitous computing. Deployments range in scale from tens of devices to over a thousand; applications can be massively parallel and distributed, executing over unreliable links and devices. The programming model used to develop these systems is fundamentally different than the models provided by traditional imperative programming languages; many existing software engineering tools and techniques cannot be applied. In particular, the lack of tools and techniques to analyze, instrument, and visualize these systems make their development more difficult.
We present a framework to …

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Portfolio Selection Under Various Risk Measures, Hariharan Kandasamy Aug 2008

Portfolio Selection Under Various Risk Measures, Hariharan Kandasamy

All Dissertations

Portfolio selection has been a major area of study after Markowitz's ground-breaking paper. Risk quantification for portfolio selection is studied in the literature extensively and many risk measures have been proposed.
In this dissertation we study portfolio selection under various risk measures. After exploring important risk measures currently available we propose a new risk measure, Unequal Prioritized Downside Risk (UPDR). We illustrate the formulation of UPDR for portfolio selection as a mixed-integer program. We establish conditions under which UPDR can be formulated as a linear program.
We study single-period portfolio selection using two risk measures simultaneously. We propose four alternate …

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Numerical Analysis Of A Fractional Step Theta-Method For Fluid Flow Problems, John Chrispell Aug 2008

Numerical Analysis Of A Fractional Step Theta-Method For Fluid Flow Problems, John Chrispell

All Dissertations

The accurate numerical approximation of viscoelastic fluid flow poses two difficulties: the large number of unknowns in the approximating algebraic system (corresponding to velocity, pressure, and stress), and the different mathematical types of the modeling equations. Specifically, the viscoelastic modeling equations have a hyperbolic constitutive equation coupled to a parabolic conservation of momentum equation. An appealing approximation approach is to use a fractional step $\theta$-method. The $\theta$-method is an operator splitting technique that may be used to decouple mathematical equations of different types as well as separate the updates of distinct modeling equation variables when modeling mixed systems of partial …

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Design And Validation Of A Multimethod Assessment Of Metacognition And Study Of The Effectiveness Of Metacognitive Interventions, Guillermo Sandi-Urena Aug 2008

Design And Validation Of A Multimethod Assessment Of Metacognition And Study Of The Effectiveness Of Metacognitive Interventions, Guillermo Sandi-Urena

All Dissertations

The central role of metacognition in learning and problem solving, in general and in chemistry in specific, has been substantially demonstrated and has raised pronounced interest in its study. However, the intrinsic difficulties associated with the inner processes of such a non-overt behavior have delayed the development of appropriate assessment instruments. The first research question addressed in this work originates from this observation: Is it possible to reliably assess metacognition use in chemistry problem solving? This study presents the development, validation, and application of a multimethod instrument for the assessment of metacognition use in chemistry problem solving. This multimethod is …

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Lead Chalcogenide Nano-Composites: Synthesis, Thermal And Electrical Transport Properties, Bo Zhang Aug 2008

Lead Chalcogenide Nano-Composites: Synthesis, Thermal And Electrical Transport Properties, Bo Zhang

All Dissertations

This dissertation focused on the investigation of the thermoelectric properties of PbTe nanocomposites, presenting a series of experimental investigation and qualitative theoretical analysis regarding utilizing the nanostructures to enhance the thermoelectrical properties. Three innovative synthesis techniques, which are related to fabricating nanocomposites, were developed. These three techniques are the size-selective growth of PbTe nanoparticles by a convection CVD technique, the nanolayer coating technique by hydrothermal method, and the alkali-metal-nano-surface-treatment. In the future, these techniques can be applied to many other thermoelectric material systems.

We proposed to use the grain boundary engineering technique route in the thermoelectric nanocomposite field and successfully …

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Performance Based Decisions Under Uncertainty And Risk, Sundeep Samson Aug 2008

Performance Based Decisions Under Uncertainty And Risk, Sundeep Samson

All Dissertations

Decision making has became increasingly complex as risky decisions are made in uncertain environments. To minimize risk, the problem of quantifying risk becomes very significant. In our review of the literature, we found a number of different risk measures. A closer study reveals that most of these risk measures define both risk and uncertainty in many different ways.
In this dissertation, we model uncertainty and risk based on the Knightian definition of uncertainty and risk. We propose this alternative modeling paradigm and introduce our decision making methodology by solving an illustrative problem presented by a group of decision makers from …

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3-D Calculation Of Atom-Surface Collisions With Direct Scattering, Trapping And Desorption, Guoqing Fan Aug 2008

3-D Calculation Of Atom-Surface Collisions With Direct Scattering, Trapping And Desorption, Guoqing Fan

All Dissertations

In this work a scattering theory is developed to simulate the gas-surface scattering procedure in three dimensions, using an iterative algorithm and classical mechanics for the collision process, that describes both direct scattering and trapping-desorption of an incident beam of atomic particles. The initially trapped fraction of particles can be followed as they continue to make further collisions with the surface until they are all eventually promoted back into the positive energy continuum and leave the surface region.

With two different models, the discrete model and the smooth-surface model of the differential reflection coefficient, a series of calculation are made …

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Structure And Transport Characteristics Of Highly Rigid Ionomers, Lilin He Aug 2008

Structure And Transport Characteristics Of Highly Rigid Ionomers, Lilin He

All Dissertations

The structure and transport characteristics in a novel family of ionomers consisting of a hydrophobic polyphenylene backbone substituted by sulfonic acid functionalized phenyl side chains (sPPs) have been investigated. These polymers have potential applications in electrochemistry as well as separation both as membranes and thin films. The bulk structure as a function of hydration has been explored by X-ray and neutron scattering. Interfacial structure was studied by AFM and neutron reflectometry. The characteristics of water in the bulk were studied by NMR and FTIR and that in thin films by neutron reflectometry.

The sPPs exhibit characteristic structure due to their …

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Modeling Systems For Optimal Resource Allocation, Scheduling, And Decision Making, Esengul Tayfur Aug 2008

Modeling Systems For Optimal Resource Allocation, Scheduling, And Decision Making, Esengul Tayfur

All Dissertations

This dissertation focuses on the resource requirements and scheduling problem for logistic systems. We investigate solutions to this problem in two different logistic systems: logistic system of the health care facilities during emergency evacuations and delivery and distribution system of production industries. All hospitals must have an evacuation plan to ensure the safety of patients and prevent the loss of life. However, hospital operators have not been able to quantify how resource availability, the cost of acquiring those resources, and evacuation completion time are related. This research addresses this problem and contributes two methodologies to solve this problem. In the …

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The Effects Of Nanoparticle Inclusions Upon The Microstructure And Thermoelectric Transport Properties Of Bismuth Telluride-Based Composites, Nick Gothard Aug 2008

The Effects Of Nanoparticle Inclusions Upon The Microstructure And Thermoelectric Transport Properties Of Bismuth Telluride-Based Composites, Nick Gothard

All Dissertations

Research into materials that have high efficiencies of thermoelectric heat-energy conversion has been at a plateau since the middle of the last century. During this time, efficiencies have been engineered high enough for several interesting niche applications but not high enough for widespread adaptation into traditional power generation or refrigeration technologies. The past decade has seen considerable advancement as a number of theoretical works have suggested that lower dimensional structures could hold the key for enhanced efficiency, and several experiments have provided the proof of principle needed to inspire just such a research direction. The benefit of low dimensional structures …

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Inferring Mechanical Resonances In Micro - And Nanocantilevers Using The Harmonic Detection Of Resonance (Hdr) Method To Develop A Novel Sensing Platform, Gayatri Keskar Aug 2008

Inferring Mechanical Resonances In Micro - And Nanocantilevers Using The Harmonic Detection Of Resonance (Hdr) Method To Develop A Novel Sensing Platform, Gayatri Keskar

All Dissertations

During the past two decades, advances in microelectromechanical systems (MEMS) have spurred efforts worldwide to develop sensing platforms based on smart microcantilevers. A microcantilever beam is one of the simplest MEMS structures which forms the basis for portable, fast and highly sensitive schemes that are capable of measuring small deflections in static or dynamic response due to changes in external parameters such as mass, pressure, charge, etc.
In this dissertation, I mainly focus on MEMS sensors with transducers in the form of microcantilevers. Variations in the microcantilever's response such as resonant frequency, amplitude, phase and quality factor when exposed to …

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Revenue And Order Management Under Demand Uncertainty, Kiran Chahar Aug 2008

Revenue And Order Management Under Demand Uncertainty, Kiran Chahar

All Dissertations

We consider a firm that delivers its products across several customers or markets, each with unique revenue and uncertain demand size for a single selling season. Given that the firm experiences a long procurement lead time, the firm must decide, far in advance of the selling season not only the markets to be pursued but also the procurement quantity. In this dissertation, we present several operational scenarios in which the firm must decide which customer demands to satisfy, at what level to satisfy each customer demand, and how much to produce (or order) in total.
Traditionally, a newsvendor approach to …

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Electrochemical Synthesis And Characterization Of Polymers From Bis(3,4-Ethylenedioxythiophene)-Thiophenes (Bedot-Ts) And Bis(3,4-Ethylenedioxythiophene)-Benzenes (Bedot-Bs) As Optoelectronic Materials, Kalya Eaiprasertsak Aug 2008

Electrochemical Synthesis And Characterization Of Polymers From Bis(3,4-Ethylenedioxythiophene)-Thiophenes (Bedot-Ts) And Bis(3,4-Ethylenedioxythiophene)-Benzenes (Bedot-Bs) As Optoelectronic Materials, Kalya Eaiprasertsak

All Dissertations

ABSTRACT


A series of bis(3,4-ethylenedioxythiophene)-thiophene derivatives (BEDOT-Ts) and bis(3,4-ethylenedioxythiophene)-benzene derivatives (BEDOT-Bs) monomers were electrochemically polymerized onto glassy carbon or ITO-coated glass electrodes. Cyclic voltammetry (CV), infrared (IR), UV-vis-NIR and photoluminescence (PL) spectroscopy were employed to investigate and characterize properties of resulting polymers. dc-conductivities of these polymers were measured by the four-point probe method.
Cyclic voltammetry studies show that the redox half potentials of PBEDOT-3BT, PBEDOT-3OT, PBEDOT-3TBS and PBEDOT-3MPT are -290, -297, -325 and -284 mV versus Ag/Ag+, respectively. The redox half potentials of PBEDOT-TOL, PBEDOT-BOB and PBEDOT-FB are -130, -147 and -327 mV vs. Ag/Ag+, respectively, and a bit higher …

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Synthesis, Electronic Structure, And Reactivity Of Endohedral Metallofullerenes And Other Endohedral Carbon Nanostructures, Bevan Elliott Aug 2008

Synthesis, Electronic Structure, And Reactivity Of Endohedral Metallofullerenes And Other Endohedral Carbon Nanostructures, Bevan Elliott

All Dissertations

The discovery in 1985 of fullerenes combined with the development of STM beginning in 1981 is credited as the starting point of the current nanoscience revolution. Endohedral fullerenes, discovered shortly after, have drastically different electronic properties when compared with the empty fullerenes. This dissertation has as its central focus the synthesis and electronic properties of endohedral metallofullerenes and other endohedral nanostructures.
The opening two chapters give a brief background of the discovery of fullerenes. A comprehensive literature list is given for the various families of trimetallic nitride endohedral fullerenes as well as other large endohedral metallic cluster fullerenes. Finally, a …

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Homomorphisms Of Graphs, Samuel Lyle Aug 2008

Homomorphisms Of Graphs, Samuel Lyle

All Dissertations

Understanding the structure of graphs is fundamental to advances in many areas of graph theory, as well as in many applications. In many cases, an analysis of the structure of graphs follows one of two approaches; either many structural properties are considered over a restricted class of graphs, or a particular structural property is considered over many classes of graphs. Both approaches will be considered in this dissertation.
Graphs which do not contain a clique of size r, i.e., Kr-free graphs, are of fundamental importance in the area of extremal graph theory. Many results have been obtained …

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Synthesis And Pharmacology Of N-Alkyl-3-(Halo-Naphthoyl)Indoles, Valerie Smith Aug 2008

Synthesis And Pharmacology Of N-Alkyl-3-(Halo-Naphthoyl)Indoles, Valerie Smith

All Dissertations

The medicinal values of marijuana have often been overshadowed due to the psychotropic, 'recreational' effects it brings about in a user. For hundreds of years the therapeutic uses of cannabis sativa were appreciated, but the inability to control the dosage of the main constituent, and therefore the psychotropic effects, rendered the drug a liability. The elucidation of the structure of this main psychoactive constituent, ∆9-tetrahydrocannabinol (∆9-THC) by Gaoni and Mechoulam in 1964 opened the door to the discovery of a vast array of knowledge about cannabinoids. From the multiple classes of cannabinoids and the ways these compounds interact with the …

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