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2007

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Evaluation Of Mvct Images With Skin Collimation For Electron Treatment Planning, Allen Beardmore Jan 2007

Evaluation Of Mvct Images With Skin Collimation For Electron Treatment Planning, Allen Beardmore

LSU Master's Theses

Purpose: To evaluate the accuracy of electron beam dose calculations in MVCT images containing lead alloy masks. Method and Materials: A phantom consisting of two 30x30x5 cm3 slabs of CIRS plastic water® was imaged using kVCT (GE Lightspeed-RT) and MVCT (TomoTherapy Hi·Art). Nine MVCT scans were taken with different square masks of lead alloy (Cerrobend®, density = 9.4 g·cm-3) on top of the phantom. The masks contained square apertures of 3x3 cm2, 6x6 cm2 and 10x10 cm2 and had thicknesses of 6 mm, 8 mm and 10 mm. The same collimation was simulated …

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Wet And Dry Aging Of Polymer-Asphalt Blends: Chemistry And Performance, Ionela Chiparus Glover Jan 2007

Wet And Dry Aging Of Polymer-Asphalt Blends: Chemistry And Performance, Ionela Chiparus Glover

LSU Doctoral Dissertations

A PG 76-22 Polymer Modified Asphalt Cement composition was subjected in the laboratory to accelerated aging using both a standard Thin Film Oven Test and a Pressure Aging Vessel. Conditions simulating wet atmospheres (PAV in saturated water vapors) as well as very long service terms (multiple dry and wet PAV operations) were studied. A Rotating Cylinder Aging Test has been employed as an alternate asphalt aging technique using the same PMAC composition in order to observe the initial phases of the oxidative aging process. The data provided by this technique was correlated with the actual aging in the field of …

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The Application Of Controlled Radical Polymerization Processes On The Graft Copolymerization Of Hydrophobic Substituents Onto Guar Gum And Guar Gum Derivatives, Veronica Holmes Jan 2007

The Application Of Controlled Radical Polymerization Processes On The Graft Copolymerization Of Hydrophobic Substituents Onto Guar Gum And Guar Gum Derivatives, Veronica Holmes

LSU Doctoral Dissertations

Guar gum is a naturally occurring polysaccharide; guar gum and its derivatives, such as carboxymethyl guar gum (CMG) are widely used in the oil and gas industry. A hydraulic fracturing fluid for rock formations to enhance oil recovery (EOR) is comprised of viscosifier, gelled CMG, and sand particles (proppants). The gel is mixed with proppant (sand) and pumped at high rate and high pressure into an oil/gas well to the hydrocarbon-producing zone. The applied pressure will force the rock formation to fracture allowing entry of the guar gel/sand mixture. The mixture then fills the resultant fracture. The viscosity of the …

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Optimal Control Of Production And Distribution In A Supply Chain System Operating Under A Jit Delivery Policy, Pablo Biswas Jan 2007

Optimal Control Of Production And Distribution In A Supply Chain System Operating Under A Jit Delivery Policy, Pablo Biswas

LSU Doctoral Dissertations

This research deals with a supply chain system where the production or manufacturing facility operates under a just-in-time (JIT) environment, and the facility consists of raw material suppliers, manufacturers, and retailers where inventory of raw materials, work-in-process, and finished goods are involved, respectively. This work considers that the production of finished goods in one cycle starts just after the production or uptime in preceding cycle to minimize the idle time of the facility. Considering this scenario, inventory models are developed for different delivery situations: (a) perfect matching condition where no finished good remains after the shipments and (b) imperfect matching …

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Comparison Of Kp And Bbm-Kp Models, Gideon Pyelshak Daspan Jan 2007

Comparison Of Kp And Bbm-Kp Models, Gideon Pyelshak Daspan

LSU Doctoral Dissertations

In this dissertation we show that the solution of the pure initial-value problems for the KP and regularize KP equations are the same, to within the order of accuracy attributable to either, on the time scale from zero to epsilon to negative three halves power, during which nonlinear and dispersive effects may accumulate to make an order-one relative difference to the wave profiles.

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The Aggregate Harmony Metric And A Statistical And Visual Contextualization Of The Rehnquist Court: 50 Years Of Data, Peter A. Hook Jan 2007

The Aggregate Harmony Metric And A Statistical And Visual Contextualization Of The Rehnquist Court: 50 Years Of Data, Peter A. Hook

Articles by Maurer Faculty

This article contains aggregated data from fifty years of the annual matrixes of justice inter-agreement for particular Supreme Court terms published by the Harvard Law Review (1956 to 2005 terms). Aggregating how often any two justices sided together on cases for a particular term relative to the amount of cases the two justices heard together allows one to derive a measure of the particular term that reflects the relative amount of agreement or disagreement for the term. This new metric, called the Aggregate Harmony Metric, allows for comparative benchmarks. For instance, the 2005 term, with an aggregate agreement of 70%, …

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Pile Capacity Utilization For Bridge Bents Designed Using Simplified Procedures, Md Rubiat Ferdous Jan 2007

Pile Capacity Utilization For Bridge Bents Designed Using Simplified Procedures, Md Rubiat Ferdous

LSU Master's Theses

Bent substructure systems are being used increasingly in bridge construction. Among the various bent systems, pile bents are considered a popular choice due to their effectiveness in reducing time and cost. They are constructed by first driving piles to a specified elevation above the ground surface. Then, a cast-in-place reinforced concrete bent cap ties the piles together at their top end. The current Louisiana Department of Transportation and Development Bridge Design Manual provides guidelines for the structural analysis and construction details for general use in the preparation of plans for pile bents. The manual allows the use of a simplified …

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An Investigation Of The Frictional And Thermal Behavior Of Oscillatory Sliding Line Contacts, Mongi Mansouri Jan 2007

An Investigation Of The Frictional And Thermal Behavior Of Oscillatory Sliding Line Contacts, Mongi Mansouri

LSU Doctoral Dissertations

This research deals with an experimental and numerical investigation of the frictional and thermal behavior of pin-bushing pairs, operating at reciprocating sliding motion or under heavy loads. Large interfacial temperatures developed due to frictional heating can cause failure. Therefore, numerical prediction and analysis of the surface temperature under various operating conditions are important. Laboratory tests using a pin-bushing tester provided measurements of the friction coefficient and temperature. Hard coated and plain (uncoated) bushings, both made of induction hardened stainless steel, were tested. Lower coefficient of friction and surface temperature were observed in the case of the coated bushing. In the …

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Chiral Analyses Using Molecualr Micelles And Multiple Regression Modeling In Chromatographic And Spectroscopic Methods, Alicia Williams Snearl Jan 2007

Chiral Analyses Using Molecualr Micelles And Multiple Regression Modeling In Chromatographic And Spectroscopic Methods, Alicia Williams Snearl

LSU Doctoral Dissertations

Multiple regression modeling techniques allow for rapid and accurate prediction of migration times and resolution values for micellar electrokinetic chromatography (MEKC) as well as the development of quick screening methods using steady-state fluorescence spectroscopy. All studies reported in this dissertation include optimization of calibration models and predictions of dependent variables by the use of validation samples. The root-mean-square percent relative error (RMS%RE) is used as a figure of merit for characterizing the performance of the calibration models. MEKC separations of achiral and chiral analytes were performed using an achiral molecular micelle, poly(sodium N-undecylenic sulfate), and chiral molecular micelles, poly(sodium N-undecanoyl-L-leucylvalinate) …

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Demographic And Psychological Factors Influencing Academic Success In A College Level Human Anatomy Course, Wanda Green Hargroder Jan 2007

Demographic And Psychological Factors Influencing Academic Success In A College Level Human Anatomy Course, Wanda Green Hargroder

LSU Doctoral Dissertations

The primary purpose of this study was to determine the influence of selected demographic and psychological characteristics on the academic achievement of students enrolled in an undergraduate human anatomy course at a research-extensive university in the Southern region of the United States. As health care in the United States becomes increasingly strained due to a decreasing ratio of health care workers, educating more students to fill this gap has become a societal issue. Human anatomy forms the foundation of all health care professions. From the molecular to the macroscopic, anatomy provides a unique and necessary perspective of the human body. …

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University Of Pennsylvania Ms Codex 436: A Description And Analysis Of Contents, Jeannette Di Bernardo Jones Jan 2007

University Of Pennsylvania Ms Codex 436: A Description And Analysis Of Contents, Jeannette Di Bernardo Jones

LSU Master's Theses

The University of Pennsylvania Ms. Codex 436, an Italian manuscript dated 1682, is a handbook containing alphabets, linguistic treatises, a computus for calculating the date of Easter, mathematical tables, and rules for music theory and singing the liturgy. The manuscript's contents make it possible to identify the compiler as a student; the contents, along with their mode of presentation and the manuscript's general appearance, make it possible to situate him within the culture of humanism and more specifically within book culture in the transition from manuscript to print. The contents indicate who the compiler is in terms of his social …

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Dna Multiplex Hybridization On Microarrays And Thermodynamic Stability In Solution: A Direct Comparison, Daniel J. Fish, M. Todd Horne, Greg P. Brewood, Jim P. Goodarzi, Saba Alemayehu, Ashwini Bhandiwad, Robert P. Searles, Albert S. Benight Jan 2007

Dna Multiplex Hybridization On Microarrays And Thermodynamic Stability In Solution: A Direct Comparison, Daniel J. Fish, M. Todd Horne, Greg P. Brewood, Jim P. Goodarzi, Saba Alemayehu, Ashwini Bhandiwad, Robert P. Searles, Albert S. Benight

Chemistry Faculty Publications and Presentations

Hybridization intensities of 30 distinct short duplex DNAs measured on spotted microarrays, were directly compared with thermodynamic stabilities measured in solution. DNA sequences were designed to promote formation of perfect match, or hybrid duplexes containing tandem mismatches. Thermodynamic parameters DeltaH degrees , DeltaS degrees and DeltaG degrees of melting transitions in solution were evaluated directly using differential scanning calorimetry. Quantitative comparison with results from 63 multiplex microarray hybridization experiments provided a linear relationship for perfect match and most mismatch duplexes. Examination of outliers suggests that both duplex length and relative position of tandem mismatches could be important factors contributing to …

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Passive Alignment Of Micro-Fluidic Chips Using The Principle Of Elastic Averaging, Sitanshu Gurung Jan 2007

Passive Alignment Of Micro-Fluidic Chips Using The Principle Of Elastic Averaging, Sitanshu Gurung

LSU Master's Theses

This thesis presents a novel design for a passive alignment feature for vertically stacking chips in a micro fluidic device. Each chip is the size of a standard microscopic slide (75mm—25mm) and is a highly specialized functional unit designed and fabricated to process fluidic samples. The fluidic samples in the device flows from one chip to another using inter connecting holes 500μm-100μm in diameter. Hence an alignment of better than 100μm between chips is necessary to allow for the interconnecting holes to overlap so as to provide with a path for the fluid to flow. The feature to be used …

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Technology Adoption Of Indian Garment Manufacturing Firms, Venu Varukolu Jan 2007

Technology Adoption Of Indian Garment Manufacturing Firms, Venu Varukolu

LSU Master's Theses

The purpose of this study is to investigate the status and the effect of organizational factors on the level of technology adoption within the context of the Indian garment industry. Specifically, this study focuses on the effect of firm size, export orientation, top management’s commitment, cost of capital, technical skills, and competitive advantage. An online survey using a structured questionnaire was prepared through an online research service. A multiple regression analysis (MRA) was used to test the hypotheses. The results revealed that firm size positively influences and export orientation negatively influences the technology adoption level of a firm. The effect …

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Transcendental Eigenvalue Problems Associated With Vibration, Buckling And Control, Jayaram Subramanian Jan 2007

Transcendental Eigenvalue Problems Associated With Vibration, Buckling And Control, Jayaram Subramanian

LSU Master's Theses

The static and dynamic analysis of structures requires us to obtain solutions of their espective governing differential equations subject to appropriate boundary conditions. The dynamic analysis of non-uniform continuous structures is of primary interest, as most traditional methods take the help of discrete models to analyze them. Well established discrete model methods lead to an algebraic eigenvalue problem, the characteristic equation associated with which is a polynomial. The spectral characteristics of a continuous system nevertheless are represented by transcendental functions and cannot be approximated by polynomials efficiently. Hence finite dimensional discrete models are not capable of predicting the response of …

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Predictive Data Compression Using Adaptive Arithmetic Coding, Claudio Jose Iombo Jan 2007

Predictive Data Compression Using Adaptive Arithmetic Coding, Claudio Jose Iombo

LSU Master's Theses

The commonly used data compression techniques do not necessarily provide maximal compression and neither do they define the most efficient framework for transmission of data. In this thesis we investigate variants of the standard compression algorithms that use the strategy of partitioning of the data to be compressed. Doing so not only increases the compression ratio in many instances, it also reduces the maximum data block size for transmission. The partitioning of the data is made using a Markov model to predict if doing so would result in increased compression ratio. Experiments have been performed on text files comparing the …

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Flow Field And Heat Transfer Analyses Of Mechanical Seals, Zhaogao Luan Jan 2007

Flow Field And Heat Transfer Analyses Of Mechanical Seals, Zhaogao Luan

LSU Doctoral Dissertations

Mechanical seals are widely used in rotating equipment such as pumps, turbines and agitators to prevent leakage. One crucial factor for keeping seals reliable is the thermal behavior of the seal rings. The existing literature on thermal effects in seals primarily concentrates on the conduction of heat into the rings. Yet, a more complete analysis requires understanding of the flow field around the rings. In this dissertation, both the laminar and turbulent flows within the seal chamber are studied and their effects on the heat transfer in the seal rings are evaluated. Based on extensive sets of numerical simulations, heat …

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The Art Of Perception: Robert Irwin's Central Garden At The J. Paul Getty Center, Jennifer Kay Zell Jan 2007

The Art Of Perception: Robert Irwin's Central Garden At The J. Paul Getty Center, Jennifer Kay Zell

LSU Master's Theses

In this study of The Central Garden at the J. Paul Getty Center was found evidence that the Central Garden designed by Robert Irwin is a postmodern garden. Beginning with an evaluation and description of the individual elements and conditions of the garden, the study then explores the larger body of artistic work produced by Irwin. This investigation also extrapolates how the ideas of modernism and postmodernism have been applied to past works of landscape architecture. The precedents provide a basis for interpretation and analysis of the Central Garden. Direct observation of visitors at the Central Garden provided evidence of …

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Glacial Deposits, Vol. 35, 2006-2007, Department Of Geography-Geology Jan 2007

Glacial Deposits, Vol. 35, 2006-2007, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology

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Effects Of Aversive Conditioning On Behavior Of Nuisance Louisiana Black Bears, Jennifer Leigh Jan 2007

Effects Of Aversive Conditioning On Behavior Of Nuisance Louisiana Black Bears, Jennifer Leigh

LSU Master's Theses

Consistent habitat loss and fragmentation are contributing factors to the rise of human-bear conflicts in south Louisiana. Complaints associated with nuisance activities of Louisiana black bears (Ursus americanus luteolus) experienced in this region have steadily increased since 2000, requiring intervention by state and federal agencies. As a threatened species, Louisiana black bears require non-lethal management referred to as aversive conditioning. We used rubber buckshot and dogs to test the effectiveness of management techniques used by the state to deter nuisance activity by black bears. Eleven bears, representing approximately 15% of the estimated population in this region, were captured in residential …

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Identifying Effective And Ineffective Schools For Accountability Purposes: A Comparison Of Four Generic Types Of Accountability Models, Fen Yu Jan 2007

Identifying Effective And Ineffective Schools For Accountability Purposes: A Comparison Of Four Generic Types Of Accountability Models, Fen Yu

LSU Doctoral Dissertations

The stakes associated with student performance have been raised to new highs under the No Child Left Behind Act (NCLB, 2001). Many people are concerned with the adequacy and appropriateness of the statistical models used in identifying low-performing schools for educational accountability. The purpose of this study was to compare four generic types of accountability models (i.e., status models, improvement models, growth models, and value-added models) and see if they reach consistent/inconsistent conclusions regarding the effectiveness of the same set of schools. Further, the four models were also compared in terms of “fairness”. A fair model is defined as one …

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Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang Jan 2007

Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang

LSU Doctoral Dissertations

Useful mechanistic studies to date concerning sugar detection by arylboronic acid chemosensors have mainly involved the elucidation of equilibrium constants and the role of boron-nitrogen interactions in signal transduction. However, several discreet sugarboronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. Relatively few reports have been devoted to a systematic study of the structures of each of the corresponding individual sugar-boronate complexes. We have investigated some of the precise regio- and stereochemical features of the various equilibrating sugar isomers that induce selective signal transduction. As a result of this …

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Synthesis Of Quaternary Dendronized Cellulose Derivatives And Their Potential Biological Applications, Changde Zhang Jan 2007

Synthesis Of Quaternary Dendronized Cellulose Derivatives And Their Potential Biological Applications, Changde Zhang

LSU Doctoral Dissertations

In this dissertation, novel dendronized cellulose derivatives with biodegradable backbones were created by using sodium carboxymethyl cellulose (CMC) as the starting material. CMC was first transformed into its corresponding tetrabutyl ammonium salt, which reacted with 2-chloro-N-methylpyridinium iodide (CMPI) to produce an activated ester of [2-(N-methyl pyridium) carboxymethyl cellulose] iodide (MPCMCI). The reaction of MPCMCPI and di-tert-butyl 4-[2-(ter-butoxycarbonyl)ethyl]-4-aminoheptanedicarboxylate (BA) produced a new derivative with BA dendron elaborated on cellulose backbone (CMCBA). The degree of substitution (DS) of CMCBA was adjusted by controlling the relative concentration of CMPI and by choosing CMC with different DS or different molecular weights. Thermogrametric analysis (TGA) …

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Measurement Of Metal Migration In Sediment Caps With X-Ray Fluorescene, Ming Yin Jan 2007

Measurement Of Metal Migration In Sediment Caps With X-Ray Fluorescene, Ming Yin

LSU Doctoral Dissertations

ABSTRACT Sand is often used as a passive barrier to slow release of metals from the sediment and to separate benthic organisms from the sediment. Materials that effectively adsorb metals have the potential to provide significantly greater effectiveness by further retarding metal release. In this thesis, the effectiveness of apatite and Phosphil®, which contain phosphate in a form that can absorb many metals, is evaluated with a series of sorption and migration column experiments using Cr, Cu, Zn and Pb. Langmuir shape isotherms were observed suggesting that the effectiveness of these materials decreases at high concentration. The sorption isotherm experiments …

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Synthesis And Evaluation Of Derivatives And Analogs Of Xanthene Dyes, Xiangyang Xu Jan 2007

Synthesis And Evaluation Of Derivatives And Analogs Of Xanthene Dyes, Xiangyang Xu

LSU Doctoral Dissertations

Xanthene dyes are one of the oldest synthetic dyes. Fluorescein was first synthesized by von Baeyer in 1871. Since its discovery, it has been extensively studied. Fluorescein can exist as four different ionic forms (cationic form, neutral form, monoanionic form and dianionic form). Under physiological conditions (pH 7.4), fluorescein mainly exists as the dianionic form which grants it large quantum yield and excellent solubility in water. This renders fluorescein and its derivatives useful for studies in biological media. Cysteine (Cys) and homocysteine (Hcy) are of the few amino acids which contain sulfur and both of them are believed to be …

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Book Review. All Politics Is Global: Explaining International Regulatory Regimes By Daniel W. Drezner, David Fidler Jan 2007

Book Review. All Politics Is Global: Explaining International Regulatory Regimes By Daniel W. Drezner, David Fidler

Articles by Maurer Faculty

No abstract provided.

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Rna:Dna As An Indicator Of Nutritional Condition And Growth In Larval Naked Goby, Gobiosoma Bosc, Michelle C. Satterwhite Jan 2007

Rna:Dna As An Indicator Of Nutritional Condition And Growth In Larval Naked Goby, Gobiosoma Bosc, Michelle C. Satterwhite

LSU Master's Theses

Developing organism-based metrics for assessing habitat quality is an important tool in conservation and restoration of aquatic habitats. The use of the RNA:DNA ratio as an early indicator of habitat effects on growth of nekton species has been suggested, but requires species-specific laboratory assessment prior to field application. We used food availability in laboratory treatments to simulate differences in habitat quality. Wild Gobiosoma bosc eggs were collected using nest-traps constructed of PVC pipe. Eggs from several different nests collected in the field were hatched in the lab, yielding larvae that were randomly assigned to three feeding treatments in two replicate …

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Experimental Investigation Of An Electronically Collimated Radiation Detector For Location Of Gamma-Ray Sources, William H. Hill Jr. Jan 2007

Experimental Investigation Of An Electronically Collimated Radiation Detector For Location Of Gamma-Ray Sources, William H. Hill Jr.

LSU Master's Theses

A electronically collimated prototype detector was built with commercially available cadmium zinc telluride (CZT) modules and assessed by experiment and simulation. Sensitivity was roughly equivalent to a common hand held 1"x1" NaI(Tl) detector. The maximum useful count rate was 300 counts per second (cps) per module. Overall angular error was less than 7°, which is generally less than source placement uncertainty, and angular resolution was between 20° and 40° for several common isotopes with photon energies between 511 keV and 1333 keV. Prototype data and backprojections were used to verify a simple three dimensional model of charge induction in pixellated …

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The Education Of Princess Mary Tudor, Katherine Lee Pierret Perkins Jan 2007

The Education Of Princess Mary Tudor, Katherine Lee Pierret Perkins

LSU Master's Theses

Mary Tudor, the first officially crowned queen regnant of England, received a humanist education. A curriculum was recommended for her in multiple writings by Spanish humanist Juan Luis Vives. This thesis attempts to synthesize and examine information the nature of this plan for a princess's education and the extent to which it was implemented.

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Exploring The Quark-Gluon Content Of Hadrons: From Mesons To Nuclear Matters, Hrayr Hamlet Matevosyan Jan 2007

Exploring The Quark-Gluon Content Of Hadrons: From Mesons To Nuclear Matters, Hrayr Hamlet Matevosyan

LSU Doctoral Dissertations

Even though Quantum Chromodynamics (QCD) was formulated over three decades ago, it poses enormous challenges for describing the properties of hadrons from the underlying quark-gluon degrees of freedom. Moreover, the problem of describing the nuclear force from its quark-gluon origin is still open. While a direct solution of QCD to describe the hadrons and nuclear force is not possible at this time, we explore a variety of developed approaches ranging from phenomenology to first principle calculations at one or other level of approximation in linking the nuclear force to QCD. The Dyson Schwinger formulation (DSE) of coupled integral equations for …

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