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Part I : Isolation Of Dipentyl 2-(4-(Pentan-3-Yl) Phenyl) Malonate From Sanguisorba Officinalis Labill Part Ii: Synthesis Of A Novel Family Of Ethers Of Podocarpic Acid, Manjeera Yalavarty Jan 2005

Part I : Isolation Of Dipentyl 2-(4-(Pentan-3-Yl) Phenyl) Malonate From Sanguisorba Officinalis Labill Part Ii: Synthesis Of A Novel Family Of Ethers Of Podocarpic Acid, Manjeera Yalavarty

Electronic Theses and Dissertations

The goal of part I of this thesis was to isolate pure anti cancer compounds from the Russian plant Sanguisorba officinalis. This plant was selected for investigation because it showed 100% activity against leukemia (L1210 mouse leukemia cells) during the preliminary screening of approximately 100 Russian plant extracts. This work has resulted in the isolation of novel compound 11 using traditional chromatography techniques. Compound 11 was characterized with spectroscopic techniques such as IR, 1H NMR, 13C NMR, DEPT, DQCOSY and MS. Compound 11 was assigned the structure dipentyl 2-(4-(pentan-3-yl) phenyl) malonate. The goal of part II of this thesis was …

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Planning And Scheduling For Large-Scaledistributed Systems, Han Yu Jan 2005

Planning And Scheduling For Large-Scaledistributed Systems, Han Yu

Electronic Theses and Dissertations

Many applications require computing resources well beyond those available on any single system. Simulations of atomic and subatomic systems with application to material science, computations related to study of natural sciences, and computer-aided design are examples of applications that can benefit from the resource-rich environment provided by a large collection of autonomous systems interconnected by high-speed networks. To transform such a collection of systems into a user's virtual machine, we have to develop new algorithms for coordination, planning, scheduling, resource discovery, and other functions that can be automated. Then we can develop societal services based upon these algorithms, which hide …

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Graph-Theoretic Approach To Modeling Propagation And Control Of Network Worms, Zoran Nikoloski Jan 2005

Graph-Theoretic Approach To Modeling Propagation And Control Of Network Worms, Zoran Nikoloski

Electronic Theses and Dissertations

In today's network-dependent society, cyber attacks with network worms have become the predominant threat to confidentiality, integrity, and availability of network computing resources. Despite ongoing research efforts, there is still no comprehensive network-security solution aimed at controling large-scale worm propagation. The aim of this work is fivefold: (1) Developing an accurate combinatorial model of worm propagation that can facilitate the analysis of worm control strategies, (2) Building an accurate epidemiological model for the propagation of a worm employing local strategies, (3) Devising distributed architecture and algorithms for detection of worm scanning activities, (4) Designing effective control strategies against the worm, …

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Super High-Speed Miniaturized Permanent Magnet Synchronous Motor, Liping Zheng Jan 2005

Super High-Speed Miniaturized Permanent Magnet Synchronous Motor, Liping Zheng

Electronic Theses and Dissertations

This dissertation is concerned with the design of permanent magnet synchronous motors (PMSM) to operate at super-high speed with high efficiency. The designed and fabricated PMSM was successfully tested to run upto 210,000 rpm The designed PMSM has 2000 W shaft output power at 200,000 rpm and at the cryogenic temperature of 77 K. The test results showed the motor to have an efficiency reaching above 92%. This achieved efficiency indicated a significant improvement compared to commercial motors with similar ratings. This dissertation first discusses the basic concept of electrical machines. After that, the modeling of PMSM for dynamic simulation …

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Adapting The Modified Cam Clay Constitutive Model To The Computational Analysis Of Dense Granular Soils, Jose Arvelo Jan 2005

Adapting The Modified Cam Clay Constitutive Model To The Computational Analysis Of Dense Granular Soils, Jose Arvelo

Electronic Theses and Dissertations

The computational constitutive Modified Cam Clay Model (MCCM) was developed at Cambridge to study the behavior of clays and has been proven to be effective. In this study, this model is extended to the case of dense sands to analyze the accuracy of the stress-strain behavior. This analysis is based on triaxial test data applied to remolded and compacted sand samples under drained conditions. The laboratory triaxial tests were performed by the Florida Department of Transportation to research the permeability effect in sandy soils compacted up to 95% of maximum unit weight at the optimum moisture content. Each soil sample …

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Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh Jan 2005

Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh

Electronic Theses and Dissertations

Three dimensional reconstruction of large macromolecules like viruses at resolutions below 8 Ã… - 10 Ã… requires a large set of projection images and the particle identification step becomes a bottleneck. Several automatic and semi-automatic particle detection algorithms have been developed along the years. We present a general technique designed to automatically identify the projection images of particles. The method utilizes Markov random field modelling of the projected images and involves a preprocessing of electron micrographs followed by image segmentation and post processing for boxing of the particle projections. Due to the typically extensive computational requirements for extracting hundreds of …

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Multizoom Activity Recognition Using Machine Learning, Raymond Smith Jan 2005

Multizoom Activity Recognition Using Machine Learning, Raymond Smith

Electronic Theses and Dissertations

In this thesis we present a system for detection of events in video. First a multiview approach to automatically detect and track heads and hands in a scene is described. Then, by making use of epipolar, spatial, trajectory, and appearance constraints, objects are labeled consistently across cameras (zooms). Finally, we demonstrate a new machine learning paradigm, TemporalBoost, that can recognize events in video. One aspect of any machine learning algorithm is in the feature set used. The approach taken here is to build a large set of activity features, though TemporalBoost itself is able to work with any feature set …

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Rr Interval Estimation From An Ecg Using A Linear Discrete Kalman Filter, Arun Janapala Jan 2005

Rr Interval Estimation From An Ecg Using A Linear Discrete Kalman Filter, Arun Janapala

Electronic Theses and Dissertations

An electrocardiogram (ECG) is used to monitor the activity of the heart. The human heart beats seventy times on an average per minute. The rate at which a human heart beats can exhibit a periodic variation. This is known as heart rate variability (HRV). Heart rate variability is an important measurement that can predict the survival after a heart attack. Studies have shown that reduced HRV predicts sudden death in patients with Myocardial Infarction (MI). The time interval between each beat is called an RR interval, where the heart rate is given by the reciprocal of the RR interval expressed …

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Oceanic Rain Identification Using Multifractal Analysis Of Quikscat Sigma-0, Vasud Ganesh Torsekar Jan 2005

Oceanic Rain Identification Using Multifractal Analysis Of Quikscat Sigma-0, Vasud Ganesh Torsekar

Electronic Theses and Dissertations

The presence of rain over oceans interferes with the measurement of sea surface wind speed and direction from the Sea Winds scatterometer and as a result wind measurements contain biases in rain regions. In past research at the Central Florida Remote Sensing Lab, it has been observed that rain has multi-fractal behavior. In this report we present an algorithm to detect the presence of rain so that rain regions are flagged. The forward and aft views of the horizontal polarization σ0 are used for the extraction of textural information with the help of multi-fractals. A single negated multi-fractal exponent is …

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New Optimal High Efficiency Dsp-Based Digital Controller Design For Super High-Speed Permanent Magnet Synchronous Motor, Limei Zhao Jan 2005

New Optimal High Efficiency Dsp-Based Digital Controller Design For Super High-Speed Permanent Magnet Synchronous Motor, Limei Zhao

Electronic Theses and Dissertations

This dissertation investigates digital controller and switch mode power supply design for super high-speed permanent magnet synchronous motors (PMSM). The PMSMs are a key component for the miniaturic cryocooler that is currently under development at the University of Central Florida with support from NASA Kennedy Space Center and the Florida Solar Energy Center. Advanced motor design methods, control strategies, and rapid progress in semiconductor technology enables production of a highly efficient digital controller. However, there are still challenges for such super high-speed controller design because of its stability, high-speed, variable speed operation, and required efficiency over a wide speed range. …

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Infrared Thermography And High Accuracy Gps For Automated Asphalt Crack Detection, Tarek M. Abdel-Monem Jan 2005

Infrared Thermography And High Accuracy Gps For Automated Asphalt Crack Detection, Tarek M. Abdel-Monem

Electronic Theses and Dissertations

Roads are major public assets. The USA spends billions of dollars each year on road construction and maintenance. To keep these roads in a healthy condition and for better planning and allocation of maintenance budgets, knowledge of distressed locations is needed. Roads develop cracks when they are subjected to stresses that exceed their designed criteria or their materials properties. Early detection and repair of cracks has proven to be the most cost-effective strategy in limiting the damage to roads and reducing expenditures. Various methodologies of crack detection were developed and significant techniques were made in the last few years. One …

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Coherence Properties Of Optical Near-Fields, Debbie Arthur Jan 2005

Coherence Properties Of Optical Near-Fields, Debbie Arthur

Electronic Theses and Dissertations

The National Science Education Standards (1996) support inquiry-based instruction. According to the National Science Education Standards. When children or scientists inquire into the natural world they: ask questions, plan investigations and collect relevant data, and organize and analyze collected data. The purpose of this study was to investigate the effects of inquiry-based instruction on third-grade students' attitudes and participation in an elementary science classroom. Students were encouraged to ask and answer their own questions. In this study, analysis of data gathered form: pre and post survey, student journals, teacher field notes, and student interviews were triangulated to provide the support …

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The Effects Of Electrode Geometry On Current Pulse Caused By Electrical Discharge Over An Ultra-Fast Laser Filament, Matthew Bubelnik Jan 2005

The Effects Of Electrode Geometry On Current Pulse Caused By Electrical Discharge Over An Ultra-Fast Laser Filament, Matthew Bubelnik

Electronic Theses and Dissertations

The time-resolved electrical conductivity of a short-pulse generated plasma filament in air was studied. Close-coupled metal electrodes were used to discharge the stored energy of a high-voltage capacitor and the resulting microsecond-scale electrical discharge was measured using fast current sensors. Significant differences in the time dependence of the current were seen with the two electrode geometries used. Using sharp-tipped electrodes additional peaks in the time-resolved conductivity were seen, relative to the single peak seen with spherical electrodes. We attribute these additional features to secondary electron collisional ionization brought about by field enhancement at the tips. Additional discrepancies in the currents …

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An Introduction To Hellmann-Feynman Theory, David Wallace Jan 2005

An Introduction To Hellmann-Feynman Theory, David Wallace

Electronic Theses and Dissertations

The Hellmann-Feynman theorem is presented together with certain allied theorems. The origin of the Hellmann-Feynman theorem in quantum physical chemistry is described. The theorem is stated with proof and with discussion of applicability and reliability. Some adaptations of the theorem to the study of the variation of zeros of special functions and orthogonal polynomials are surveyed. Possible extensions are discussed.

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Classroom Observations Of Attention-Deficit/Hyperactivity Disorder: Patterns And Characteristics Of Attention Over Time, Thomas M. Timko Jr. Jan 2005

Classroom Observations Of Attention-Deficit/Hyperactivity Disorder: Patterns And Characteristics Of Attention Over Time, Thomas M. Timko Jr.

Electronic Theses and Dissertations

Investigated differences in attentional processes between children diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD) and their classroom peers. Models of attention gleaned from laboratory experiments provided a theoretical structure for hypothesizing between-group attentional differences. Seventy-five children with ADHD and 36 normal control children were observed in their regular classrooms over a 1-week time interval. Explication of between-group differences revealed that children with ADHD were approximately 21% less attentive on average. Both groups exhibited an accelerating-decelerating pattern of attention over time, however, children with ADHD cycled at a rate twice that of same-aged peers. Six variables derived from observed attention were examined for …

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A New Hybrid Diffractive Photo-Mask Technology, Jin Won Sung Jan 2005

A New Hybrid Diffractive Photo-Mask Technology, Jin Won Sung

Electronic Theses and Dissertations

In the field of photolithography for micro-chip manufacturing, the photo-mask is used to print desired patterns on a proper photo-resist on wafer. The most common type of photo-mask is binary amplitude mask made an opaque layer of chrome. The principle and potential application of hybrid photo-mask with diffractive phase element and binary amplitude is presented in this dissertation paper from both numerical modeling and experimental research. The first important application is the characterization of aberration in the stepper system using hybrid diffractive photo-mask. By utilizing multiple diffractive illumination conditions, it is possible to characterize Zernike wave front aberration coefficients up …

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The Influence Of Past Abuse On Heterosexual Cohabiting Couples' Relationship Types, Page Thanasiu Jan 2005

The Influence Of Past Abuse On Heterosexual Cohabiting Couples' Relationship Types, Page Thanasiu

Electronic Theses and Dissertations

This study investigated the influence of past witnessed or experienced abuse on heterosexual cohabiting couples' Premarital Personal and Relationship Evaluation for Cohabiting Couples (PREPARE-CC) couple relationship types. The researcher utilized preexisting data from 5,000 cohabiting couples who had previously participated in the PREPARE marriage preparation program and had completed the PREPARE-CC inventory including a demographic section that elicited information about past abuse. Discriminant analysis was conducted in SPSS to answer the question of whether the presence of past witnessed or experienced abuse could successfully predict relationship type among cohabiting couples. Results of the discriminant analysis yielded no significant ability to …

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Integrating Journal Writing With Inquiry Based Science Instruction In A Second Grade Classroom, Lauren Zissman Jan 2005

Integrating Journal Writing With Inquiry Based Science Instruction In A Second Grade Classroom, Lauren Zissman

Electronic Theses and Dissertations

This action research study investigated the effects of using science journals to promote science writing and to investigate changes in student attitudes in a second grade inquiry-based science class. This was an action research study in which qualitative and quantitative data was collected. The data was collected using science journals, pre and post inventories, field notes, teacher observations, videotaped science inquiry lessons, and surveys. The students demonstrated a true fondness for journal writing and expressed interest in continued use. After concluding this action research study, I better understand the benefits of utilizing journal writing to enhance my teaching of the …

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Simulation Studies Of Self-Assembly And Phase Diagram Of Amphiphilic Molecules, Geuorgui Kostadinov Bourov Jan 2005

Simulation Studies Of Self-Assembly And Phase Diagram Of Amphiphilic Molecules, Geuorgui Kostadinov Bourov

Electronic Theses and Dissertations

The aim of this dissertation is to investigate self-assembled structures and the phase diagram of amphiphilic molecules of diverse geometric shapes using a number of different computer simulation methods. The semi-realistic coarse-grained model, used extensively for simulation of polymers and surfactant molecules, is adopted in an off-lattice approach to study how the geometric structure of amphiphiles affects the aggregation properties. The results of simulations show that the model system behavior is consistent with theoretical predictions, experiments and lattice simulation models. We demonstrate that by modifying the geometry of the molecules, self-assembled aggregates are altered in a way close to theoretical …

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Academic Achievement Of Hispanic Students In Orange County Public High Schools:Do Hispanic Students Have Varying Degrees Of Academic Success Based On The High School They Attend?, Lawrence Marc Fox Jan 2005

Academic Achievement Of Hispanic Students In Orange County Public High Schools:Do Hispanic Students Have Varying Degrees Of Academic Success Based On The High School They Attend?, Lawrence Marc Fox

Electronic Theses and Dissertations

This study examined academic achievement levels of Hispanic high school students. Seven high schools in Orange County Public Schools in Orlando, Florida were selected. The schools were selected based on socio-economic status and demographics to provide a wide range of participation. The following are some of the purposes that guided this study: (a) to determine if there are differences in academic achievement among Hispanic high school students in each school, (b) to determine differences in academic achievement based on gender, (c) to determine differences in academic achievement based on LEP status, and (d) to determine if there is a relationship …

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How Does The Use Of Picture Books During Instruction Improve Student Word Choice In Writing?, Laurie Anne Mcadams Jan 2005

How Does The Use Of Picture Books During Instruction Improve Student Word Choice In Writing?, Laurie Anne Mcadams

Electronic Theses and Dissertations

The purpose of my research was to determine how the use of picture books during instruction would improve student word choice in writing. Donald Graves (2003), a renowned researcher in the teaching of writing, states, "All children need . . . to be surrounded with poetry, stories, information books, biography, science and history, imaginative and factual books." Graves' research presents successful classroom instruction when teachers incorporate literature as a fundamental part of their reading and writing instruction. Likewise, Susan Anderson McElveen and Connie Campbell Dierking (2000) conducted a study with their students using picture books as "precise examples" to teach …

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Spectral Signature Modification By Application Of Infrared Frequency-Selective Surfaces, Brian Monacelli Jan 2005

Spectral Signature Modification By Application Of Infrared Frequency-Selective Surfaces, Brian Monacelli

Electronic Theses and Dissertations

It is desirable to modify the spectral signature of a surface, particularly in the infrared (IR) region of the electromagnetic spectrum. To alter the surface signature in the IR, two methods are investigated: thin film application and antenna array application. The former approach is a common and straightforward incorporation of optically-thin film coatings on the surface designated for signature modification. The latter technique requires the complex design of a periodic array of passive microantenna elements to cover the surface in order to modify its signature. This technology is known as frequency selective surface (FSS) technology and is established in the …

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Supplemental Instruction In A Community College Developmental Mathematics Curriculum: A Phenomenological Study Of Learning Experiences, Julie Meer Phelps Jan 2005

Supplemental Instruction In A Community College Developmental Mathematics Curriculum: A Phenomenological Study Of Learning Experiences, Julie Meer Phelps

Electronic Theses and Dissertations

Mirroring the changing demographics of the nation, the community college student population continues to grow in size and in diversity. Almost half of all students who enter these institutions need at least one remedial course, which is often developmental mathematics. Developed in 1973, Supplemental Instruction (SI) has quickly gained recognition as an academic support program that is used to aid student performance, retention, and academic success. This dissertation used a phenomenological approach to identify factors that motivated students' attendance and subsequent learning experiences in SI sessions associated with developmental mathematics. Sources of data included five rounds of interviews (three with …

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The Effects Of Discourse And Journal Writing On Students' Attitudes Towards Mathematics In A Fifth Grade Classroom: An Action Research Study, Anna Rose Jan 2005

The Effects Of Discourse And Journal Writing On Students' Attitudes Towards Mathematics In A Fifth Grade Classroom: An Action Research Study, Anna Rose

Electronic Theses and Dissertations

The purpose of this study was to investigate how my use of discourse and journal writing affected students' attitudes and conceptions of mathematics in a 5th grade mathematics classroom. The nature of students' strengths and weaknesses with mathematics using discourse and journal writing were described. To show students' attitudes towards the two teaching methods transcription of teacher and student discourse on digital audio recordings, observational notes, journal writing, and pre and post attitude surveys were used. The research approach was qualitative and quantitative. The participants in this twelve-week study were twenty fifth grade students from a private school in central …

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Affective Design In Technical Communication, Michael Alan Rosen Jan 2005

Affective Design In Technical Communication, Michael Alan Rosen

Electronic Theses and Dissertations

Traditional human-computer interaction (HCI) is based on 'cold' models of user cognition; that is, models of users as purely rational beings based on the information processing metaphor; however, an emerging perspective suggests that for the field of HCI to mature, its practitioners must adopt models of users that consider broader human needs and capabilities. Affective design is an umbrella term for research and practice being conducted in diverse domains, all with the common thread of integrating emotional aspects of use into the creation of information products. This thesis provides a review of the current state of the art in affective …

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An Investigation Of High School Geometry Students Proving And Logical Thinking Abilities And The Impact Of Dynamic Geometry Software On Student Performance, Lalitha Subramanian Jan 2005

An Investigation Of High School Geometry Students Proving And Logical Thinking Abilities And The Impact Of Dynamic Geometry Software On Student Performance, Lalitha Subramanian

Electronic Theses and Dissertations

The purpose of this study was to investigate (a) the role of a yearlong geometry course on high school geometry students' logical thinking and proof construction abilities, (b) the linkage between students' logical thinking and proof construction abilities, and (c) the impact of dynamic geometry software on students' performance. In addition, this study also ventured to determine if the type of geometry course had any impact on students' logical thinking and proof construction achievement. The sample for the study consisted of 1,325 high school geometry students enrolled in regular, honors, and mastery courses in four high schools from the school …

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Inclusion Of Students With Disabilities: An International Perspective, Jeanette Amayo Jan 2005

Inclusion Of Students With Disabilities: An International Perspective, Jeanette Amayo

Electronic Theses and Dissertations

The purpose of this study was to examine the inclusion of students worldwide. Because the language barrier would impede the gathering of the necessary research, this study was delimited to only those English-speaking countries such as the United Kingdom, Canada, Australia, New Zealand, and the United States. The researcher examined many aspects of the education of students with disabilities in each country and how that attributed to the extent in which students with disabilities were being educated in the regular classroom. First, the researcher analyzed the legislation regarding students with disabilities, especially those directives that called for the Inclusion of …

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The Effects Of A Project-Based Mathematics Curriculum On Middle School Students' Intended Career Paths Related To Science, Technology, Engineering And Mathematics, Barbara Clanton Jan 2005

The Effects Of A Project-Based Mathematics Curriculum On Middle School Students' Intended Career Paths Related To Science, Technology, Engineering And Mathematics, Barbara Clanton

Electronic Theses and Dissertations

This study is an examination of whether a project-based mathematics curriculum would influence students' intended career paths related to science, technology, engineering, and mathematics (STEM) endeavors; perceived usefulness of mathematics; and perceived competence in doing mathematics. A review of the literature revealed that there are many shortages of professionals in STEM fields. United States women and men are not pursuing STEM endeavors in great numbers and the U.S. relies heavily on international students to fill this gap. The literature revealed that the girls who do not pursue STEM endeavors in great numbers do not perceive mathematics as a useful endeavor …

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A Dialectical Methodology For Decision Support Systems Design, Wafa Elgarah Jan 2005

A Dialectical Methodology For Decision Support Systems Design, Wafa Elgarah

Electronic Theses and Dissertations

As organizations continue to grow in size, reaching global proportions, they have ever increasing impacts on their environments. Some believe that a much broader array of concerns should be brought into organizational decision-making processes, including greater consideration of social, political, ethical and aesthetic factors (Mitroff and Linstone, 1993; Courtney, 2001). Decision environments such as these are decidedly "wicked" (Rittel and Webber, 1973). Designing decision support systems in such environments where there is a high level of interconnectedness, issues are overlapping and a multiplicity of stakeholders is involved, is a very complex task. In this dissertation a methodology for the development …

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Assessment And In Vitro Repair Of Damaged Dna Templates From Forensic Stains, Ashley Hall Jan 2005

Assessment And In Vitro Repair Of Damaged Dna Templates From Forensic Stains, Ashley Hall

Electronic Theses and Dissertations

DNA extracted from biological stains is often intractable to analysis. This may due to a number of factors including a low copy number (LCN) of starting molecules, the presence of soluble inhibitors or damaged DNA templates. Remedies may be available to the forensic scientist to deal with LCN templates and soluble inhibitors but none presently exist for damaged DNA. In fact, only recently has the biochemical nature, the extent of DNA damage in physiological stains and the point at which the damage inflicted upon a particular sample precludes the ability to obtain a genetic profile for purposes of identification been …

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