Digital Commons Network^™

Design, Calibration, And Evaluation Of Depth-Of-Interaction-Capable Pet Detector Modules, Chad J. Bircher

Dissertations and Theses (Open Access)

High-resolution, small-bore PET systems suffer from a tradeoff between system sensitivity, and image quality degradation. In these systems long crystals allow mispositioning of the line of response due to parallax error and this mispositioning causes resolution blurring, but long crystals are necessary for high system sensitivity. One means to allow long crystals without introducing parallax errors is to determine the depth of interaction (DOI) of the gamma ray interaction within the detector module. While DOI has been investigated previously, newly available solid state photomultipliers (SSPMs) well-suited to PET applications and allow new modules for investigation. Depth of interaction in full …

Exploring The Impact Of Decreased Ampk Pathway Activity On Brain Injury Outcome, Julia L. Hill

Dissertations and Theses (Open Access)

Each year, 150 million people sustain a Traumatic Brain Injury (TBI). TBI results in life-long cognitive impairments for many survivors. One observed pathological alteration following TBI are changes in glucose metabolism. Altered glucose uptake occurs in the periphery as well as in the nervous system, with an acute increase in glucose uptake, followed by a prolonged metabolic suppression. Chronic, persistent suppression of brain glucose uptake occurs in TBI patients experiencing memory loss. Abberant post-injury activation of energy-sensing signaling cascades could result in perturbed cellular metabolism. AMP-activated kinase (AMPK) is a kinase that senses low ATP levels, and promotes efficient cell …

Characterization Of A Novel Role For The To Usled- Like Kinase In Kinetochore Assembly And Function In Caenorhabditis Elegans, Jessica M. De Orbeta

Dissertations and Theses (Open Access)

Chromosome segregation is a critical step during cell division to avoid aneuploidy and promote proper organismal development. Correct sister chromatid positioning and separation during mitosis helps to achieve faithful transmission of genetic material to daughter cells. This prevents improper chromosome partitioning that can potentially result in extrachromosomal fragments, increasing the tumorigenic potential of the cells. The kinetochore is a protenaicious structure responsible for the initiation and orchestration of chromosome movement during mitosis. This highly conserved structure among eukaryotes is required for chromosome attachment to the mitotic spindle and failure to assemble the kinetochore results in aberrant chromosome segregation. Thus elucidating …

Evaluation Of Polymer Gel Dosimeters For Measurements Of Dose And Let In Proton Beams, Kevin M. Vredevoogd

Dissertations and Theses (Open Access)

This project assessed the effectiveness of polymer gel dosimeters as tools for measuring the dose deposited by and LET of a proton beam. A total of three BANG® dosimeter formulations were evaluated: BANG®-3-Pro-2 BANGkits™ for dose measurement and two BANG®-3 variants, the LET-Baseline and LET-Meter dosimeters, for LET measurement. All dosimeters were read out using an OCT scanner. The basic characteristics of the BANGkits™ were assessed in a series of photon and electron irradiations. The dose-response relationship was found to be sigmoidal with a threshold for response of approximately 15 cGy. The active region of the dosimeter, the volume in …

Characterization Of Selective Inhibition Of Adenylyl Cyclase Activity By Small Molecule Inhibitor Nky80, Cameron S. Brand

Dissertations and Theses (Open Access)

The nine membrane-bound isoforms of adenylyl cyclase (AC), via synthesis of the signaling molecule cyclic AMP (cAMP), are involved in many isoform specific physiological functions. Decreasing AC5 activity has been shown to have potential therapeutic benefit, including reduced stress on the heart, pain relief, and attenuation of morphine dependence and withdrawal behaviors. However, AC structure is well conserved, and there are currently no isoform selective AC inhibitors in clinical use.

P-site inhibitors inhibit AC directly at the catalytic site, but with an uncompetitive or noncompetitive mechanism. Due to this mechanism and nanomolar potency in cell-free systems, attempts at ligand-based drug …

Development Of A Beam-Specific Planning Target Volume And A Robust Plan Analysis To Ol For Proton Therapy, Peter Park

Dissertations and Theses (Open Access)

Proton therapy is growing increasingly popular due to its superior dose characteristics compared to conventional photon therapy. Protons travel a finite range in the patient body and stop, thereby delivering no dose beyond their range. However, because the range of a proton beam is heavily dependent on the tissue density along its beam path, uncertainties in patient setup position and inherent range calculation can degrade thedose distribution significantly. Despite these challenges that are unique to proton therapy, current management of the uncertainties during treatment planning of proton therapy has been similar to that of conventional photon therapy. The goal of …

A Unified Picture Of Breaks And Truncations In Spiral Galaxies From Sdss And S4g Imaging., Ignacio Martin-Navarro, Judit Bakos, Ignacio Trujillo, Johan H. Knapen, E. Athanassoula, A. Bosma, Sebastien Comeron, Bruce G. Elmegreen, Santiago Erroz-Ferrer, Dimitri A. Gadotti, Armando Gil De Paz, Joannah L. Hinz, Luis C. Ho, Benne W. Holwerda, Taehyun Kim, Jarkko Laine, Eija Laurikainen, Karin Menendez-Delmestre, Trisha Mizusawa, Juan Carlos Munoz-Mateos, Michael W. Regan, Heikki Salo, Mark Seibert, Kartik Sheth

Faculty and Staff Scholarship

The mechanism causing breaks in the radial surface-brightness distribution of spiral galaxies is not yet well known. Despite theoretical efforts, there is not a unique explanation for these features and the observational results are not conclusive. In an attempt to address this problem, we have selected a sample of 34 highly inclined spiral galaxies present in both the Sloan Digital Sky Survey (SDSS) and the Spitzer Survey of Stellar Structure in Galaxies (S4G). We have measured the surface-brightness profiles in the five Sloan optical bands and in the 3.6-µm Spitzer band. We have also calculated the colour and stellar surface …

Perfectionism: The Good, The Bad, And The Creative, Benjamin Wigert, Roni Reiter-Palmon, James C. Kaufman, Paul J. Silvia

Psychology Faculty Publications

The influence of adaptive and maladaptive perfectionism on creativity was examined. Initially, six measures of creativity were administered, including creative self-perceptions, behavior, and performance measures. Adaptive perfectionism was weakly positively related to creativity, whereas maladaptive perfectionism was unrelated to creativity across five of the six measures. A follow-up study assessed whether initial findings could be generalized to an everyday problem-solving task. Results indicated that adaptive perfectionism was related to higher quality but not originality of solutions. Further, a curvilinear relationship in the shape of an inverted “U” occurred between adaptive perfectionism and four of eight creativity measures. Overall, adaptive perfectionism …

Neural Responses To Food Pictures And Their Association With Dietary Intake, Edward Christenson

Theses and Dissertations

BACKGROUND: Food-related visual cues may affect eating behavior and energy intake. The purpose of this study was to determine the neural response to pictures of food and whether or not the neural responses were associated with energy intake. METHODS: Using a cross-sectional design, 60 adults participated in this study. Each participant reported to the laboratory in a fasted state, were fitted with a 128-electrode electroencephalogram (EEG) net, and were shown pictures grouped into three categories: high-calorie foods, low-calorie foods, and distractor pictures. These pictures were shown in random order. Furthermore, participants were shown these pictures in one passive condition and …

Do Vcs Use Inside Rounds To Dilute Founders? Some Evidence From Silicon Valley, Brian Broughman, Jesse Fried

Vanderbilt Law School Faculty Publications

In the bank-borrower setting, a firm's existing lender may exploit its positional advantage to extract rents from the firm in subsequent financings. Analogously, a startup's existing venture capital investors (VCs) may dilute the founder through a follow-on financing from these same VCs (an “inside” round) at an artificially low valuation. Using a hand-collected dataset of Silicon Valley startup firms, we find little evidence that VCs use inside rounds to dilute founders. Instead, our findings suggest that inside rounds are generally used as “backstop financing” for startups that cannot attract new money, and these rounds are conducted at relatively high valuations …

The Incredible Shrinking Confrontation Clause, Jeffrey Bellin

Vanderbilt Law School Faculty Publications

Sharp turns in the Supreme Court's recent Confrontation Clause jurisprudence have left scholars reeling from conflicting emotions: exhilaration, despair, denial, and soon, perhaps, cynical acceptance. While most commentators celebrated the demise of the incoherent Ohio v. Roberts framework, their excitement largely faded as the Court's decisions in Davis v. Washington and Bryant v. Michigan revealed nascent flaws in the evolving doctrine and sharply curtailed the newly revitalized confrontation right.

Recent scholarship strives to reanimate the jurisprudence by expanding the doctrinal definition of "testimonial" statements - the sole form of evidence Associate Professor, William & Mary Law School. I would like …

What Is The Essential Fourth Amendment?, Christopher Slobogin

Vanderbilt Law School Faculty Publications

In More Essential Than Ever: The Fourth Amendment in the Twenty-First Century, Stephen Schulhofer provides a strong, popularized brief for interpreting the Fourth Amendment as a command that judicial review precede all non-exigent police investigative actions that are more than minimally intrusive. This review points out a few places where Schulhofer may push the envelope too far or not far enough, but concludes that More Essential Than Ever is a welcome reminder for scholars and the public at large that the Fourth Amendment is a fundamental bulwark of constitutional jurisprudence and deserves more respect than the Supreme Court has given …

Can The States Keep Secrets From The Federal Government?, Robert A. Mikos

Vanderbilt Law School Faculty Publications

States amass troves of information detailing the regulated activities of their citizens, including activities that violate federal law. Not surprisingly, the federal government is keenly interested in this information. It has ordered reluctant state officials to turn over their confidential files concerning medical marijuana, juvenile criminal history, immigration status, tax payments, and employment discrimination, among many other matters, to help enforce federal laws against private citizens. Many states have objected to these demands, citing opposition to federal policies and concerns about the costs of breaching confidences, but the lower courts have uniformly upheld the federal government’s power to commandeer information …

مدخل محاسبي لجدوى المشاريع الاستثمارية دراسة تطبيقية في مدرسة أوروك الابتدائية الأهلية, محمد محمود جاسم الطائــي

Muthanna Journal of Administrative and Economics Sciences

تسعى هذه الدراسة لتحقيق هدفين رئيسين ، فأما الأول فأنه يتمثل بتسليط الضوء على دراسات الجدوى وماهية القرار الاستثماري العقلاني في قطاع من القطاعات الاستثمارية والذي يحتاج إلى درجة من الاطمئنان على رأس المال المستثمر ، إذ تعد تلك الدراسات والتي تسبق ذلك القرار من الأمور المهمة والعلمية والعملية لصحة اتخاذ ذلك القرار من عدمه ، إذ إن تلك الدراسات إذا ما أعدت وفقاً لأسس صحيحة بتعددها وتنوعها كجوانبها الفنية والتسويقية والمالية وغيرها تتسم بالتكامل . والهدف الثاني يتمثل بتوضيح العلاقة بين دراسات الجدوى والقرارات الاستثمارية ، إذ كلما كانت تلك الدراسات صحيحة وجدية كلما كانت عملية اتخاذ القرار الاستثماري …

Plea Bargaining And The Right To The Effective Assistance Of Counsel: Where The Rubber Hits The Road In Capital Cases, John H. Blume

Cornell Law Faculty Publications

No abstract provided.

Measuring Learning Through Cross Sectional Testing, Steve Lovett, Jennie Johnson

Management Faculty Publications

The measurement of student learning is becoming increasingly important in U.S. higher education. One way to measure learning is through longitudinal testing, but this becomes especially difficult when applied to cumulative learning within programs in situations of low persistence. In particular, many Hispanic Serving Institutions (HSIs) find themselves in such situations. Cross sectional testing is a pragmatic alternative, so long as maturity and selection effects can be estimated. The purpose of this paper is to demonstrate the utility and mechanics of measuring learning through cross sectional testing.

An Inquiry Approach To Reading Instruction: A Case Study Of The Relationship Between Instruction And Motivation, Tammy Turri-Scodeller

Dissertations

This research is a qualitative case study analysis of the experiences of five fifth grade students who were involved in a classroom, action research project. The purpose of this action research was to measure the impact of this method of instruction on reading motivation of the fifth grade class as a whole. From the action research project, five, individual, student cases were purposefully sampled for further in-depth analysis. The objective of the individual student case study analysis was to explain how the behaviors of five students with a low level of reading achievement, activity, and motivation changed, or did not …

From Crisis To Stability: A Case Study Of Presidential Leadership At A Christian College, Jeffrey Gill

Dissertations

Despite healthy growth in past decades, in a time of national and global economic instability small, private Christian colleges now find themselves in a precarious position. Leading effectively in such colleges and universities in a time of external and/or internal crisis is a great challenge.

This research is about a small, Christian college with documented evidence of having survived two significant enrollment and financial crises (early 1990s and 2008-09), and is now stable, all under the leadership of a president who served during the 19 year time period of crisis and stability. The purpose of this study is to investigate …

Analysis Of Genotype, Phenotype, And Age Progression In Phelan-Mcdermid Syndrome, Sara Sarasua

All Dissertations

Phelan-McDermid syndrome is a developmental disability syndrome associated with deletions of the terminal end of one copy of chromosome 22q13. The observed chromosomal aberrations include simple terminal deletions, interstitial deletions, deletions and duplications, and duplications without deletions. All patients have some degree of developmental disability and many also have hypotonia, autism, minor dysmorphic features, and seizures. I performed an epidemiological and cytogenetic investigation to better understand the etiology of Phelan-McDermid syndrome and to provide information to patients and their families, clinicians, and researchers investigating developmental disabilities. Deletions vary widely in size, from 60 kb to more than 9 Mb, but …

The Effects Of 0.2 Hz Varying Latency With 20-100 Ms Varying Amplitude On Simulator Sickness In A Helmet Mounted Display, Matthew St. Pierre

All Dissertations

The relationship between the occurrence of simulator sickness (SS) and the several characteristics of latency (i.e., added latency, amplitude of latency, and frequency of latency) in a helmet-mounted display (HMD) were explored in this study. The experience of SS while using an HMD has often been attributed to system latency. These findings are typical in research where HMDs with head trackers are used. The current study explored the effects of 200 ms added constant latency, latency varying at 0.2 Hz with a constant 100 ms amplitude, and latency varying at 0.2 Hz with a 20-100 ms varying amplitude on the …

Assessing The National Innovation System In A Developing Country Context: A Framework And Evidence From Thailand, Maleena Parkey

All Dissertations

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Asymptotics For The Arc Length Of A Multivariate Time Series And Its Applications As A Measure Of Risk, Tharanga Wickramarachchi

All Dissertations

The necessity of more trustworthy methods for measuring the risk (volatility) of financial assets has come to the surface with the global market downturn This dissertation aims to propose sample arc length of a time series, which provides a measure of the overall magnitude of the one-step-ahead changes over the observation time period, as a new approach for quantifying the risk. The Gaussian functional central limit theorem is proven under finite second moment conditions. Without loss of generality we consider equally spaced time series when first differences of the series follow a variety of popular stationary models including autoregressive moving …

Molecular Genetics Of Nodule Number Regulation: Cloning, Characterization And Functional Studies Of The Root Determined Nodulator1 (Rdn1) Gene In Medicago Truncatula, Tessema Kassaw

All Dissertations

Nitrogen is critical to life. However, the majority of nitrogen on earth (in the atmosphere) is inert and unavailable to nearly all organisms. Metabolically diverse prokaryotes are the only organisms capable of fixing atmospheric nitrogen; rhizobia set up a symbiosis with legume plants allowing the plants to benefit from this ability. Since nodulation and the subsequent nitrogen fixation processes are energy intensive, the host plant must balance hosting of the rhizobia by limiting the number of nodules it forms through a mechanism called Autoregulation of Nodulation (AON). My study of mutants in the model legume Medicago truncatula defective in AON …

Assessment Of Fidelity To Data And Robustness To Uncertainty To Assure Credible Predictions In The Modeling Of Wind Turbine Blades, Kendra Van Buren

All Dissertations

In the field of wind energy, modeling and simulation techniques provide an efficient and economical alternative to experimentation for studying the behavior of wind turbines. Numerical models however are approximations of reality, thusly making it crucial to evaluate various sources of uncertainties that influence the model predictions. Credibility of a numerical model rests on the model's ability to replicate existing experimental data, widely known as fidelity-to-data. This dissertation advocates that fidelity-to-data, while necessary, is insufficient to claim credibility of a numerical model. Herein, the objective is to develop numerical models that not only provide agreement to experimental data, but also …

Phase Transformation In Ti-Mo-O, Herbert Boeckels

All Dissertations

The present dissertation has investigated the effect of oxygen on the ù and á phase stability in metastable Ti-Mo â titanium alloys using thermal analysis, hardness measurements, electron microscopy, and x-ray diffraction.
Single crystal x-ray diffraction has shown that oxygen atoms are located in the tetrahedral interstitial lattice sites in the rapidly cooled bcc Ti crystal structure, interfering directly with the reversible displacive formation of ù, with this transformation involving collapse of the bcc lattice along â. Subsequent thermal exposure of reversible ù, as occurring during slower cooling, heating, and aging, prompts short range diffusion and the formation of chemical …

Network Traffic Analysis Using Stochastic Grammars, Chen Lu

All Dissertations

Network traffic analysis is widely used to infer information from Internet
traffic. This is possible even if the traffic is encrypted. Previous work uses
traffic characteristics, such as port numbers, packet sizes, and frequency,
without looking for more subtle patterns in the network traffic. In this work,
we use stochastic grammars, hidden Markov models (HMMs) and probabilistic
context-free grammars (PCFGs), as pattern recognition tools for traffic
analysis.
HMMs are widely used for pattern recognition and detection. We use a HMM
inference approach. With inferred HMMs, we use confidence intervals (CI) to
detect if a data sequence matches the HMM. To …

Policy Evaluation Using Cost-Benefit Analysis: Empirical Ramifications For Two Policy Issues, Elizabeth Crouch

All Dissertations

Using two distinct health policy issues my research examines the relevance and ramifications of using cost-benefit analysis (CBA) to demonstrate real-world impacts of the policies. My dissertation discusses how these two situations represent particular challenges to cost-benefit analysis. The challenges have specific implications for how scholars, agencies, and government entities should use CBA to evaluate policies. Specifically, my research finds that by separating CBA into four different approaches, a much more complete, and less assumption-laden, CBA can be accomplished.

Coaching Equestrian Vaulting: The Motivation Behind Volunteer Coaching, Amy Mccune

All Dissertations

The purpose of this research was to identify the primary motivations for people to become and continue as equestrian vaulting coaches. Using a nomothetic context for research, this study focused on gaining a better understanding of equestrian vaulting coaches by identifying factors that generally motivate their participation in the sport. The first research question related to what motivates someone to become a vaulting coach while the second question related to what motivates these coaches to continue in the coaching role.
Fifteen female coaches were selected for interviews from the American Vaulting Association membership. Interview questions were based on a preliminary …

Understanding The Relative Attentional Demands Of The Dimensions Of Interface Consistency, Jeremy Mendel

All Dissertations

A consistent interface is thought to be beneficial because it allows users to draw on previous training and experience when operating a new interface. Design guidelines like the eight golden rules of interface design argue that a highly consistent interface improves system usability (Shneiderman, 1987). However, interface consistency is not monolithic; instead it is a complex, multidimensional construct. I refer to the two dimensions of interface consistency as perceptual consistency (the appearance) and conceptual consistency (the functionality) of an interface. Perceptual consistency considers aspects like interface layout and orientation; conceptual consistency considers how the system operates or responds. I sought …

The Contribution Of Poly(Adp-Ribose)Polymerase-1 Activity In The Nucleotide Excision Repair Pathway, Brenee S. King

Biomedical Sciences ETDs

Exposure to ultraviolet radiation (UVR) promotes the formation of UVR-induced, DNA helix distorting photolesions such as (6-4) pyrimidine-pyrimidone photoproducts (6-4 PPs) and cyclobutane pyrimidine dimers (CPDs). Effective repair of such lesions by the nucleotide excision repair (NER) pathway is required to prevent DNA mutations and chromosome aberrations. Poly(ADP-ribose)polymerase-1 (PARP-1) is a zinc-finger protein with well documented involvement in base excision repair (BER). PARP-1 is activated in response to DNA damage and catalyzes the formation of poly(ADP-ribose) subunits (PAR) that assist in the assembly of DNA repair complexes at sites of damage. In this dissertation, I present evidence for PARP-1 contributions …