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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

A Funny Thing Happened on the Way to My Ph.D.: Exploring Issues Affecting Attrition and Completion in the Doctoral Program in Instructional Technology at a Major Research University

Williams, Carla L 20 December 2012 (has links)
This study sought to understand why some students at Eagle University (pseudo.) complete the doctoral program in instructional technology while others do not. The study explores factors and issues affecting doctoral attrition and completion of the Ph.D. in instructional technology (IT) in the College of Education at Eagle University, a major research university with very high research activity. Participants in the study were eleven former doctoral students from Eagle University (pseudo.), six of whom met the requirements for graduation (completers) and five of whom ended the pursuit of the doctoral degree in instructional technology at EU (non-completers). A qualitative study informed by phenomenology, the purpose of the study was to explore these phenomena from the perspective of the students. Postmodernism served as the theoretical framework. Participants were interviewed using the structured interview guide developed by the researcher. Two important findings were that only one of the eleven students knew what to expect from the program; and that completers were more likely to report that their primary motivation for pursuing the Ph.D. was for personal satisfaction. Recommendations were made based on student feedback, and included implications for students as well as implications for the university/program. Examples of advice for students were: 1) contemplate their goal(s) in pursuing the Ph.D. and consider the impact if something happened to alter that goal, and 2) seek out doctoral support groups and begin to establish relationships with current members. Two selected recommendations for the university/program were 1) develop a pre-application seminar or eLearning module to provide potential doctoral students with a realistic understanding of the program, and 2) consider developing a mentoring program that matched more experienced students or non-advisory professors to new students. Results of the study indicated that multiple factors affected both completers and non-completers; and these factors were often similar. However, among the key factors separating completers from non-completers were the determination of the student and the quality of the advisor relationship.
52

Cardiac and fibroblastic properties after HIF-1α stabilization / Cardiac and fibroblastic properties after HIF-1α stabilization

Vogler, Melanie 21 May 2015 (has links)
No description available.
53

A Funny Thing Happened on the Way to My Ph.D.: Exploring Issues Affecting Attrition and Completion in the Doctoral Program in Instructional Technology at a Major Research University

Williams, Carla L 20 December 2012 (has links)
This study sought to understand why some students at Eagle University (pseudo.) complete the doctoral program in instructional technology while others do not. The study explores factors and issues affecting doctoral attrition and completion of the Ph.D. in instructional technology (IT) in the College of Education at Eagle University, a major research university with very high research activity. Participants in the study were eleven former doctoral students from Eagle University (pseudo.), six of whom met the requirements for graduation (completers) and five of whom ended the pursuit of the doctoral degree in instructional technology at EU (non-completers). A qualitative study informed by phenomenology, the purpose of the study was to explore these phenomena from the perspective of the students. Postmodernism served as the theoretical framework. Participants were interviewed using the structured interview guide developed by the researcher. Two important findings were that only one of the eleven students knew what to expect from the program; and that completers were more likely to report that their primary motivation for pursuing the Ph.D. was for personal satisfaction. Recommendations were made based on student feedback, and included implications for students as well as implications for the university/program. Examples of advice for students were: 1) contemplate their goal(s) in pursuing the Ph.D. and consider the impact if something happened to alter that goal, and 2) seek out doctoral support groups and begin to establish relationships with current members. Two selected recommendations for the university/program were 1) develop a pre-application seminar or eLearning module to provide potential doctoral students with a realistic understanding of the program, and 2) consider developing a mentoring program that matched more experienced students or non-advisory professors to new students. Results of the study indicated that multiple factors affected both completers and non-completers; and these factors were often similar. However, among the key factors separating completers from non-completers were the determination of the student and the quality of the advisor relationship.
54

Protein Design Based on a PHD Scaffold

Kwan, Ann Hau Yu January 2004 (has links)
The plant homeodomain (PHD) is a protein domain of ~45�100 residues characterised by a Cys4-His-Cys3 zinc-binding motif. When we commenced our study of the PHD in 2000, it was clear that the domain was commonly found in proteins involved in transcription. Sequence alignments indicate that while the cysteines, histidine and a few other key residues are strictly conserved, the rest of the domain varies greatly in terms of both amino acid composition and length. However, no structural information was available on the PHD and little was known about its function. We were therefore interested in determining the structure of a PHD in the hope that this might shed some light on its function and molecular mechanism of action. Our work began with the structure determination of a representative PHD, Mi2b-P2, and this work is presented in Chapter 3. Through comparison of this structure with the two other PHD structures that were determined during the course of our work, it became clear that PHDs adopt a well-defined globular fold with a superimposable core region. In addition, PHDs contain two loop regions (termed L1 and L3) that display increased flexibility and overlay less well between the three PHD structures available. These L1 and L3 regions correspond to variable regions identified earlier in PHD sequence alignments, indicating that L1 and L3 are probably not crucial for the PHD fold, but are instead likely to be responsible for imparting function(s) to the PHD. Indeed, numerous recent functional studies of PHDs from different proteins have since demonstrated their ability in binding a range of other proteins. In order to ascertain whether or not L1 and L3 were in fact dispensable for folding, we made extensive mutations (including both insertions and substitutions) in the loop regions of Mi2b-P2 and showed that the structure was maintained. We then went on to illustrate that a new function could be imparted to Mi2b-P2 by inserting a five-residue CtBP-binding motif into the L1 region and showed this chimera could fold and bind CtBP. Having established that the PHD could adopt a new binding function, we next sought to use combinatorial methods to introduce other novel functions into the PHD scaffold. Phage display was selected for this purpose, because it is a well-established technique and has been used successfully to engineer zinc-binding domains by other researchers. However, in order to establish this technique in our laboratory, we first chose a control system in which two partner proteins were already known to interact in vitro. We chose the protein complex formed between the transcriptional regulators LMO2 and ldb1 as a test case. We have examined this interaction in detail in our laboratory, and determined its three-dimensional structure. Furthermore, inappropriate formation of this complex is implicated in the onset of T-cell acute lymphoblastic leukemia. We therefore sought to use phage display to engineer ldb1 mimics that could potentially compete against wild-type ldb1 for LMO2, and this work is described in Chapter 4. Using a phage library containing ~3 x 10 7 variants of the LMO2-binding region of ldb1, we isolated mutants that were able to interact with LMO2 with higher affinity and specificity than wild-type ldb1. These ldb1 mutants represent a first step towards finding potential therapeutics for treating LMO-associated diseases. Having established phage display in our laboratory, we went on to search for PHD mutants that could bind selected target proteins. This work is described in Chapter 5. We created three PHD libraries with eight randomized residues in each of L1, L3 or in both loops of the PHD. These PHD libraries were then screened against four target proteins. After four rounds of selection, we were able to isolate a PHD mutant (dubbed L13-FH6) that could bind our test protein Fli-ets. This result demonstrates that a novel function can be imparted to the PHD using combinatorial methods and opens the way for further work in applying the PHD scaffold to other protein design work. In summary, the work detailed in Chapters 3 and 5 demonstrates that the PHD possesses many of the properties that are desirable for a protein scaffold for molecular recognition, including small size, stability, and a well-characterised structure. Moreover, the PHD motif possesses two loops (L1 and L3) of substantial size that can be remodeled for target binding. This may lead to an enhancement of binding affinities and specificities over other small scaffolds that have only one variable loop. In light of the fact that PHDs are mainly found in nuclear proteins, it is reasonable to expect that engineered PHDs could be expressed and function in an intracellular environment, unlike many other scaffolds that can only function in an oxidizing environment. Therefore, our results together with other currently available genomic and functional information indicate PHD is an excellent candidate for a scaffold that could be used to modify cellular processes. Appendices 1 and 2 describe completed bodies of work on unrelated projects that I have carried out during the course of my PhD candidature. The first comprises the invention and application of DNA sequences that contain all N-base sequences in the minimum possible length. This work is presented as a reprint of our recently published paper in Nucleic Acids Research. The second Appendix describes our structural analysis of an antifreeze protein from the shorthorn sculpin, a fish that lives in the Arctic and Antarctic oceans. This work is presented as a manuscript that is currently under review at the Journal of the American Chemical Society.
55

The Value of a STEM PhD

January 2018 (has links)
abstract: The quality and quantity of talented members of the US STEM workforce has been a subject of great interest to policy and decision makers for the past 40 years. Recent research indicates that while there exist specific shortages in specific disciplines and areas of expertise in the private sector and the federal government, there is no noticeable shortage in any STEM academic discipline, but rather a surplus of PhDs vying for increasingly scarce tenure track positions. Despite the seeming availability of industry and private sector jobs, recent PhDs still struggle to find employment in those areas. I argue that the decades old narrative suggesting a shortage of STEM PhDs in the US poses a threat to the value of the natural science PhD, and that this narrative contributes significantly to why so many PhDs struggle to find career employment in their fields. This study aims to address the following question: what is the value of a STEM PhD outside academia? I begin with a critical review of existing literature, and then analyze programmatic documents for STEM PhD programs at ASU, interviews with industry employers, and an examination the public face of value for these degrees. I then uncover the nature of the value alignment, value disconnect, and value erosion in the ecosystem which produces and then employs STEM PhDs, concluding with specific areas which merit special consideration in an effort to increase the value of these degrees for all stakeholders involved. / Dissertation/Thesis / Doctoral Dissertation Science and Technology Policy 2018
56

System-Level Synthesis of Dataplane Subsystems for MPSoCs

January 2013 (has links)
abstract: In recent years we have witnessed a shift towards multi-processor system-on-chips (MPSoCs) to address the demands of embedded devices (such as cell phones, GPS devices, luxury car features, etc.). Highly optimized MPSoCs are well-suited to tackle the complex application demands desired by the end user customer. These MPSoCs incorporate a constellation of heterogeneous processing elements (PEs) (general purpose PEs and application-specific integrated circuits (ASICS)). A typical MPSoC will be composed of a application processor, such as an ARM Coretex-A9 with cache coherent memory hierarchy, and several application sub-systems. Each of these sub-systems are composed of highly optimized instruction processors, graphics/DSP processors, and custom hardware accelerators. Typically, these sub-systems utilize scratchpad memories (SPM) rather than support cache coherency. The overall architecture is an integration of the various sub-systems through a high bandwidth system-level interconnect (such as a Network-on-Chip (NoC)). The shift to MPSoCs has been fueled by three major factors: demand for high performance, the use of component libraries, and short design turn around time. As customers continue to desire more and more complex applications on their embedded devices the performance demand for these devices continues to increase. Designers have turned to using MPSoCs to address this demand. By using pre-made IP libraries designers can quickly piece together a MPSoC that will meet the application demands of the end user with minimal time spent designing new hardware. Additionally, the use of MPSoCs allows designers to generate new devices very quickly and thus reducing the time to market. In this work, a complete MPSoC synthesis design flow is presented. We first present a technique \cite{leary1_intro} to address the synthesis of the interconnect architecture (particularly Network-on-Chip (NoC)). We then address the synthesis of the memory architecture of a MPSoC sub-system \cite{leary2_intro}. Lastly, we present a co-synthesis technique to generate the functional and memory architectures simultaneously. The validity and quality of each synthesis technique is demonstrated through extensive experimentation. / Dissertation/Thesis / Ph.D. Computer Science 2013
57

A COMPARISON OF THE PROBABILITY HYPOTHESIS DENSITY FILTER AND THE MULTIPLE HYPOTHESIS TRACKER FOR TRACKING TARGETS OF MULTIPLE TYPES

Brodovsky, James A. January 2019 (has links)
Robotic technology is advancing out of the laboratory and into the everyday world. This world is less ordered than the laboratory and requires an increased ability to identify, target, and track objects of importance. The Bayes filter is the ideal algorithm for tracking a single target and there exists a significant body of work detailing tractable approximations of it with the notable examples of the Kalman and Extended Kalman filter. Multiple target tracking also relies on a similar principle and the Kalman and Extended Kalman filter have multi-target implementations as well. Other method include the PHD filter and Multiple Hypothesis tracker. One issue is that these methods were formulated to only track one classification of target. With the increased need for robust perception, there exists a need to develop a target tracking algorithm that is capable of identifying and tracking targets of multiple classifications. This thesis examines two of these methods: the Probability Hypothesis Density (PHD) filter and the Multiple Hypothesis Tracker (MHT). A Matlab-based simulation of an office floor plan is developed and a simulation UGV equipped with a camera is set the task of navigating the floor plan and identifying targets. Results of these experiments indicated that both methods are mathematically capable of achieving this. However, there was a significant reliance on post-processing to verify the performance of each algorithm and filter out noisy sensor inputs indicating that specific multi-target multi-class implementations of each algorithm should be implemented with a detailed and more accurate sensor model. / Mechanical Engineering
58

Doctoral profile of the medical radiation sciences: a baseline for Australia and New Zealand

Ekpo, E.U., Snaith, Beverly, Harris, Martine A., McEntee, M.F. 25 April 2017 (has links)
Yes / Research is critical to evidence‐based practice, and the rapid developments in technology provide opportunities to innovate and improve practice. Little is known about the research profile of the medical radiation science (MRS) profession in Australia and New Zealand (NZ). This study provides a baseline of their doctoral activity. A cross‐sectional survey of MRS professionals in Australia and NZ holding a doctorate or undertaking doctoral studies, was performed using an online tool (Bristol Online Survey®, Bristol, UK). A chain‐referral sampling technique was adopted for data collection. An email invitation with a link to the survey was generated and distributed through email and social media. The survey contained questions related to participant demographics, doctoral status, qualification route, funding and employment. There were 63 responses to the survey comprising 50.8% diagnostic radiographers (DRs; n = 32), 23.8% radiation therapists (RTs; n = 15), with the remaining 25.4% (n = 16) equally split between sonographers and nuclear medicine technologists (NMTs). A total of 40 (63.5%) of respondents had completed their doctoral qualification. In NZ, only DRs held a doctoral award constituting 0.3% of DRs and 0.2% of the total registered MRS population. In Australia, there was a greater proportion of doctoral NMTs (n = 8/1098; 0.7%) than RTs (n = 15/2394; 0.6%) and DRs (n = 27/12,001; 0.2%). Similar to other countries, findings show a very small percentage of doctoral MRS professionals in Australia and NZ. Strategies to engage and support individuals in research, up to and beyond doctoral study, need to be embedded in practice.
59

Chemoresistenz als Folge einer Inhibition der zellulären Sauerstoffsensoren (Prolyl-4-Hydroxylase-Domäne) / Increased chemoresistance induced by inhibition of HIF-prolyl-hydroxylase domain enzymes.

Brökers, Nils 13 December 2010 (has links)
No description available.
60

3rd PhD conference: The social responsibility of science and scientists

Promovierendenrat der TU Bergakademie Freiberg 30 April 2019 (has links)
This is the abstract book of the 3rd PhD conference at the TU Bergakademie Freiberg presenting the abstracts of the keynote speaker and the oral presentations.

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