Current Search: Profiling (x)
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Title
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RAINDROP SIZE DISTRIBUTION RETRIEVAL AND EVALUATION USING AN S-BAND RADAR PROFILER.
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Creator
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Fang, Fang, Jones, Linwood, University of Central Florida
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Abstract / Description
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Vertical pointing Doppler radar profilers are used to explore the vertical structure of precipitation cloud systems and to provide validation information for use in weather research. In this thesis, a theoretical radar rain-backscatter model was developed to simulate profiler Doppler spectra as a function of assumed rain parameters, of which the raindrop size distribution (DSD) is the fundamental quantity used to describe the characteristics of rain. Also, profiler observations during...
Show moreVertical pointing Doppler radar profilers are used to explore the vertical structure of precipitation cloud systems and to provide validation information for use in weather research. In this thesis, a theoretical radar rain-backscatter model was developed to simulate profiler Doppler spectra as a function of assumed rain parameters, of which the raindrop size distribution (DSD) is the fundamental quantity used to describe the characteristics of rain. Also, profiler observations during stratiform rain are analyzed to retrieve the corresponding rain DSD's. In particular, a gamma distribution model is introduced, which uses Rayleigh scattering portion of the Doppler velocity spectrum to estimate the raindrop size distribution. This theoretical scattering model was validated by simulating atmospheric profiles of precipitation Doppler spectra and three moments (reflectivity, mean Doppler velocity and spectral width) and then comparing these with the corresponding measurements from an S-band radar profiler during a NASA conducted Tropical Rainfall Measuring Mission (TRMM) field experiment in Central Florida in 1998. Also, the results of my analysis yielding precipitation retrievals are validated with an independent, simultaneous Joss-Waldvogel Disdrometer rain DSD observations that were collocated with the radar profiler.
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Date Issued
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2004
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Identifier
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CFE0000127, ucf:46190
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0000127
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Title
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A CONFIGURAL APPROACH TO PATIENT SAFETY CLIMATE: THE RELATIONSHIP BETWEEN CLIMATE PROFILE CHARACTERISTICS AND PATIENT OUTCOMES.
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Creator
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Weaver, Sallie, Salas, Eduardo, University of Central Florida
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Abstract / Description
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Patient safety climate is defined as a holistic snapshot of enacted work environment practices and procedures related to patient safety, derived from shared perceptions of social and environmental work characteristics. While patient safety climate has been touted as a critical factor underlying safe patient care, our understanding of input factors influencing shared climate perceptions and, in turn, the effects of climate as a collective, group-level construct on important outcomes remains...
Show morePatient safety climate is defined as a holistic snapshot of enacted work environment practices and procedures related to patient safety, derived from shared perceptions of social and environmental work characteristics. While patient safety climate has been touted as a critical factor underlying safe patient care, our understanding of input factors influencing shared climate perceptions and, in turn, the effects of climate as a collective, group-level construct on important outcomes remains underdeveloped, both theoretically and empirically. Therefore, the current study examines (1) the antecedents that impact individual patient safety climate perceptions and (2) the relationships between hospital unit patient safety climate and two important unit level outcomes: patient willingness to recommend a facility to others and patient safety. This study also examines climate strength-the degree to which climate perceptions are shared-as a moderator of these relationships. While climate is conceptualized as a holistic description of the working environment, existing evidence has focused on relationships between the independent dimensions of patient safety climate and patient safety. No study to date has examined the configurations (i.e. patterns or profiles) among the multiple dimensions of patient safety climate or how these configurations are related to important employee and patient outcomes. This gap is redressed in the current study by examining patient safety climate in terms of three profile characteristics: (1) climate elevation (i.e., mean positive or negative valence across all dimensions), (2) climate variability (i.e., variance among dimensions), and (3) climate shape (i.e., the pattern of peaks and valleys among climate dimensions). Evidence from studies of general organizational climate suggests that the shape of the pattern among climate dimensions, the overall mean score across dimensions, and the degree to which dimension scores vary are predictive of employee attitudes, customer satisfaction, and organizational financial performance (Dickson et al., 2006; Joyce & Slocum, 1984; Jackofsky & Slocum, 1988; Gonzalez-Roma, Peiro, & Zornoza, 1999; Litwin & Stringer, 1968; Schulte et al., 2009). The current study, then, tests a theoretical model of patient safety climate examining the configural nature of the construct. An archival dataset collected from seven hospitals located in a metropolitan area of the southeastern United States was utilized to test study hypotheses. Data was collected from 3,149 individuals nested within 84 hospital units using the Hospital Survey on Patient Safety Culture (Sorra & Nieva, 2004). Unit level patient safety and patient willingness to recommend was collected by the hospital risk management and nursing administration departments. Hierarchical linear modeling (HLM7; Raudenbush, Bryk, Cheong, Congdon, & du Toit, 2011) was utilized to test hypotheses regarding antecedents of individual level perceptions of patient safety climate to account for the fact that individuals were nested within hospital units. Traditional multiple regression analyses were utilized to test unit level hypotheses examining the relationships between unit level patient safety climate and patient outcomes. Results indicated that unit membership was significantly related to individual climate perceptions-specifically, individual-level climate profile elevation. In turn, individual climate profile elevation and profile variability were related to employee willingness to recommend their organization to family and friends in need of care. At the unit level of analysis, climate profile variability was significantly related to patient willingness to recommend the organization to others, and climate shape was found to be related to patient safety. Furthermore, these results were not dependent on climate strength. The current study meaningfully contributes to the conceptual understanding of the patient safety climate construct by examining the degree to which configural aspects of the construct are predictive of important outcomes across multiple levels of analysis. In this way, it extends beyond existing studies of climate configurations to examine relationships at multiple levels of analysis and to also examine the moderating effects of climate strength. Practically, results provide insight into how the construct of patient safety climate can be used diagnostically and prescriptively to improve patient care and the working environment for providers. In addition to contributing to the theoretical understanding of the patient safety climate construct, this study also augments the evidence-base available to administrators, front-line providers, and regulators regarding how patient safety climate can be used to guide and align quality improvement efforts for greatest impact.
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Date Issued
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2011
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Identifier
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CFE0003992, ucf:48668
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0003992
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Title
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FINDING THE DOMINANT CHARACTERISTICS THAT CONTRIBUTE TO EFFECTIVELY IMPLEMENTING BEST PRACTICES IN PRIMARY INCLUSION CLASSROOMS USING THE INCLUSIVE CLASSROOM PROFILE (ICP).
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Creator
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Romero, Marilyn, Reyes-Macpherson, Maria, University of Central Florida
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Abstract / Description
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In 1997, the Individuals with Disabilities Education Act (IDEA) was amended to emphasize the need for students with disabilities to have access to the general curriculum. Along with IDEA, No Child Left Behind (NCLB), emphasized that all children must have a fair, equal, and significant opportunity to obtain a high-quality education (Sec. 1001, Part A, Title 1 of ESEA; 20U.S.C. 6301) increasing the need for effective inclusion classrooms in schools around the country. This study evaluated six...
Show moreIn 1997, the Individuals with Disabilities Education Act (IDEA) was amended to emphasize the need for students with disabilities to have access to the general curriculum. Along with IDEA, No Child Left Behind (NCLB), emphasized that all children must have a fair, equal, and significant opportunity to obtain a high-quality education (Sec. 1001, Part A, Title 1 of ESEA; 20U.S.C. 6301) increasing the need for effective inclusion classrooms in schools around the country. This study evaluated six inclusive classrooms (three partial and three full) from a large metropolitan school district in Florida. The classrooms' best practices were assessed using the Inclusive Classroom Profile (ICP). The ICP is a 7-point rating scale conducted through an observation procedure that is designed to assess the quality of daily classroom practices of children with disabilities (Soukakou, 2007). Teacher characteristics, student characteristics, and classroom characteristics were gathered from all classrooms and analyzed through correlation tests with the ICP scores. Although statistical results did not demonstrate statistically significant data in regards to the strength of relationships between these characteristics and ICP scores, the direction of the relationship on the following characteristics: related experience, severity of disabilities, and level of support, revealed a possible impact on ICP scores.
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Date Issued
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2012
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Identifier
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CFH0004181, ucf:44848
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH0004181
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Title
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SOIL MICROBIAL COMMUNITY DYNAMICS IN FLORIDA SCRUB ECOSYSTEM.
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Creator
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Albarracín, María, Weishampel, John F., University of Central Florida
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Abstract / Description
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Pyrogenic ecosystems are maintained by fires which vary in frequency, seasonality, and intensity. Florida oak-saw palmetto scrub ecosystem is characterized by fires occurring at intervals of 10-20 years. Diverse factors as private land acquisition and development has created a patchy distribution of scrub ecosystems and also interrupted the natural fire cycle. The effects of fire over plant regeneration and fauna habitat utilization of the scrub have been well characterized in previous...
Show morePyrogenic ecosystems are maintained by fires which vary in frequency, seasonality, and intensity. Florida oak-saw palmetto scrub ecosystem is characterized by fires occurring at intervals of 10-20 years. Diverse factors as private land acquisition and development has created a patchy distribution of scrub ecosystems and also interrupted the natural fire cycle. The effects of fire over plant regeneration and fauna habitat utilization of the scrub have been well characterized in previous research. In the present paper the objective is to characterize the short- and long-term fire effects on the soil microbial community. Fire effects were studied in a chronosequence, comprising a recently burned scrub during a winter-prescribed fire to scrub where fire did not occur for 40 years. The number of culturable cells was reduced by two orders of magnitude by indirect fire effects and environmental factors, principally hydric stress. However, the duration of fire effects was very short since the microbial community returned to pre-fire numbers and activity by day 47 after fire. Microbial community activity was distinctively related to inoculum density in the soil and litter samples. Soil and litter microbial communities showed differences in metabolic activity. There was no difference in substrate utilization pattern, but there was significant seasonal variation related to the decrease in water content during the month of May. Substrate utilization by litter microbial communities was higher during the month of January compared to soil microbial communities and this relationship was inversed during the month of May probably associated to the more stringent conditions, low water availability, on the litter layer. Seasonal effects outweighed fire effects in this study as this environmental constraint determined the microbial community structure and activity.
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Date Issued
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2005
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Identifier
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CFE0000472, ucf:46353
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0000472
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Title
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Development of Velocity Profile Generating Screens for Gas Turbine Components.
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Creator
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Tate, Joseph, Kapat, Jayanta, Gordon, Ali, Ahmed, Kareem, University of Central Florida
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Abstract / Description
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Laboratory experiments on components of complex systems such as gas turbines require many conditions to be met. Requirements to be met in order to simulate real world conditions include inlet flow conditions such as velocity profile, Reynold's number, and temperature. The methodology to be introduced designs a velocity profile generating screen to match real world conditions through the use of perforated plates. The velocity profile generating screen is an array of jets arranged in a manner...
Show moreLaboratory experiments on components of complex systems such as gas turbines require many conditions to be met. Requirements to be met in order to simulate real world conditions include inlet flow conditions such as velocity profile, Reynold's number, and temperature. The methodology to be introduced designs a velocity profile generating screen to match real world conditions through the use of perforated plates. The velocity profile generating screen is an array of jets arranged in a manner to produce sections of different solidities, a ratio of area that obstructs fluid flow compared to that of the total area. In an effort to better understand the interaction between perforated plate sections of different solidities, a collection of experimental data sets is presented to characterize the plates. This includes identification of fluid flow regions with characterization of the flow dynamics, though the analysis of velocity and turbulence decay. The aim of this characterization is to determine how the perforated plate's solidity affects the velocity development downstream and the location at which the velocity profile being produced can be considered complete.
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Date Issued
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2015
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Identifier
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CFE0006011, ucf:51020
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006011
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Title
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Methodological Improvements in the mRNA Profiling Assays for Incorporation into DNA Casework Workflows.
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Creator
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Volk, Paris, Ballantyne, John, Gerasimova, Yulia, Baudelet, Matthieu, University of Central Florida
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Abstract / Description
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Currently, DNA profiling is the gold standard to identify an individual. However, determining body fluid origin is important in criminal investigations, offering additional information surrounding the circumstances of a crime. However, crime labs can only definitively identify blood and semen and presumptively saliva using techniques that consume time and sample and do not simultaneously identify all forensically relevant body fluids. This causes many crime labs to want to bypass body fluid...
Show moreCurrently, DNA profiling is the gold standard to identify an individual. However, determining body fluid origin is important in criminal investigations, offering additional information surrounding the circumstances of a crime. However, crime labs can only definitively identify blood and semen and presumptively saliva using techniques that consume time and sample and do not simultaneously identify all forensically relevant body fluids. This causes many crime labs to want to bypass body fluid identification altogether. Therefore, advances into more definitive molecular-based body fluid methods are necessary. One such technique is mRNA profiling because it provides a highly sensitive and specific approach to definitively identifying all relevant body fluids in parallel. Although advancements have been made, improvements to mRNA profiling methodologies still need to be researched such as 1) possible mRNA recovery from established DNA workflows and 2) possible integration of mRNA profiling into an upfront male DNA screening assay for triaging sexual-assault evidence likely to contain male DNA and reduce/eliminate a significant bottleneck in the standard DNA workflow of microscopic sperm identification. This study was designed to address these two issues by evaluating a novel way to recover RNA, for body fluid identification, from the waste fractions of a PrepFiler(TM) DNA extraction, and from the DNA extracts directly. Next, this study aimed to provide a relatively quick molecular-based approach for screening sexual-assault evidence. It involves extraction of RNA using the Dynabeads(TM) mRNA DIRECT(TM) Kit, while saving the extraction waste fractions for downstream male-DNA quantitation and STR profiling. The RNA is then used in a rapid and sensitive 1-step combined reverse transcription-HRM assay to positively detect the presence of sperm. Both non-conventional co-extraction methods successfully addressed current body fluid identification challenges and allowed for easy integration into existing workflows when single sourced, mixture and mock casework samples were analyzed.
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Date Issued
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2019
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Identifier
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CFE0007551, ucf:52627
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007551
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Title
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PROFILING BY ANY OTHER NAME COULD BE THE FOREIGN INTELLIGENCE SURVEILLANCE ACT.
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Creator
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Malloy, Evan, Brown, Cynthia, University of Central Florida
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Abstract / Description
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The undergraduate thesis began with the research question of whether the Islamic community is being profiled by the use of the Foreign Intelligence Surveillance Act (FISA) following the terrorist attacks on September 11, 2001. At the beginning of the project, the researcher's hypothesis was that Muslim community had fallen victim to profiling through the use of electronic surveillance conducted by the American government. The research presented reveals a pattern of profiling and injustices...
Show moreThe undergraduate thesis began with the research question of whether the Islamic community is being profiled by the use of the Foreign Intelligence Surveillance Act (FISA) following the terrorist attacks on September 11, 2001. At the beginning of the project, the researcher's hypothesis was that Muslim community had fallen victim to profiling through the use of electronic surveillance conducted by the American government. The research presented reveals a pattern of profiling and injustices against many different groups of Americans throughout the history of United States surveillance laws starting with the illegal alcohol producers in the 1920's. Amendments to FISA have set necessary modern electronic surveillance regulations back 30 years. The researcher brings to light the injustices the Islamic community has endured out of the panic caused by the attacks on 9/11. The research presented was achieved by using empirical legal studies techniques of incorporating a mix-methods approach to utilize both quantitative and qualitative research components. The researcher developed a spreadsheet that included all published federal opinions of prosecutions involving FISA since its enactment in 1978. Statistical data was analyzed using frequency and average software, known as Stata, and the results of study suggest an extreme increase in the amount of prosecutions involving the Islamic community since 9/11 compared to prior.
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Date Issued
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2011
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Identifier
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CFH0003853, ucf:44694
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH0003853
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Title
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HYBRID PHOTONIC SIGNAL PROCESSING.
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Creator
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Ghauri, Farzan, Riza, Nabeel, University of Central Florida
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Abstract / Description
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This thesis proposes research of novel hybrid photonic signal processing systems in the areas of optical communications, test and measurement, RF signal processing and extreme environment optical sensors. It will be shown that use of innovative hybrid techniques allows design of photonic signal processing systems with superior performance parameters and enhanced capabilities. These applications can be divided into domains of analog-digital hybrid signal processing applications and free-space-...
Show moreThis thesis proposes research of novel hybrid photonic signal processing systems in the areas of optical communications, test and measurement, RF signal processing and extreme environment optical sensors. It will be shown that use of innovative hybrid techniques allows design of photonic signal processing systems with superior performance parameters and enhanced capabilities. These applications can be divided into domains of analog-digital hybrid signal processing applications and free-space--fiber-coupled hybrid optical sensors. The analog-digital hybrid signal processing applications include a high-performance analog-digital hybrid MEMS variable optical attenuator that can simultaneously provide high dynamic range as well as high resolution attenuation controls; an analog-digital hybrid MEMS beam profiler that allows high-power watt-level laser beam profiling and also provides both submicron-level high resolution and wide area profiling coverage; and all optical transversal RF filters that operate on the principle of broadband optical spectral control using MEMS and/or Acousto-Optic tunable Filters (AOTF) devices which can provide continuous, digital or hybrid signal time delay and weight selection. The hybrid optical sensors presented in the thesis are extreme environment pressure sensors and dual temperature-pressure sensors. The sensors employ hybrid free-space and fiber-coupled techniques for remotely monitoring a system under simultaneous extremely high temperatures and pressures.
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Date Issued
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2007
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Identifier
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CFE0001983, ucf:47423
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0001983
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Title
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TO CATCH A TERRORIST: THE IMPROPER USE OF PROFILING IN U.S. POST-9/11 COUNTERTERRORISM.
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Creator
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Crawford, Kamillia, Ravich, Timothy M., University of Central Florida
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Abstract / Description
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The attacks of September 11, 2001 (9/11) caused thousands of deaths, national and global panic, and immediate action by the federal government to protect the borders of the United States of America (USA) from terrorism. In response to these attacks, the United States (U.S.) government enacted laws for law enforcement agencies to protect against terrorist activities. Law enforcement agencies are effective in combating terrorism, but their measures contain a major flaw - the improper use of...
Show moreThe attacks of September 11, 2001 (9/11) caused thousands of deaths, national and global panic, and immediate action by the federal government to protect the borders of the United States of America (USA) from terrorism. In response to these attacks, the United States (U.S.) government enacted laws for law enforcement agencies to protect against terrorist activities. Law enforcement agencies are effective in combating terrorism, but their measures contain a major flaw - the improper use of race in profiling to address national security and public safety concerns. Racial profiling is an ineffective measure for preventing terrorism. There are solutions to correct this flaw through reconstructing training and implementing policies for all law enforcement agencies. The intent of this thesis is to discuss the history and the effectiveness of profiling in U.S. post-9/11 counterterrorism through theoretical research of peer-reviewed journals and articles, relevant laws, and United States Supreme Court cases to offer solutions to the problems racial profiling presents. The discussion will generate a search for new ways law enforcement agencies could conduct daily counterterrorism operations.
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Date Issued
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2016
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Identifier
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CFH2000057, ucf:45534
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH2000057
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Title
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Trust-Based Rating Prediction and Malicious Profile Detection in Online Social Recommender Systems.
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Creator
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Davoudi, Anahita, Chatterjee, Mainak, Hu, Haiyan, Zou, Changchun, Rahnavard, Nazanin, University of Central Florida
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Abstract / Description
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Online social networks and recommender systems have become an effective channel for influencing millions of users by facilitating exchange and spread of information. This dissertation addresses multiple challenges that are faced by online social recommender systems such as: i) finding the extent of information spread; ii) predicting the rating of a product; and iii) detecting malicious profiles. Most of the research in this area do not capture the social interactions and rely on empirical or...
Show moreOnline social networks and recommender systems have become an effective channel for influencing millions of users by facilitating exchange and spread of information. This dissertation addresses multiple challenges that are faced by online social recommender systems such as: i) finding the extent of information spread; ii) predicting the rating of a product; and iii) detecting malicious profiles. Most of the research in this area do not capture the social interactions and rely on empirical or statistical approaches without considering the temporal aspects. We capture the temporal spread of information using a probabilistic model and use non-linear differential equations to model the diffusion process. To predict the rating of a product, we propose a social trust model and use the matrix factorization method to estimate user's taste by incorporating user-item rating matrix. The effect of tastes of friends of a user is captured using a trust model which is based on similarities between users and their centralities. Similarity is modeled using Vector Space Similarity and Pearson Correlation Coefficient algorithms, whereas degree, eigen-vector, Katz, and PageRank are used to model centrality. As rating of a product has tremendous influence on its saleability, social recommender systems are vulnerable to profile injection attacks that affect user's opinion towards favorable or unfavorable recommendations for a product. We propose a classification approach for detecting attackers based on attributes that provide the likelihood of a user profile of that of an attacker. To evaluate the performance, we inject push and nuke attacks, and use precision and recall to identify the attackers. All proposed models have been validated using datasets from Facebook, Epinions, and Digg. Results exhibit that the proposed models are able to better predict the information spread, rating of a product, and identify malicious user profiles with high accuracy and low false positives.
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Date Issued
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2018
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Identifier
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CFE0007168, ucf:52245
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007168
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Title
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Implementation of Optical Interferometry and Spectral Reflectometry for High Fidelity Thin Film Measurements.
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Creator
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Arends-Rodriguez, Armando, Putnam, Shawn, Chow, Louis, Kauffman, Jeffrey, University of Central Florida
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Abstract / Description
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An in-house reflectometer/interferometer has been built to investigate the varying curvature and thickness profiles in the contact line region of air, acetone, iso-octane, ethanol, and water on various types of substrates. Light intensity measurements were obtained using our reflectometer/interferomter and then analyzed in MATLAB to produce thickness and curvature profiles. The apparatus is based on the principle of a reflectometer, consisting of different optical elements, probe, light...
Show moreAn in-house reflectometer/interferometer has been built to investigate the varying curvature and thickness profiles in the contact line region of air, acetone, iso-octane, ethanol, and water on various types of substrates. Light intensity measurements were obtained using our reflectometer/interferomter and then analyzed in MATLAB to produce thickness and curvature profiles. The apparatus is based on the principle of a reflectometer, consisting of different optical elements, probe, light source, and spectrometer. Our reflectometer/interferomter takes measurements in the UV-Vis-IR range (200nm-1000nm). This range is achieved by using a light source that has both a deuterium light (190nm-800nm), a tungsten halogen light (400nm-1100nm), a Metal-Core Printed Circuit Board LED (800nm-1000nm) and a Metal-Core Printed Circuit board cold white LED (400nm-800nm, 6500 K). A UV-VIS-IR spectrometer reads the light response after light is focused on the region of interest. Then a CCD camera (2448x2048) records the profiles for image analyzing interferometry. The readings were then validated based on results in the literature and studies with cylindrical lens samples.
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Date Issued
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2017
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Identifier
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CFE0006559, ucf:51328
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006559
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Title
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TOWARDS DIRECT WRITING OF 3-D PHOTONIC CIRCUITS USING ULTRAFAST LASERS.
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Creator
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Zoubir, Arnaud, Richardson, Martin, University of Central Florida
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Abstract / Description
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The advent of ultrafast lasers has enabled micromachining schemes that cannot be achieved by other current techniques. Laser direct writing has emerged as one of the possible routes for fabrication of optical waveguides in transparent materials. In this thesis, the advantages and limitations of this technique are explored. Two extended-cavity ultrafast lasers were built and characterized as the laser sources for this study, with improved performance over existing systems. Waveguides are...
Show moreThe advent of ultrafast lasers has enabled micromachining schemes that cannot be achieved by other current techniques. Laser direct writing has emerged as one of the possible routes for fabrication of optical waveguides in transparent materials. In this thesis, the advantages and limitations of this technique are explored. Two extended-cavity ultrafast lasers were built and characterized as the laser sources for this study, with improved performance over existing systems. Waveguides are fabricated in oxide glass, chalcogenide glass, and polymers, these being the three major classes of materials for the telecommunication industry. Standard waveguide metrology is performed on the fabricated waveguides, including refractive index profiling and mode analysis. Furthermore, a finite-difference beam propagation method for wave propagation in 3D-waveguides is proposed. The photo-structural modifications underlying the changes in the material optical properties after exposure are investigated. The highly nonlinear processes of the light/matter interaction during the writing process are described using a free electron model. UV/visible absorption spectroscopy, photoluminescence spectroscopy and Raman spectroscopy are used to assess the changes occurring at the atomic level. Finally, the impact of laser direct writing on nonlinear waveguide applications is discussed.
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Date Issued
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2004
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Identifier
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CFE0000236, ucf:46252
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0000236
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Title
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PHYSICAL CHARACTERISTICS OF AN INDIVIDUAL: THE IDENTIFICATION OF BIOMARKERS FOR BIOLOGICAL AGE DETERMINATION.
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Creator
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Alvarez, Michelle, Ballantyne, Jack, University of Central Florida
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Abstract / Description
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It is now a matter of routine for the forensic scientist to obtain the genetic profile of an individual from DNA recovered from a biological stain deposited at a crime scene. Potential contributors of the stain must either be known to investigators (i.e. a developed suspect) or the questioned profile must be searched against a database of DNA profiles such as those maintained in the CODIS National DNA database. However, in those instances where there is no developed suspect and no match is...
Show moreIt is now a matter of routine for the forensic scientist to obtain the genetic profile of an individual from DNA recovered from a biological stain deposited at a crime scene. Potential contributors of the stain must either be known to investigators (i.e. a developed suspect) or the questioned profile must be searched against a database of DNA profiles such as those maintained in the CODIS National DNA database. However, in those instances where there is no developed suspect and no match is obtained after interrogation of appropriate DNA databases, the DNA profile per se presently provides no meaningful information to investigators, with the notable exception of gender determination. In these situations it would be advantageous to the investigation, if additional probative information could be obtained from the biological stain. A useful biometric that could provide important probative information, and one that may be amenable to molecular genetic analysis, is the biological age of an individual. The ability to provide investigators with information as to whether a DNA donor is a newborn, infant, toddler, child, adolescent, adult, middle-aged or elderly individual could be useful in certain cases, particularly those involving young children such as kidnappings or in providing additional intelligence during terrorist investigations. Currently no validated molecular assays exist for age determination. Biological human ageing can be defined by two distinct processes, degenerative and developmental ageing. The degenerative process of ageing is based on theories which identify an increase or decrease in physiological conditions with increasing age. In contrast, the developmental process of ageing is based on the theory that as individuals increase in chronological age, there will be subtle corresponding molecular based biological changes, each requiring genes to be expressed or silenced, indicative of that particular stage of life. We investigated the degenerative process of chromosomal telomere shortening, as well as the developmental process of gene expression profiling analysis, in an attempt to identify biomarkers of biological age in a self-renewing tissue such as blood. While telomere length analysis was an ineffective method for age determination; gene expression analysis revealed three gene transcripts expressed in an age-dependent physiological manner. These species namely- COL1A2, HBE1 and IGFBP3, were found to be expressed at elevated levels in younger individuals, newborns, or post-pubertal individuals, respectively. The biological process of hemoglobin switching was also investigated for the possibility of determining human age. While experimenting with the potential of using the gamma-hemoglobin chains, as newborn specific gene candidates, we serendipitously discovered four novel truncated transcripts, which we have termed HBG1n1, HBG1n2, HBG2n2 and HBG2n3; whose expression was restricted to whole-blood newborn samples and specific fetal tissues. The molecular origin of these transcripts appears to be at the RNA level, being produced by specific rearrangement events occurring in the standard gamma hemoglobin transcripts (HBG1 and HBG2), which yield these new isoforms that are expressed in a highly regulated tissue specific manner.
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Date Issued
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2007
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Identifier
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CFE0001737, ucf:47297
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0001737
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Title
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THE INTEGRATED USER EXPERIENCE EVALUATION MODEL: A SYSTEMATIC APPROACH TO INTEGRATING USER EXPERIENCE DATA SOURCES.
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Creator
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Champney, Roberto, Malone, Linda, University of Central Florida
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Abstract / Description
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Evaluating the user experience (UX) associated with product interaction is a challenge for current human-systems developers. This is largely due to a lack of theoretical guidance for directing how best to assess the UX and a paucity of tools to support such evaluation. This dissertation provided a framework and tools for guiding and supporting evaluation of the user experience. This doctoral research involved reviewing the literature on UX, using this knowledge to build first build a...
Show moreEvaluating the user experience (UX) associated with product interaction is a challenge for current human-systems developers. This is largely due to a lack of theoretical guidance for directing how best to assess the UX and a paucity of tools to support such evaluation. This dissertation provided a framework and tools for guiding and supporting evaluation of the user experience. This doctoral research involved reviewing the literature on UX, using this knowledge to build first build a theoretical model of the UX construct and later develop a theoretical model to for the evaluation of UX in order to aid evaluators the integrated User eXperience EValuation (iUXEV), and empirically validating select components of the model through three case studies. The developed evaluation model was subjected to a three phase validation process that included the development and application of different components of the model separately. The first case study focused on developing a tool and method for assessing the affective component of UX which resulted in lessons learned for the integration of the tool and method into the iUXEV model. The second case study focused on integrating several tools that target different components of UX and resulted in a better understanding of how the data could be utilized as well as identify the need for an integration method to bring the data together. The third case study focused on the application of the results of an usability evaluation on an organizational setting which resulted in the identification of challenges and needs faced by practitioners. Taken together, this body of research, from the theoretically-driven iUXEV model to the newly developed emotional assessment tool, extends the user experience / usability body of knowledge and state-of-practice for interaction design practitioners who are challenged with holistic user experience evaluations, thereby advancing the state-of-the-art in UX design and evaluation.
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Date Issued
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2009
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Identifier
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CFE0002761, ucf:48098
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0002761
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Title
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MESSENGER RNA PROFILING: A PROTOTYPE METHOD FOR BODY FLUIDAND TISSUE IDENTIFICATION.
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Creator
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Juusola, Jane, Ballantyne, Jack, University of Central Florida
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Abstract / Description
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Conventional methods of body fluid identification use labor-intensive, technologically diverse techniques that are performed in a series, not parallel, manner and are costly in terms of time and sample. Furthermore, for some frequently encountered body fluids, such as saliva or vaginal secretions, no confirmatory technique exists. Terminally differentiated cells, such as blood lymphocytes or epithelial cells lining the oral cavity, have a unique pattern of gene expression, which is evinced by...
Show moreConventional methods of body fluid identification use labor-intensive, technologically diverse techniques that are performed in a series, not parallel, manner and are costly in terms of time and sample. Furthermore, for some frequently encountered body fluids, such as saliva or vaginal secretions, no confirmatory technique exists. Terminally differentiated cells, such as blood lymphocytes or epithelial cells lining the oral cavity, have a unique pattern of gene expression, which is evinced by the presence and relative abundance of specific mRNA species. If the type and abundance of mRNAs can be determined in a stain or tissue sample recovered at the crime scene, it would be possible to definitively identify the tissue or body fluid in question. Advantages of an mRNA-based approach, compared to conventional biochemical analysis, include greater specificity, simultaneous and semi-automated analysis though a common assay format, improved timeliness, decreased sample consumption and compatibility with DNA extraction methodologies. In this report, we demonstrate that RNA is stable in biological stains and can be recovered in sufficient quantity and quality for analysis using reverse transcriptasepolymerase chain reaction assay (RT-PCR). We have identified sets of candidate tissuespecific genes for body fluids and tissues of forensic interest, namely blood, saliva, semen, vaginal secretions, menstrual blood, urine, skin, muscle, adipose, and brain. We also report the identification of a new housekeeping gene for use in mRNA based assays. Select body fluid-specific genes have been incorporated into multiplex PCR and real-time PCR assays. These assays allow for the positive identification of blood, saliva, semen,vaginal secretions, and/or menstrual blood in a stain. The final task of this work was the molecular characterization of mRNA degradation patterns in biological stains, which not only has fundamental importance in possibly revealing mRNA degradation pathways in dried biological stains, but may ultimately lead to better assay design strategies for mRNA markers for forensic use. An mRNA-based approach described in this report could allow the facile identification of the tissue components present in a body fluid stain and could conceivably supplant the battery of serological and biochemical tests currently employed in the forensic serology laboratory.
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Date Issued
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2005
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Identifier
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CFE0000862, ucf:46668
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0000862
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Title
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The Effects of Phosphatidylserine on Reaction Time and Cognitive Function Following an Exercise Stress.
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Creator
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Wells, Adam, Hoffman, Jay, Fragala, Maren, Stout, Jeffrey, University of Central Florida
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Abstract / Description
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Phosphatidylserine (PS) is an endogenously occurring phospholipid that has been shown to have cognition and mood enhancing properties in humans, possibly through its role as an enzyme co-factor in cellular signal transduction. Specifically, PS has been identified as activator of classical isoforms of protein kinase C, an enzyme known to be involved in the growth and differentiation of neural cells, and is therefore thought to play a role in the protection of neurons.The purpose of this study...
Show morePhosphatidylserine (PS) is an endogenously occurring phospholipid that has been shown to have cognition and mood enhancing properties in humans, possibly through its role as an enzyme co-factor in cellular signal transduction. Specifically, PS has been identified as activator of classical isoforms of protein kinase C, an enzyme known to be involved in the growth and differentiation of neural cells, and is therefore thought to play a role in the protection of neurons.The purpose of this study was to examine the effects of supplementation with PS and caffeine on measures of cognition, reaction time and mood prior to and following an exercise stress. Twenty, healthy, resistance trained males (17) and females (3) (mean (&)#177; SD; age: 22.75 (&)#177; 3.27 yrs; height: 177.03 (&)#177; 8.44cm; weight: 78.98 (&)#177; 11.24kg; body fat%: 14.28 (&)#177; 6.6), volunteered to participate in this randomized, double-blind, placebo-controlled study. Participants were assigned to a PS group (400mg/day PS; 100mg/day caffeine, N=9) or PL (16g/day Carbs, N=11) delivered in the form of 4 candy chews identical in size, shape and color. Subjects performed an acute bout of full body resistance exercise, prior to (T1) and following 14 days of supplementation (T2). Measures of reaction time (Dynavision(&)#174; D2 Visuomotor Training Device), cognition (Serial Subtraction Test, SST), and mood (Profile of Mood States, POMS) were assessed immediately before and following resistance exercise in both T1 and T2. Data was analyzed using two-way ANCOVA and repeated measures ANOVA.Supplementation with 400mg PS and 100mg caffeine did not have a significant impact upon measures of reaction time or cognition between groups at baseline or following acute resistance exercise. However, there was a non-significant trend to the attenuation of fatigue between groups, following acute resistance exercise (p = 0.071). Interestingly, our data suggests that acute resistance exercise alone may improve cognitive function.Although more research is necessary regarding optimal dosage and supplementation duration, the current findings suggest that supplementation 400mg/day PS with 100mg/day caffeine may attenuate fatigue following acute resistance exercise. It is possible that the lack of significance may be the result of both an inhibition of the PS activated pathway and a withdrawal effect from caffeine.
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Date Issued
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2012
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Identifier
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CFE0004457, ucf:49325
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0004457
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Title
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Development of Micro Volume DNA and RNA Profiling Assays to Identify the Donor and Tissue Source of Origin of Trace Forensic Biological Evidence.
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Creator
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Morgan, Brittany, Ballantyne, John, Kolpashchikov, Dmitry, Ye, Jingdong, University of Central Florida
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Abstract / Description
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In forensic casework analysis it is necessary to obtain genetic profiles from increasingly smaller amounts of biological material left behind by perpetrators of crime. The ability to obtain profiles from trace biological evidence is demonstrated with so-called 'touch DNA evidence' which is perceived to be the result of DNA obtained from shed skin cells transferred from donor to an object or person during physical contact. However, the current method of recovery of trace DNA involves cotton...
Show moreIn forensic casework analysis it is necessary to obtain genetic profiles from increasingly smaller amounts of biological material left behind by perpetrators of crime. The ability to obtain profiles from trace biological evidence is demonstrated with so-called 'touch DNA evidence' which is perceived to be the result of DNA obtained from shed skin cells transferred from donor to an object or person during physical contact. However, the current method of recovery of trace DNA involves cotton swabs or adhesive tape to sample an area of interest. This (")blind-swabbing(") approach may result in the recovery of biological material from different individuals resulting in admixed DNA profiles which are often difficult to interpret. Profiles recovered from these samples are reported to be from shed skin cells with no biological basis for that determination. A specialized approach for the isolation of single or few cells from 'touch DNA evidence' is necessary to improve the analysis and interpretation of recovered profiles. Here we describe the development of optimized and robust micro volume PCR reactions (1-5 uL) to improve the sensitivity and efficiency of 'touch DNA' analysis. These methods will permit not only the recovery of the genetic profile of the donor of the biological material, but permit an identification of the tissue source of origin using mRNA profiling. Results showed that the 3.5 uL amplification volume, a fraction of the standard 25 uL amplification volume, was the most ideal volume for the DNA assay, as it had very minimal evaporation with a 50% profile recovery rate at a single cell equivalent input (~5 pg) with reducing amplification volume alone. Findings for RNA showed that by reducing both amplification steps, reverse transcriptase PCR (20 uL) and body fluid multiplex PCR (25 uL), to 5 uL, ideal results were obtained with an increase in sensitivity and detection of six different body fluids down to 50 pg. Once optimized at the trace level, the assays were applied to the collection of single and few cells. DNA findings showed that about 40% of a full profile could be recovered from a single buccal cell, with nearly 80% of a full profile recovered from only two cells. RNA findings from collected skin particles of (")touched(") surfaces showed accurate skin detection down to 25 particles and detection in one clump of particles. The profiles recovered were of high quality and similar results were able to be replicated through subsequent experiments. More studies are currently underway to optimize these developed assays to increase profile recovery at the single cell level. Methods of doing so include comparing different locations on touched surfaces for highest bio-particle recovery and the development of physical characteristics of bio-particles that would provide the most ideal results.
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Date Issued
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2013
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Identifier
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CFE0005385, ucf:50468
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005385
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Title
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A Framework of Critical Success Factors for Business Organizations that Lead to Performance Excellence Based on a Financial and Quality Systems Assessment.
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Creator
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Francisco, Melissa, Elshennawy, Ahmad, Karwowski, Waldemar, Rabelo, Luis, Xanthopoulos, Petros, Weheba, Gamal, University of Central Florida
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Abstract / Description
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One of the most important tasks that business leaders undertake in order to achieve a superior market position is strategic planning. Beyond this obligation, business owners desire to maximize profit and maintain steady growth. In order to do this, resources must be invested in the most efficient way possible in order to achieve performance excellence. Adjusting business operations quickly, however, especially in times of economic uncertainty, is extremely difficult. Business leaders...
Show moreOne of the most important tasks that business leaders undertake in order to achieve a superior market position is strategic planning. Beyond this obligation, business owners desire to maximize profit and maintain steady growth. In order to do this, resources must be invested in the most efficient way possible in order to achieve performance excellence. Adjusting business operations quickly, however, especially in times of economic uncertainty, is extremely difficult. Business leaders therefore need insight into which elements of organizational improvement are most effective in order to strategically invest their resources to achieve superior performance in the most efficient way possible.This research examines the results of companies which have a demonstrated ability to achieve performance excellence as defined by the National Institute of Standards and Technology's Malcolm Baldrige Criteria for Performance Excellence. This research examined award-winning applications to determine common input factors, compared the business results of a subset of those award-winners with the overall market for a time-frame of 11 years, and then investigated the profitability, liquidity, debt management, asset management, and per share performance ratios of award-winners compared with their industry peers over 11 years as well.The main focus of this research is to determine whether participation in performance excellence best practices have created value for shareholders and business owners. This objective is achieved through the analysis of performance results of award winning companies. This research demonstrates that the integration of efforts associated with performance excellence is in-fact advantageous.
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Date Issued
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2014
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Identifier
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CFE0005331, ucf:50503
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005331
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Title
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Investigating the universality and comprehensive ability of measures to assess the state of workload.
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Creator
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Abich, Julian, Reinerman, Lauren, Lackey, Stephanie, Szalma, James, Taylor, Grant, University of Central Florida
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Abstract / Description
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Measures of workload have been developed on the basis of the various definitions, some are designed to capture the multi-dimensional aspects of a unitary resource pool (Kahneman, 1973) while others are developed on the basis of multiple resource theory (Wickens, 2002). Although many theory based workload measures exist, others have often been constructed to serve the purpose of specific experimental tasks. As a result, it is likely that not every workload measure is reliable and valid for all...
Show moreMeasures of workload have been developed on the basis of the various definitions, some are designed to capture the multi-dimensional aspects of a unitary resource pool (Kahneman, 1973) while others are developed on the basis of multiple resource theory (Wickens, 2002). Although many theory based workload measures exist, others have often been constructed to serve the purpose of specific experimental tasks. As a result, it is likely that not every workload measure is reliable and valid for all tasks, much less each domain. To date, no single measure, systematically tested across experimental tasks, domains, and other measures is considered a universal measure of workload. Most researchers would argue that multiple measures from various categories should be applied to a given task to comprehensively assess workload. The goal for Study 1 to establish task load manipulations for two theoretically different tasks that induce distinct levels of workload assessed by both subjective and performance measures was successful. The results of the subjective responses support standardization and validation of the tasks and demands of that task for investigating workload. After investigating the use of subjective and objective measures of workload to identify a universal and comprehensive measure or set of measures, based on Study 2, it can only be concluded that not one or a set of measures exists. Arguably, it is not to say that one will never be conceived and developed, but at this time, one does not reside in the psychometric catalog. Instead, it appears that a more suitable approach is to customize a set of workload measures based on the task. The novel approach of assessing the sensitivity and comprehensive ability of conjointly utilizing subjective, performance, and physiological workload measures for theoretically different tasks within the same domain contributes to the theory by laying the foundation for improving methodology for researching workload. The applicable contribution of this project is a stepping-stone towards developing complex profiles of workload for use in closed-loop systems, such as human-robot team interaction. Identifying the best combination of workload measures enables human factors practitioners, trainers, and task designers to improve methodology and evaluation of system designs, training requirements, and personnel selection.
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Date Issued
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2013
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Identifier
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CFE0005119, ucf:50675
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005119