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"BACK" TO THE FUTURE: AN EVALUATION OF MORPHOLOGICAL INTEGRATION IN KYPHOSIS
Title
"BACK" TO THE FUTURE: AN EVALUATION OF MORPHOLOGICAL INTEGRATION IN KYPHOSIS.
Creator
Ceuninck, Kristyna L, Starbuck, John, University of Central Florida
Abstract / Description
Morphological integration refers to the interdependence of two or more phenotypic structures. The morphological integration concept is based on the fact that parts of complex organisms do not vary randomly and instead display degrees of non-independence that are thought to occur from shared genetic or developmental origins, and/or functional demands. Integrated traits may develop, evolve, and be inherited together. One instance of morphological integration can be found between the vertebral...
Show moreMorphological integration refers to the interdependence of two or more phenotypic structures. The morphological integration concept is based on the fact that parts of complex organisms do not vary randomly and instead display degrees of non-independence that are thought to occur from shared genetic or developmental origins, and/or functional demands. Integrated traits may develop, evolve, and be inherited together. One instance of morphological integration can be found between the vertebral column and the skull. Due to the position of the skull resting atop of the vertebral column, posture may influence skull development and overall craniofacial morphology. Morphological integration within or between structures is typically statistically assessed by exploring correlation and covariation patterns among biological structures of interest. In this study, an analysis of morphological integration was carried out by studying covariation of morphometric measures from the vertebral column and craniofacial complex. Age- and sex-matched, de-identified computed tomography images of individuals with kyphosis spinal malformation (n = 15) and controls (n = 19) were acquired from Florida Hospital. It is hypothesized that the sample of individuals with kyphosis will exhibit statistically significant covariance differences relative to the control group for T6 vertebral and midfacial linear distance measurements. Anatomical landmarks were identified on the T6 thoracic vertebrae (n = 6) and the midfacial skeleton (n = 6), and XYZ coordinates were recorded for analysis. A subset of 10 individuals (5 kyphosis, 5 controls) individuals were measured on two occasions to assess reliability and measurement error. An Euclidean Distance Matrix Analysis (EDMA) of morphological integration was carried out on the entire sample by calculating correlation values for paired linear distance measurements (one vertebral and one midfacial) separately for the kyphosis and control samples (n = 225 for each sample). Next, EDMA calculated correlation differences and statistically assessed significance using a non-parametric bootstrap (1,000 resamples) and confidence interval testing (? ? 0.10). Only 35 of the 225 (15.56%) correlation differences were statistically significant. Patterns of variation among these significant correlation differences were explored by examining sample directionality of differences, sign patterns, and strengths. The relevance of these results to clinical and anthropological pursuits are discussed. Several recommendations for future investigations are made.
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Date Issued
2018
Identifier
CFH2000286, ucf:45812
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH2000286
Effect of Nonclassical Optical Turbulence on a Propagating Laser Beam
Title
Effect of Nonclassical Optical Turbulence on a Propagating Laser Beam.
Creator
Beason, Melissa, Phillips, Ronald, Atia, George, Richardson, Martin, Andrews, Larry, Shivamoggi, Bhimsen, University of Central Florida
Abstract / Description
Theory developed for the propagation of a laser beam through optical turbulence generally assumes that the turbulence is both homogeneous and isotropic and that the associated spectrum follows the classical Kolmogorov spectral power law of . If the atmosphere deviates from these assumptions, beam statistics such as mean intensity, correlation, and scintillation index could vary significantly from mathematical predictions. This work considers the effect of nonclassical turbulence on a...
Show moreTheory developed for the propagation of a laser beam through optical turbulence generally assumes that the turbulence is both homogeneous and isotropic and that the associated spectrum follows the classical Kolmogorov spectral power law of . If the atmosphere deviates from these assumptions, beam statistics such as mean intensity, correlation, and scintillation index could vary significantly from mathematical predictions. This work considers the effect of nonclassical turbulence on a propagated beam. Namely, anisotropy of the turbulence and a power law that deviates from . A mathematical model is developed for the scintillation index of a Gaussian beam propagated through nonclassical turbulence and theory is extended for the covariance function of intensity of a plane wave propagated through nonclassical turbulence. Multiple experiments over a concrete runway and a grass range verify the presence of turbulence which varies between isotropy and anisotropy. Data is taken throughout the day and the evolution of optical turbulence is considered. Also, irradiance fluctuation data taken in May 2018 over a concrete runway and July 2018 over a grass range indicate an additional beam shaping effect. A simplistic mathematical model was formulated which reproduced the measured behavior of contours of equal mean intensity and scintillation index.?
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Date Issued
2018
Identifier
CFE0007310, ucf:52646
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007310
Recognition of Complex Events in Open-source Web-scale Videos: Features, Intermediate Representations and their Temporal Interactions
Title
Recognition of Complex Events in Open-source Web-scale Videos: Features, Intermediate Representations and their Temporal Interactions.
Creator
Bhattacharya, Subhabrata, Shah, Mubarak, Guha, Ratan, Laviola II, Joseph, Sukthankar, Rahul, Moore, Brian, University of Central Florida
Abstract / Description
Recognition of complex events in consumer uploaded Internet videos, captured under real-world settings, has emerged as a challenging area of research across both computer vision and multimedia community. In this dissertation, we present a systematic decomposition of complex events into hierarchical components and make an in-depth analysis of how existing research are being used to cater to various levels of this hierarchy and identify three key stages where we make novel contributions,...
Show moreRecognition of complex events in consumer uploaded Internet videos, captured under real-world settings, has emerged as a challenging area of research across both computer vision and multimedia community. In this dissertation, we present a systematic decomposition of complex events into hierarchical components and make an in-depth analysis of how existing research are being used to cater to various levels of this hierarchy and identify three key stages where we make novel contributions, keeping complex events in focus. These are listed as follows: (a) Extraction of novel semi-global features -- firstly, we introduce a Lie-algebra based representation of dominant camera motion present while capturing videos and show how this can be used as a complementary feature for video analysis. Secondly, we propose compact clip level descriptors of a video based on covariance of appearance and motion features which we further use in a sparse coding framework to recognize realistic actions and gestures. (b) Construction of intermediate representations -- We propose an efficient probabilistic representation from low-level features computed from videos, basedon Maximum Likelihood Estimates which demonstrates state of the art performancein large scale visual concept detection, and finally, (c) Modeling temporal interactions between intermediate concepts -- Using block Hankel matrices and harmonic analysis of slowly evolving Linear Dynamical Systems, we propose two new discriminative feature spaces for complex event recognition and demonstratesignificantly improved recognition rates over previously proposed approaches.
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Date Issued
2013
Identifier
CFE0004817, ucf:49724
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004817