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TISSUE ENGINEERING THE MOTONEURON TO MUSCLE SEGMENT OF THE STRETCH REFLEX ARC CIRCUIT UTILIZING MICRO-FABRICATION, INTERFACE DESIGN AND DEFINED MEDIUM FORMULATION
Title
TISSUE ENGINEERING THE MOTONEURON TO MUSCLE SEGMENT OF THE STRETCH REFLEX ARC CIRCUIT UTILIZING MICRO-FABRICATION, INTERFACE DESIGN AND DEFINED MEDIUM FORMULATION.
Creator
DAS, MAINAK, Hickman, James, University of Central Florida
Abstract / Description
The stretch reflex circuit is one of the most primitive circuits of mammalian system and serves mainly to control the length of the muscle. It consists of four elements: the stretch sensor (muscle spindle/ intrafusal fiber lie parallel between extrafusal, contractile musculature), extrafusal muscle fiber, sensory neuron and motoneuron. The basic principle of the stretch reflex arc circuit is as follows: whenever there is a sudden stretch in a muscle, it needs to compensate back to its...
Show moreThe stretch reflex circuit is one of the most primitive circuits of mammalian system and serves mainly to control the length of the muscle. It consists of four elements: the stretch sensor (muscle spindle/ intrafusal fiber lie parallel between extrafusal, contractile musculature), extrafusal muscle fiber, sensory neuron and motoneuron. The basic principle of the stretch reflex arc circuit is as follows: whenever there is a sudden stretch in a muscle, it needs to compensate back to its original length so as to prevent any kind of injury. It performs this compensation process using a simple negative feed back circuit called the stretch reflex arc. Any form of stretch in a muscle activates the stretch sensors (muscle spindle/ intrafusal fiber) lying deep in each muscle. After the stretch sensors get activated, it sends a train of signals to the spinal cord through the sensory neurons. The sensory neurons relay this information to the motoneuron. The motoneuron performs the necessary information processing and sends the message to the extrafusal fibers so as to compensate for the sudden stretch action. The motoneuron conveys this message to the extrafusal fibers by communicating through the special synaptic junctions called neuromuscular junctions. Based on this information, the extrafusal fibers act accordingly so as to counter the effect of sudden stretch. This is also called the monosynaptic stretch reflex that involves a single synapse between a sensory neuron and a motoneuron. To date studying these stretch reflex circuits is only feasible in animal models. Almost no effort has been made to tissue engineer such circuits for a better understanding of the complex development and repair processes of the stretch reflex circuit formation. The long-term goal of this research is to tissue engineer a cellular prototype of the entire stretch reflex circuit. The specific theme of this dissertation research was to tissue engineer the motoneuron to muscle segment of the stretch reflex arc circuit utilizing micro-fabrication, interface design and defined medium formulations. In order to address this central theme, the following hypothesis has been proposed. The first part of the hypothesis is that microfabrication technology, interface design and defined medium formulations can be effectively combined to tissue engineer the motoneuron to muscle segment of the stretch reflex arc. The second part of the hypothesis is that different growth factors, hormones, nanoparticles, neurotransmitters and synthetic substrate can be optimally utilized to regenerate the adult mammalian spinal cord neurons so as to replace the embryonic motoneurons in the stretch reflex tissue engineered construct with adult motoneurons. In this body of work, the different tissue engineering strategies and technologies have been addressed to enable the recreation of a in vitro cellular prototype of the stretch reflex circuit with special emphasis on building the motoneuron to muscle segment of the circuit. In order to recreate the motoneuron to muscle segment of the stretch reflex arc, a successful methodology to tissue engineer skeletal muscle and motoneuron was essential. Hence the recreation of the motoneuron to muscle segment of the stretch reflex circuit was achieved in two parts. In the part 1 (Chapters 2-5), the challenges in skeletal muscle tissue engineering were examined. In part 2 (Chapters 6-7), apart from tissue engineering the motoneuron to muscle segment, the real time synaptic activity between motoneuron and muscle segment were studied using extensive video recordings. In part 3 (Chapters 8-10), an innovative attempt had been made to tissue engineer the adult mammalian spinal cord neurons so that in future this technology could utilized to replace the embryonic neurons used in the stretch reflex circuit with adult neurons. The advantage of using adult neurons is that it provides a powerful tool to study older neurons since these neurons are more prone to age related changes, neurodegenerative disorders and injuries. This study has successfully demonstrated the recreation of the motoneuron to muscle segment of the stretch reflex arc and further demonstrated the successful tissue engineering strategies to grow adult mammalian spinal cord neurons. The different cell culture technologies developed in these studies could be used as powerful tools in nerve-muscle tissue engineering, neuro-prosthetic devices and in regenerative medicine.
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Date Issued
2008
Identifier
CFE0002501, ucf:47679
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0002501
Inverse-Consistent Determination of Young's Modulus of Human Lung
Title
Inverse-Consistent Determination of Young's Modulus of Human Lung.
Creator
Seyfi Noferest, Behnaz, Ilegbusi, Olusegun, Santhanam, Anand, Kassab, Alain, Moslehy, Faissal, University of Central Florida
Abstract / Description
Human lung undergoes respiration-induced deformation due to sequential inhalation and exhalation. Accurate determination of lung deformation is crucial for tumor localization and targeted radiotherapy in patients with lung cancer. Numerical modeling of human lung dynamics based on underlying physics and physiology enables simulation and virtual visualization of lung deformation. Dynamical modeling is numerically complicated by the lack of information on lung elastic behavior, structural...
Show moreHuman lung undergoes respiration-induced deformation due to sequential inhalation and exhalation. Accurate determination of lung deformation is crucial for tumor localization and targeted radiotherapy in patients with lung cancer. Numerical modeling of human lung dynamics based on underlying physics and physiology enables simulation and virtual visualization of lung deformation. Dynamical modeling is numerically complicated by the lack of information on lung elastic behavior, structural heterogeneity as well as boundary constrains. This study integrates physics-based modeling and image-based data acquisition to develop the patient-specific biomechanical model and consequently establish the first consistent Young's modulus (YM) of human lung. This dissertation has four major components: (i) develop biomechanical model for computation of the flow and deformation characteristics that can utilize subject-specific, spatially-dependent lung material property; (ii) develop a fusion algorithm to integrate deformation results from a deformable image registration (DIR) and physics-based modeling using the theory of Tikhonov regularization; (iii) utilize fusion algorithm to establish unique and consistent patient specific Young's modulus and; (iv) validate biomechanical model utilizing established patient-specific elastic property with imaging dataThe simulation is performed on three dimensional lung geometry reconstructed from four-dimensional computed tomography (4DCT) dataset of human subjects. The heterogeneous Young's modulus is estimated from a linear elastic deformation model with the same lung geometry and 4D lung DIR. The biomechanical model adequately predicts the spatio-temporal lung deformation, consistent with data obtained from imaging. The accuracy of the numerical solution is enhanced through fusion with the imaging data beyond the classical comparison of the two sets of data. Finally, the fused displacement results are used to establish unique and consistent patient-specific elastic property of the lung.
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Date Issued
2015
Identifier
CFE0006391, ucf:51512
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006391
Real-time SIL Emulation Architecture for Cooperative Automated Vehicles
Title
Real-time SIL Emulation Architecture for Cooperative Automated Vehicles.
Creator
Gupta, Nitish, Pourmohammadi Fallah, Yaser, Rahnavard, Nazanin, Vosoughi, Azadeh, University of Central Florida
Abstract / Description
This thesis presents a robust, flexible and real-time architecture for Software-in-the-Loop (SIL) testing of connected vehicle safety applications. Emerging connected and automated vehicles (CAV) use sensing, communication and computing technologies in the design of a host of new safety applications. Testing and verification of these applications is a major concern for the automotive industry. The CAV safety applications work by sharing their state and movement information over wireless...
Show moreThis thesis presents a robust, flexible and real-time architecture for Software-in-the-Loop (SIL) testing of connected vehicle safety applications. Emerging connected and automated vehicles (CAV) use sensing, communication and computing technologies in the design of a host of new safety applications. Testing and verification of these applications is a major concern for the automotive industry. The CAV safety applications work by sharing their state and movement information over wireless communication links. Vehicular communication has fueled the development of various Cooperative Vehicle Safety (CVS) applications. Development of safety applications for CAV requires testing in many different scenarios. However, the recreation of test scenarios for evaluating safety applications is a very challenging task. This is mainly due to the randomness in communication, difficulty in recreating vehicle movements precisely, and safety concerns for certain scenarios. We propose to develop a standalone Remote Vehicle Emulator (RVE) that can reproduce V2V messages of remote vehicles from simulations or from previous tests, while also emulating the over the air behavior of multiple communicating nodes. This is expected to significantly accelerate the development cycle. RVE is a unique and easily configurable emulation cum simulation setup to allow Software in the Loop (SIL) testing of connected vehicle applications in a realistic and safe manner. It will help in tailoring numerous test scenarios, expediting algorithm development and validation as well as increase the probability of finding failure modes. This, in turn, will help improve the quality of safety applications while saving testing time and reducing cost.The RVE architecture consists of two modules, the Mobility Generator, and the Communication emulator. Both of these modules consist of a sequence of events that are handled based on the type of testing to be carried out. The communication emulator simulates the behavior of MAC layer while also considering the channel model to increase the probability of successful transmission. It then produces over the air messages that resemble the output of multiple nodes transmitting, including corrupted messages due to collisions. The algorithm that goes inside the emulator has been optimized so as to minimize the communication latency and make this a realistic and real-time safety testing tool. Finally, we provide a multi-metric experimental evaluation wherein we verified the simulation results with an identically configured ns3 simulator. With the aim to improve the quality of testing of CVS applications, this unique architecture would serve as a fundamental design for the future of CVS application testing.
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Date Issued
2018
Identifier
CFE0007185, ucf:52280
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007185
Characterization of gold black and its application in un-cooled infrared detectors
Title
Characterization of gold black and its application in un-cooled infrared detectors.
Creator
Panjwani, Deep, Peale, Robert, Chow, Lee, Del Barco, Enrique, Schoenfeld, Winston, University of Central Florida
Abstract / Description
Gold black porous coatings were thermally evaporated in the chamber backfilled with inert gas pressure and their optical properties were studied in near-far-IR wavelengths. The porosities of coatings were found to be extremely high around ~ 99%. Different approaches of effective medium theories such as Maxwell-Garnett, Bruggeman, Landau-Lifshitz-Looyenga and Bergman Formalism were utilized to calculate refractive index (n) and extinction coefficient (k). The aging induced changes on...
Show moreGold black porous coatings were thermally evaporated in the chamber backfilled with inert gas pressure and their optical properties were studied in near-far-IR wavelengths. The porosities of coatings were found to be extremely high around ~ 99%. Different approaches of effective medium theories such as Maxwell-Garnett, Bruggeman, Landau-Lifshitz-Looyenga and Bergman Formalism were utilized to calculate refractive index (n) and extinction coefficient (k). The aging induced changes on electrical and optical properties were studied in regular laboratory conditions using transmission electron microscopy, Fourier transform infrared spectroscopy, and fore-probe electrical measurements. A significant decrease in electrical resistance in as deposited coating was found to be consistent with changes in the granular structure with aging at room temperature. Electrical relaxation model was applied to calculate structural relaxation time in the coatings prepared with different porosities. Interestingly, with aging, absorptance of the coatings improved, which is explained using conductivity form of Bergman Formulism. Underlying aim of this work was to utilize gold blacks to improve sensitivity in un-cooled IR sensors consist of pixel arrays. To achieve this, fragile gold blacks were patterned on sub-mm length scale areas using both stenciling and conventional photolithography. Infrared spectral imaging with sub-micron spatial resolution revealed the spatial distribution of absorption across the gold black patterns produced with both the methods. Initial experiments on VOx-Au bolometers showed that, gold black improved the responsivity by 42%. This work successfully establishes promising role of gold black coatings in commercial un-cooled infrared detectors.
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Date Issued
2015
Identifier
CFE0005680, ucf:50197
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005680
THE REBIRTH OF CONSCIOUSNESS
Title
THE REBIRTH OF CONSCIOUSNESS.
Creator
Blaszak, Urszula, Hall, Scott, University of Central Florida
Abstract / Description
Human beings encounter cascades of a plethora of experiences, one after another, every single microsecond of our lives. There are many things happening around. The world is full of events and occurrences. As they happen, the mind reacts to every individual input. This is a very exhausting and difficult. Thus, people have developed a process of self-defense against this horrible mishmash of information. Their minds have this amazing capacity of sorting them out and making sense out of them....
Show moreHuman beings encounter cascades of a plethora of experiences, one after another, every single microsecond of our lives. There are many things happening around. The world is full of events and occurrences. As they happen, the mind reacts to every individual input. This is a very exhausting and difficult. Thus, people have developed a process of self-defense against this horrible mishmash of information. Their minds have this amazing capacity of sorting them out and making sense out of them. Humankind's survival depends on that. If one does not sort all this information out, one might not be able to make a simplest decision. As humans process the information, they learn to ignore and forget. They focus on their feelings and emotions. They forget the logic. The oversimplification process begins. Humans create rigid systems of oversimplified formulas. They assign adjectives to things, occurrences, and other people. The number of those adjectives is small. After assigning, those adjectives obscure everything else. A new world is created, stupid, limited, lazy, and in the end making humans very easy to control. What starts as a basic survival process ends up as a tool one can use to destroy the owners of the mind. In the end, the birth of consciousness leads to its death. My work fights this process. It aims to put a person back into that state of shock created by a mishmash of information and thus create the rebirth of consciousness.
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Date Issued
2007
Identifier
CFE0001673, ucf:47195
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0001673
YOU'VE GOT MAIL: THE STUDY OF THE ATTORNEY-CLIENT PRIVILEGE AND THE USE OF ELECTRONIC MAIL
Title
YOU'VE GOT MAIL: THE STUDY OF THE ATTORNEY-CLIENT PRIVILEGE AND THE USE OF ELECTRONIC MAIL.
Creator
McConnell, Justin, Cook, Kathy, University of Central Florida
Abstract / Description
The prolific use of the internet and electronic mail within the legal profession presents novel challenges to the application of the attorney-client privilege; especially, in regards to protecting intended confidential communications relayed through e-mail. This thesis addresses the question of whether an attorney in Florida, through electronic mail use, can waive his client's right to the protections of the attorney-client privilege. After a review of current case law, law review articles,...
Show moreThe prolific use of the internet and electronic mail within the legal profession presents novel challenges to the application of the attorney-client privilege; especially, in regards to protecting intended confidential communications relayed through e-mail. This thesis addresses the question of whether an attorney in Florida, through electronic mail use, can waive his client's right to the protections of the attorney-client privilege. After a review of current case law, law review articles, statutes, and texts, this thesis concluded that an attorney's communication through e-mail warrants a reasonable expectation of privacy, permitting the attorney to speak in reasonable confidence to clients through the web. However, attorneys, ethically, should consider the strong repercussions for using such a potentially transparent medium for communication. By examining the relationship between current law, the application of the attorney-client privilege, and a reasonable expectation of privacy, this study provides a comprehensive analysis for attorneys concerned with electronic mail usage. Lastly, this thesis provides attorneys with best practices for their electronic mail communications.
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Date Issued
2011
Identifier
CFH0003832, ucf:44756
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0003832
Theoretical Study of Negative Molecular Ions Relevant to the Interstellar and Laboratory Plasma
Title
Theoretical Study of Negative Molecular Ions Relevant to the Interstellar and Laboratory Plasma.
Creator
Khamesian, Marjan, Kokoouline, Viatcheslav, Argenti, Luca, Saha, Haripada, Masunov, Artem, University of Central Florida
Abstract / Description
Recently, several negative molecular ions, CnN? (n = 1, 3, 5) and CnH? (n = 4, 6, 8), were observed in the interstellar medium (ISM). It was suggested that the anions are formed in the ISM by the process of radiative electron attachment (REA). A simple statistical model was developed in 1980's to estimate rate coefficients of the REA reactions. Some of the rate coefficients obtained in the model are consistent with the observations, the others are not. More importantly, some of the...
Show moreRecently, several negative molecular ions, CnN? (n = 1, 3, 5) and CnH? (n = 4, 6, 8), were observed in the interstellar medium (ISM). It was suggested that the anions are formed in the ISM by the process of radiative electron attachment (REA). A simple statistical model was developed in 1980's to estimate rate coefficients of the REA reactions. Some of the rate coefficients obtained in the model are consistent with the observations, the others are not. More importantly, some of the approximations employed in the model are not physically justified.The aim of this thesis is a development of a quantum-mechanical approach to study the process of radiative electron attachment to linear molecules of astrophysical interest. The approach is based on accurate ab initio calculations of electronic bound and continuum states of the negative ion. Cross sections and rate coefficients for formation of the following molecular negative ions by REA were determined: CN?, C2H?, C3N?, C4H?, C5N?, C6H?, and C8H?. All the calculations presented in the thesis were carried out using the MOLPRO and UK R-matrix (Quantemol)suites of programs. Uncertainty quantification of the results, obtained for each studied system, was performed. A second process, closely related to the radiative electron attachment, photodetachment (PD), was also studied in the thesis. Photodetachment cross sections for the CnN? (n = 1, 3, 5), CnH? (n = 4, 6, 8) and C2? molecules were determined using an approach similar to the one employed for REA from the same transition dipole moment matrix elements. The obtained REA cross sections and rate coefficients were validated by comparing the present theoretical results with the experimental data from recent photodetachment experiments.The present results suggest that the observed abundance of these ions in the ISM can hardly be explained by the REA process. In other words, these anions are formed in the interstellar medium by a process different than radiative electron attachment.Dissociative electron attachment (DEA) is another process of anion formation, which could possibly explain formation of certain molecular anions in the ISM. The ClF attachment was studied using a first principle approach.A good agreement with experimental data was demonstrated.A theoretical approach to evaluate cross sections for rotational excitation of linear neutral molecules by an electron impact was developed and applied to acetylene, HCCH. The differential cross sections for e-HCCH scattering were calculated between energies 0.1 eV and 10 eV. The momentum transfer cross section and eigenphases for e-HCCH scattering were also calculated.
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Date Issued
2017
Identifier
CFE0006612, ucf:51295
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006612
PAUL VERHOEVEN, MEDIA MANIPULATION, AND HYPER-REALITY
Title
PAUL VERHOEVEN, MEDIA MANIPULATION, AND HYPER-REALITY.
Creator
Malchiodi, Emmanuel, Janz, Bruce, University of Central Florida
Abstract / Description
Dutch director Paul Verhoeven is a polarizing figure. Although many of his American made films have received considerable praise and financial success, he has been lambasted on countless occasions for his gratuitous use of sex, violence, and contentious symbolism - 1995s Showgirls was overwhelmingly dubbed the worst film of all time and 1997s Starship Troopers earned him a reputation as a fascist. Regardless of the controversy surrounding him, his science fiction films are a move beyond the...
Show moreDutch director Paul Verhoeven is a polarizing figure. Although many of his American made films have received considerable praise and financial success, he has been lambasted on countless occasions for his gratuitous use of sex, violence, and contentious symbolism - 1995s Showgirls was overwhelmingly dubbed the worst film of all time and 1997s Starship Troopers earned him a reputation as a fascist. Regardless of the controversy surrounding him, his science fiction films are a move beyond the conventions of the big blockbuster science fiction films of the 1980s (E.T. and the Star Wars trilogy are prime examples), revealing a deeper exploration of both sociopolitical issues and the human condition. Much like the novels of Philip K. Dick (and Verhoeven's 1990 film Total Recall - an adaptation of a Dick short story), Verhoeven's science fiction work explores worlds where paranoia is a constant and determining whether an individual maintains any liberty is regularly questionable. In this thesis I am basically exploring issues regarding power. Although I barely bring up the term power in it, I feel it is central. Power is an ambiguous term; are we discussing physical power, state power, objective power, subjective power, or any of the other possible manifestations of the word? The original Anglo-French version of power means to be able,asking whether it is possible for one to do something. In relation to Verhoeven's science fiction work each demonstrates the limitations placed upon an individual's autonomy, asking are the protagonists capable of independent agency or rather just environmental constructs reflecting the myriad influences surrounding them. Does the individual really matter in the post-modern world, brimming with countless signs and signifiers? My main objective in this writing is to demonstrate how this happens in Verhoeven's films, exploring his central themes and subtext and doing what science fiction does: hold a mirror up to the contemporary world and critique it, asking whether our species' current trajectory is beneficial or hazardous.
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Date Issued
2011
Identifier
CFH0003844, ucf:44697
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0003844