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1.
Omole, Imona C.
Crosslinked polyimide hollow fiber membranes for aggressive natural gas feed streams.
Degree: PhD, Chemical Engineering, 2008, Georgia Tech
URL: http://hdl.handle.net/1853/26591 
► Natural gas is one of the fastest growing primary energy sources in the world today. The increasing world demand for energy requires increased production of…
(more)
▼ Natural gas is one of the fastest growing primary energy sources in the world today. The increasing world demand for energy requires increased production of high quality natural gas. For the natural gas to be fed into the mainline gas transportation system, it must meet the pipe-line quality standards. Natural gas produced at the wellhead is usually "sub-quality" and contains various impurities such as CO2, H2S, and higher hydrocarbons, which must be removed to meet specifications.
Carbon dioxide is usually the most abundant impurity in natural gas feeds and high CO2 partial pressures in the feed can lead to plasticization, which causes loss of some methane product and may ultimately render the membrane ineffective. Moreover, the presence of highly sorbing higher hydrocarbons in the feed can further reduce membrane performance.
Covalent crosslinking has been shown to increase plasticization resistance in dense films by suppressing the degree of swelling and segmental chain mobility in the polymer, thereby preserving the selectivity of the membrane. This research focuses on extending the dense film success to asymmetric hollow fibers.
In this work, the effect of high pressure CO2 (up to 400 psia CO2 partial pressure) on CO2/CH4 mixed gas separation performance was investigated on defect-free the hollow fiber membrane at different degrees of crosslinking. All the crosslinked fibers were shown to exhibit good resistance to selectivity losses from CO2 induced plasticization, significantly more than the uncrosslinked fibers. Robust resistance of the hollow fiber membranes in the presence of toluene (a highly sorbing contaminant) was also demonstrated as the membranes showed no plasticization. Antiplasticization was found to occur in the presence of toluene feeds with the crosslinkable fibers used in this work.
Advisors/Committee Members: Dr. William J. Koros (Committee Chair), Dr. Amyn Teja (Committee Member), Dr. Christopher W. Jones (Committee Member), Dr. Haskell W. Beckham (Committee Member), Dr. Stephen J. Miller (Committee Member).
Subjects/Keywords: Membrane; Carbon dioxide; Natural gas; Hollow fiber; Polyimide; Gas separation; Gas separation membranes; High pressure (Technology); Natural gas; Crosslinked polymers
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APA (6th Edition):
Omole, I. C. (2008). Crosslinked polyimide hollow fiber membranes for aggressive natural gas feed streams. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/26591
Chicago Manual of Style (16th Edition):
Omole, Imona C. “Crosslinked polyimide hollow fiber membranes for aggressive natural gas feed streams.” 2008. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/26591.
MLA Handbook (7th Edition):
Omole, Imona C. “Crosslinked polyimide hollow fiber membranes for aggressive natural gas feed streams.” 2008. Web. 20 Jan 2021.
Vancouver:
Omole IC. Crosslinked polyimide hollow fiber membranes for aggressive natural gas feed streams. [Internet] [Doctoral dissertation]. Georgia Tech; 2008. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/26591.
Council of Science Editors:
Omole IC. Crosslinked polyimide hollow fiber membranes for aggressive natural gas feed streams. [Doctoral Dissertation]. Georgia Tech; 2008. Available from: http://hdl.handle.net/1853/26591
Georgia Tech
2.
Singh, Lovejeet.
Effect of Nanoscale Confinement on the Physical Properties of Polymer Thin Films.
Degree: PhD, Chemical Engineering, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/4822
► The behavior of polymeric systems confined into thin films is a situation that has numerous practical consequences. One particular application in which the properties of…
(more)
▼ The behavior of polymeric systems confined into thin films is a situation that has numerous practical consequences. One particular application in which the properties of thin polymer films is becoming crucially important is in the design, formulation, and processing of photoresists for semiconductor microlithography. As devices continue to be scaled down into the nano-regime, the microelectronics industry will ultimately rely upon a molecular understanding of materials for process development. The majority of these devices are now confined in planar geometries; thus, thin films have played an ever-increasing role in manufacturing of modern electronic devices. This movement towards thinner resist films creates larger surface to volume ratios, and hence thin films can exhibit thermodynamic, structural, and dynamic properties that are different from those of the bulk material. It is thus extremely important to understand the properties of polymers when confined in such geometries for various applications including resists for lithographic patterning. In present work, the influence of a variety of factors including film thickness, molecular weight, and substrate interactions on the polymer thin film physical properties such as the glass transition temperature, coefficient of thermal expansion, dissolution rate, and diffusion coefficient was studied in detail using a combination of experimental characterization and molecular modeling simulation techniques.
Advisors/Committee Members: Dr. Clifford L. Henderson (Committee Chair), Dr. Peter J. Ludovice (Committee Co-Chair), Dr. Carson J. Meredith (Committee Member), Dr. Laren Tolbert (Committee Member), Dr. William J. Koros (Committee Member).
Subjects/Keywords: Diffusion coefficient; Glass transition temperature; Polymer thin films; Thin films; Polymers; Glass transition temperature; Diffusion
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APA (6th Edition):
Singh, L. (2004). Effect of Nanoscale Confinement on the Physical Properties of Polymer Thin Films. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/4822
Chicago Manual of Style (16th Edition):
Singh, Lovejeet. “Effect of Nanoscale Confinement on the Physical Properties of Polymer Thin Films.” 2004. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/4822.
MLA Handbook (7th Edition):
Singh, Lovejeet. “Effect of Nanoscale Confinement on the Physical Properties of Polymer Thin Films.” 2004. Web. 20 Jan 2021.
Vancouver:
Singh L. Effect of Nanoscale Confinement on the Physical Properties of Polymer Thin Films. [Internet] [Doctoral dissertation]. Georgia Tech; 2004. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/4822.
Council of Science Editors:
Singh L. Effect of Nanoscale Confinement on the Physical Properties of Polymer Thin Films. [Doctoral Dissertation]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/4822
Georgia Tech
3.
Ozkan, Ibrahim Ali.
Thermodynamic model for associating polymer solutions.
Degree: PhD, Chemical Engineering, 2004, Georgia Tech
URL: http://hdl.handle.net/1853/5115
► Polymer solutions in which there are strong specific interactions between the polymer and the solvent are of interest in a number of biological applications. Of…
(more)
▼ Polymer solutions in which there are strong specific interactions between the polymer and the solvent are of interest in a number of biological applications. Of particular interest are polymer solutions in which supercritical carbon dioxide (CO2) is the solvent, because polymer processing with CO2 is an important application of green chemistry. Unfortunately, experimental data on the phase behavior of polymer - CO2 systems are relatively scarce, as are models that describe the phase behavior of such systems. The focus of this research is therefore on developing a thermodynamic model based on lattice theory for calculating phase behavior of high pressure polymer solutions with specific intermolecular interactions.
A new model, termed the LELAC (Lattice-based Extended Liquid Activity Coefficient) model is proposed based on the gART-L model of Sukhadia and Variankaval. The new model incorporates the compressibility effect at high pressures. The parameters of the model are (1) the equilibrium constant for association between a polymer segment and a solvent, (2) the specific interaction energy between a polymer segment and a solvent, and (3) the dispersion interaction energy. The dispersion interaction energy is calculated using Regular Solution Theory and therefore depends on the pure component properties. One or both of the remaining parameters is obtained from independent measurements such as FT- IR spectra. Alternatively, the two parameters can be obtained by fitting data.
Cloud point curves of polymer - CO2 systems have been successfully correlated (1.3 % error) with the new model. Also, using fitted parameters from cloud point data, the sorption behavior of CO2 in polymers has been predicted. The polymer investigated include PBMA, PVAc and Polyacrylates. Comparison of cloud points with those obtained using the SAFT model revealed that the new model performs better than the SAFT model (3.6% error) with two adjustable parameters.
The use of FT-IR to investigate interactions between CO2 and a number of polymers has been studied. The results confirm that complexes are formed between CO2 and PMMA, PEMA, PBMA, PVMK, and PVAc. A complex of PVC and CO2 is reported and a new mechanism involving a carbon oxygen triple bond is postulated for this system.
Advisors/Committee Members: Dr. Amyn S. Teja (Committee Chair), Dr. J. Carson Meredith (Committee Member), Dr. Peter J. Ludovice (Committee Member), Dr. Thomas H. Sanders (Committee Member), Dr. William J. Koros (Committee Member).
Subjects/Keywords: Modeling; Association; Polymer solutions; Thermodynamics; Thermochemistry; Polymer solutions; Chemical models
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APA (6th Edition):
Ozkan, I. A. (2004). Thermodynamic model for associating polymer solutions. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/5115
Chicago Manual of Style (16th Edition):
Ozkan, Ibrahim Ali. “Thermodynamic model for associating polymer solutions.” 2004. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/5115.
MLA Handbook (7th Edition):
Ozkan, Ibrahim Ali. “Thermodynamic model for associating polymer solutions.” 2004. Web. 20 Jan 2021.
Vancouver:
Ozkan IA. Thermodynamic model for associating polymer solutions. [Internet] [Doctoral dissertation]. Georgia Tech; 2004. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/5115.
Council of Science Editors:
Ozkan IA. Thermodynamic model for associating polymer solutions. [Doctoral Dissertation]. Georgia Tech; 2004. Available from: http://hdl.handle.net/1853/5115
Georgia Tech
4.
Bhandari, Dhaval Ajit.
Hollow fiber sorbents for the desulfurization of pipeline natural gas.
Degree: PhD, Chemical Engineering, 2010, Georgia Tech
URL: http://hdl.handle.net/1853/42838
► Pipeline natural gas is the primary fuel of choice for distributed fuel cell-based applications. The concentration of sulfur in odorized natural gas is about 30…
(more)
▼ Pipeline natural gas is the primary fuel of choice for distributed fuel cell-based applications. The concentration of sulfur in odorized natural gas is about 30 ppm, with acceptable levels being <1 ppm for catalyst stability in such applications. Packed bed technology for desulfurization suffers from several disadvantages including high pressure drop and slow regeneration rates that require large unit sizes.
We describe a novel Rapid Temperature Swing Adsorption (RTSA) system utilizing hollow fibers with polymer 'binder', impregnated with high loadings of sulfur selective sorbent 'fillers'. Steam and cooling water can be utilized to thermally swing the sorbent during the regeneration cycles. An impermeable, thin polymer barrier layer on the outside of fiber sorbents allows only thermal interactions with the regeneration media, thereby promoting consistent sorption capacity over repeated cycles. A simplified flow pattern minimizes pressure drop, porous core morphology maximizes sorption efficiencies, while small fiber dimensions allows for rapid thermal cycles.
Advisors/Committee Members: Dr. William J. Koros (Committee Chair), Dr. Christopher Jones (Committee Member), Dr. James Stevens (Committee Member), Dr. Pradeep Agrawal (Committee Member), Dr. Ronald Rousseau (Committee Member), Dr. Satish Kumar (Committee Member).
Subjects/Keywords: Membranes; Natural gas; Separations; Porous media; Zeolites; Desulfurization; Adsorbents; Sorbents; Adsorption; Separation (Technology); Porous materials
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APA (6th Edition):
Bhandari, D. A. (2010). Hollow fiber sorbents for the desulfurization of pipeline natural gas. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/42838
Chicago Manual of Style (16th Edition):
Bhandari, Dhaval Ajit. “Hollow fiber sorbents for the desulfurization of pipeline natural gas.” 2010. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/42838.
MLA Handbook (7th Edition):
Bhandari, Dhaval Ajit. “Hollow fiber sorbents for the desulfurization of pipeline natural gas.” 2010. Web. 20 Jan 2021.
Vancouver:
Bhandari DA. Hollow fiber sorbents for the desulfurization of pipeline natural gas. [Internet] [Doctoral dissertation]. Georgia Tech; 2010. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/42838.
Council of Science Editors:
Bhandari DA. Hollow fiber sorbents for the desulfurization of pipeline natural gas. [Doctoral Dissertation]. Georgia Tech; 2010. Available from: http://hdl.handle.net/1853/42838
Georgia Tech
5.
Janakat, Malina Elizabeth.
Synergistic Approach to Exploration of the Microstructure of Novel, Tunable Solvents for Reactions, Separations and Catalyst Recycle.
Degree: PhD, Chemical Engineering, 2006, Georgia Tech
URL: http://hdl.handle.net/1853/10461
► Gas-expanded liquids (GXLs) are a new and benign class of pressure-tunable liquid solvents which show tremendous promise as the next sustainable processing medium. In order…
(more)
▼ Gas-expanded liquids (GXLs) are a new and benign class of pressure-tunable liquid solvents which show tremendous promise as the next sustainable processing medium. In order to realize the potential of GXLs fully, it is necessary to elucidate their cybotactic region and gain an understanding of where properties are different in the bulk and micro-scales and how local structure and order affect both reactions and separations. This work explores the cybotactic region of GXLs and probes the existence and implications of those differences.
This study is started by exploring the cybotactic region of ambient liquid mixtures. Thermodynamic models based on intermolecular forces are used to predict the solubility of multi-functional solids in a variety of solvent mixtures. While this part does not lend any insight into GXLs directly, it acts as a stepping stone in both understanding the intermolecular forces that govern the cybotactic region and by opening the gateway to studying solid solubility in GXLs.
The rest of the study focuses on the differences between bulk and local properties of GXLs. Different probes of polarity in the cybotactic region are compared and the solute dependence of the local structure is explored. Bulk transport properties are measured with different probes in an effort to see if molecular interactions play a role in governing diffusion processes in GXLs.
Advisors/Committee Members: Dr. Charles A. Eckert (Committee Chair), Dr. Charles L. Liotta (Committee Co-Chair), Dr. Amyn Teja (Committee Member), Dr. Rigoberto Hernandez (Committee Member), Dr. William J. Koros (Committee Member).
Subjects/Keywords: Gas-expanded liquids; Cybotactic region
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APA (6th Edition):
Janakat, M. E. (2006). Synergistic Approach to Exploration of the Microstructure of Novel, Tunable Solvents for Reactions, Separations and Catalyst Recycle. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/10461
Chicago Manual of Style (16th Edition):
Janakat, Malina Elizabeth. “Synergistic Approach to Exploration of the Microstructure of Novel, Tunable Solvents for Reactions, Separations and Catalyst Recycle.” 2006. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/10461.
MLA Handbook (7th Edition):
Janakat, Malina Elizabeth. “Synergistic Approach to Exploration of the Microstructure of Novel, Tunable Solvents for Reactions, Separations and Catalyst Recycle.” 2006. Web. 20 Jan 2021.
Vancouver:
Janakat ME. Synergistic Approach to Exploration of the Microstructure of Novel, Tunable Solvents for Reactions, Separations and Catalyst Recycle. [Internet] [Doctoral dissertation]. Georgia Tech; 2006. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/10461.
Council of Science Editors:
Janakat ME. Synergistic Approach to Exploration of the Microstructure of Novel, Tunable Solvents for Reactions, Separations and Catalyst Recycle. [Doctoral Dissertation]. Georgia Tech; 2006. Available from: http://hdl.handle.net/1853/10461
Georgia Tech
6.
Sormana, Joe-Lahai.
Combinatorial Synthesis and High-Throughput Characterization of Polyurethaneureas and Their Nanocomposites with Laponite.
Degree: PhD, Chemical Engineering, 2005, Georgia Tech
URL: http://hdl.handle.net/1853/11640
► Segmented polyurethaneureas (SPUU) are thermoplastic elastomers with excellent elastic properties, high abrasion resistance and tear strength, making them very useful in numerous industrial applications ranging…
(more)
▼ Segmented polyurethaneureas (SPUU) are thermoplastic elastomers with excellent elastic properties, high abrasion resistance and tear strength, making them very useful in numerous industrial applications ranging from microelectronics (slurry pad) to biomedical (artificial heart vessels) applications. The elastic and mechanical properties of these materials are strongly influenced by their two phase morphology. The factors that influence phase separation include difference in polarity between the hard and soft phases, composition and temperature. In general good phase separation results in materials with superior mechanical and elastic properties. Due to the immense potential applications of SPUU elastomers, there is a need for materials with higher strength. However, higher strength is not desired at the detriment of elasticity. If fact, stronger materials with enhanced elasticity are desired. In this thesis, high-strength SPUU elastomers were synthesized by incorporating reactive Laponite particles with surface-active free amine. The synthesis of pure SPUU is very complex, and addition of a reactive silicate further increases the complexity. To remedy this challenge, combinatorial methods and high-throughput screening techniques were used to optimize the diamine concentration and cure temperature. It was determined that pure SPUU elastomers prepared at a diamine stoichiometry of 85 100 mole %, and cured at 90 95 °C produced materials with higher strength and elongation at break. SPUU nanocomposites were prepared by maintaining the overall diamine stoichiometry at 95 mole %, and cured at 90 °C. Uniaxial tensile strength was optimized at a particle weight fraction of 1 wt. %, with a nearly 200 % increase in tensile strength and a 40 % increase in elongation at break, compared to pristine SPUU.
Advisors/Committee Members: Dr. J. Carson Meredith (Committee Chair), Dr. F. Joseph Schork (Committee Member), Dr. Mohan Srinivasarao (Committee Member), Dr. Peter J. Ludovice (Committee Member), Dr. William J. Koros (Committee Member).
Subjects/Keywords: Combinatorial; High throughput; Polyurethaneurea; Mechanical properties; Combinatorial analysis; Elastomers; Elastoplasticity; Materials science; Polyurethanes; Nanocomposites
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APA (6th Edition):
Sormana, J. (2005). Combinatorial Synthesis and High-Throughput Characterization of Polyurethaneureas and Their Nanocomposites with Laponite. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/11640
Chicago Manual of Style (16th Edition):
Sormana, Joe-Lahai. “Combinatorial Synthesis and High-Throughput Characterization of Polyurethaneureas and Their Nanocomposites with Laponite.” 2005. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/11640.
MLA Handbook (7th Edition):
Sormana, Joe-Lahai. “Combinatorial Synthesis and High-Throughput Characterization of Polyurethaneureas and Their Nanocomposites with Laponite.” 2005. Web. 20 Jan 2021.
Vancouver:
Sormana J. Combinatorial Synthesis and High-Throughput Characterization of Polyurethaneureas and Their Nanocomposites with Laponite. [Internet] [Doctoral dissertation]. Georgia Tech; 2005. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/11640.
Council of Science Editors:
Sormana J. Combinatorial Synthesis and High-Throughput Characterization of Polyurethaneureas and Their Nanocomposites with Laponite. [Doctoral Dissertation]. Georgia Tech; 2005. Available from: http://hdl.handle.net/1853/11640
Georgia Tech
7.
Hillock, Alexis Maureen Wrenn.
Crosslinkable Polyimide Mixed Matrix Membranes for Natural Gas Purification.
Degree: PhD, Chemical Engineering, 2005, Georgia Tech
URL: http://hdl.handle.net/1853/13933
► Crosslinkable mixed matrix membranes represent an attractive technology that promises both outstanding separation properties and swelling resistance for the purification of natural gas. This approach…
(more)
▼ Crosslinkable mixed matrix membranes represent an attractive technology that promises both outstanding separation properties and swelling resistance for the purification of natural gas. This approach relies upon dispersal of a CO2/CH4 size-discriminating zeolite in a crosslinkable polymer, which is resistant to CO2 swelling when crosslinked. The resulting membrane has the potential to separate CO2 from CH4 more effectively than traditional pure polymer membranes, while also providing needed membrane stability in the presence of aggressive CO2-contaminated natural gas streams. Control studies are conducted using the pure crosslinkable polymer to observe the separation properties and swelling resistance. Initial crosslinkable mixed matrix membrane experiments are then performed and result in an increase in membrane productivity, instead of the expected increase in selectivity. Traditionally, this is caused by material incompatibility at the polymer/zeolite interface, so the crosslinkable mixed matrix membranes are characterized to examine this issue. During the material characterization, a new non-ideal transport phenomenon is discovered in the zeolite phase. A model is developed to better understand the transport and predict subsequent experimental results. Once the independent materials are proven to be viable, crosslinkable mixed matrix membranes that show enhancements in both efficiency and productivity and exhibit stability in the presence of aggressive CO2 feeds are created.
Advisors/Committee Members: Dr. William J. Koros (Committee Chair), Dr. Christopher W. Jones (Committee Member), Dr. Haskell W. Beckham (Committee Member), Dr. Ronald W. Rousseau (Committee Member), Dr. Stephen J. Miller (Committee Member).
Subjects/Keywords: Crosslinked polyimide; Gas separation; Natural gas purification; Zeolite mesoporosity; Mixed matrix
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APA (6th Edition):
Hillock, A. M. W. (2005). Crosslinkable Polyimide Mixed Matrix Membranes for Natural Gas Purification. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/13933
Chicago Manual of Style (16th Edition):
Hillock, Alexis Maureen Wrenn. “Crosslinkable Polyimide Mixed Matrix Membranes for Natural Gas Purification.” 2005. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/13933.
MLA Handbook (7th Edition):
Hillock, Alexis Maureen Wrenn. “Crosslinkable Polyimide Mixed Matrix Membranes for Natural Gas Purification.” 2005. Web. 20 Jan 2021.
Vancouver:
Hillock AMW. Crosslinkable Polyimide Mixed Matrix Membranes for Natural Gas Purification. [Internet] [Doctoral dissertation]. Georgia Tech; 2005. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/13933.
Council of Science Editors:
Hillock AMW. Crosslinkable Polyimide Mixed Matrix Membranes for Natural Gas Purification. [Doctoral Dissertation]. Georgia Tech; 2005. Available from: http://hdl.handle.net/1853/13933
Georgia Tech
8.
Imler, Stacy Marie.
In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant Stimuli.
Degree: PhD, Mechanical Engineering, 2005, Georgia Tech
URL: http://hdl.handle.net/1853/7281
► The meniscus is a soft, fibrocartilaginous tissue critical for the maintenance of normal knee biomechanics, providing shock absorbance and overall joint lubrication and stability. The…
(more)
▼ The meniscus is a soft, fibrocartilaginous tissue critical for the maintenance of normal knee biomechanics, providing shock absorbance and overall joint lubrication and stability. The adult tissue is highly avascular with a poor autonomous repair capacity in response to injury. Despite the estimated 850,000 arthroscopic surgeries performed per year to repair torn menisci and the increasing evidence showing a high incidence of meniscal degeneration during very early stages of osteoarthritis, little is currently known of the responses of meniscal fibrochondrocytes to physiological stimuli. Therefore, this work explored the responses of meniscal fibrochondrocytes to exogenous biomechanical and biochemical stimuli in an effort to better understand the sensitivity of these cells in their native tissue matrix as well as in a 3-D scaffold environment.
Using the immature bovine model, the changes in biosynthesis of fibrochondrocytes in tissue explants and in an agarose scaffold due to unconfined oscillatory compression were explored. This biomechanical stimulus, previously identified to stimulate matrix production of chondrocytes of articular cartilage, stimulated total protein synthesis in both culture environments. In contrast, the synthesis of proteoglycans, matrix components important in mechanical stiffness and hydration of the tissue, was not affected by these compression protocols. However, the use of a biochemical stimulus in the form of anabolic cytokines significantly enhanced both protein and proteoglycan synthesis as a function of culture environment as well as type of cytokine used. The superposition of oscillatory compression in addition to the use of these potent biochemical stimulators, insulin-like growth factor-I or transforming growth factor-beta 1, did not further enhance matrix synthesis of fibrochondrocytes in agarose culture, suggesting an insensitivity of the fibrochondrocytes to biomechanical stimuli during early stages of matrix maturation within the agarose scaffold. As a combination of biomechanical and biochemical stimuli are responsible for directing the development, maintenance, and repair of the tissue, these findings aid in understanding fibrocartilage maintenance through studying responses in a tissue explant model. Additionally, studying agarose scaffolds aid in the understanding fibrocartilage development and deposition of a de novo matrix.
Advisors/Committee Members: Dr. Marc E. Levenston (Committee Chair), Dr. Christopher S. Lynch (Committee Member), Dr. Lawrence J. Bonassar (Committee Member), Dr. Robert E. Guldberg (Committee Member), Dr. William J. Koros (Committee Member).
Subjects/Keywords: Oscillatory compression; Fibrocartilage; Growth factors; Static compression
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APA (6th Edition):
Imler, S. M. (2005). In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant Stimuli. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/7281
Chicago Manual of Style (16th Edition):
Imler, Stacy Marie. “In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant Stimuli.” 2005. Doctoral Dissertation, Georgia Tech. Accessed January 20, 2021.
http://hdl.handle.net/1853/7281.
MLA Handbook (7th Edition):
Imler, Stacy Marie. “In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant Stimuli.” 2005. Web. 20 Jan 2021.
Vancouver:
Imler SM. In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant Stimuli. [Internet] [Doctoral dissertation]. Georgia Tech; 2005. [cited 2021 Jan 20].
Available from: http://hdl.handle.net/1853/7281.
Council of Science Editors:
Imler SM. In Vitro Modulation of Meniscus Biosynthesis: a Basis for Understanding Cellular Response to Physiologically Relevant Stimuli. [Doctoral Dissertation]. Georgia Tech; 2005. Available from: http://hdl.handle.net/1853/7281
. 
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