subject:(catechol)

1. Wang, Yuhe. A COMPUTATIONAL STUDY OF KETO-ENOL EQUILIBRIA OF CATECHOL IN GAS AND AQUEOUS SOLUTION PHASE.

Degree: 2009, Wake Forest University

► Keto-enol equilibria in catechol have been studied using ab initio methods and first principle density functional theory. Six structural isomers of C6H6O2 were fully optimized… (more)

Subjects/Keywords: CATECHOL

…catechol-H 2 O cluster �� .81 26 IR spectra of 1-a, 1-b and 1-c, respectively… …82 27 Six isomers of catechol-(H 2 O) 2 cluster �� .84 28 IR… …catechol-(H 2 O) 3 cluster �� …...88 30 IR spectra of 3-a, 3-b, 3-c, 3-d, 3… …e, respectively �� .89 vi Abstract Keto-enol equilibria in catechol have been… …vibrational spectra, structural data, and constant pressure heat capacity of catechol with…

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APA (6^th Edition):

Wang, Y. (2009). A COMPUTATIONAL STUDY OF KETO-ENOL EQUILIBRIA OF CATECHOL IN GAS AND AQUEOUS SOLUTION PHASE. (Thesis). Wake Forest University. Retrieved from http://hdl.handle.net/10339/14776

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wang, Yuhe. “A COMPUTATIONAL STUDY OF KETO-ENOL EQUILIBRIA OF CATECHOL IN GAS AND AQUEOUS SOLUTION PHASE.” 2009. Thesis, Wake Forest University. Accessed January 22, 2021. http://hdl.handle.net/10339/14776.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wang, Yuhe. “A COMPUTATIONAL STUDY OF KETO-ENOL EQUILIBRIA OF CATECHOL IN GAS AND AQUEOUS SOLUTION PHASE.” 2009. Web. 22 Jan 2021.

Vancouver:

Wang Y. A COMPUTATIONAL STUDY OF KETO-ENOL EQUILIBRIA OF CATECHOL IN GAS AND AQUEOUS SOLUTION PHASE. [Internet] [Thesis]. Wake Forest University; 2009. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10339/14776.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wang Y. A COMPUTATIONAL STUDY OF KETO-ENOL EQUILIBRIA OF CATECHOL IN GAS AND AQUEOUS SOLUTION PHASE. [Thesis]. Wake Forest University; 2009. Available from: http://hdl.handle.net/10339/14776

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Rhodes University

2. Ayeni, Ayowole Olaolu. Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol.

Degree: Faculty of Science, Chemistry, 2018, Rhodes University

URL: http://hdl.handle.net/10962/62339

► The study focused on the design of new Cu(II) and Fe(III) complexes, with or without thiocyanate (NCS-), as possible candidates of catechol oxidation using 3,5-di-tert-butyl… (more)

▼ The study focused on the design of new Cu(II) and Fe(III) complexes, with or without thiocyanate (NCS-), as possible candidates of catechol oxidation using 3,5-di-tert-butyl catechol (3,5-DTBC) as substrate. Two classes of Mannich bases were studied depending on the active methylene group from which they were formed, being either p-cresol or acetaminophen. The ligands were characterised by 1H and 13C NMR spectroscopy. Crystal structures of three of the ligands are newly reported, along with detailed discussion of polymorphism observed in one of the ligands, and the nature of the hydrogen within the ligands in the solid state as well as in solution. The Mannich bases behaved as bidentate (NO), tridentate (NNO) and tetradentate (NNOO) ligands on coordination to Cu(II) and Fe(III) ions in which the hydroxyl group may be protonated or deprotonated. Coordination was determined by IR spectroscopy, investigating shifts in vOH, vC-O and in vCNC of the Mannich bases. The vCNC stretching frequencies v1 and v2 of asymmetrical piperazine Mannich bases were observed to shift upward in few cases upon complexation and this is attributed to (chair-boat) conformational change. The mode of coordination of the thiocyanate was determined by IR spectroscopy. Of the forty metal complexes investigated, six groups of metal complexes were identified as follows: (i) Ma(Ln)aClb-cH2O; (ii) Ma(HLn)a(NCS)aClb; (iii) Ma(Ln)a(NCS)aClb; (iv) Ma(HLn)aClb-cH2O; (v) Ma(Ln)a(NCS)a-cH2O; (vi) Ma(HLn)a(NCS)a-cH2O where a = 1 - 2 ; b = 1 - 4, c = 1 - 8. Molar conductivity values of 4.38 - 161.77 Q-1.cm2.mol-1 for the Cu(II) and Fe(III) complexes in DMSO showed that they range from non-electrolytes to 1:1 and 1:2 electrolytes. Electronic spectra for the ligands and the complexes were conducted in DMF and DMSO. The ligands are characterised by and n→n* and n→n* transitions. Intraligand charge transfer transitions peculiar to the nitro group were observed at about 430 nm for the nitro containing ligands. On coordination, these bands overshadowed the d-d transitions particularly for the nitro-Mannich bases. On complexation, ligand to metal charge transfer transitions associated with the hydroxyl were observed between 320 - 420 nm. Charge transfer transitions associated with the thiocyanates were also observed and discussed. The d-d transitions for high spin Fe(III) complexes are spin forbidden and generally uninformative. Those of Cu(II) are spin allowed and allow tentative structural proposals. Square planar and octahedral geometry are generally prevalent in the Cu(II) complexes with trigonal bipyramidal observed in few instances. The Fe(III) complexes are generally octahedral. Thirty-nine of the forty synthesised Cu(II) and Fe(III) complexes were catalytically active on the substrate (3,5-DTBC) in DMF with turnover rates (kcat) reported in the range of 1.86 ± 0.09 to 112.32 ± 3.72 h-1. From this pool of complexes, sixteen isostructural pairs were identified in terms of geometry, molecular formula and the source of the Mannich base and the following…

Subjects/Keywords: Mannich bases; Catechol; Catechol – Oxidation; Thiocyanates; Catalysts

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APA (6^th Edition):

Ayeni, A. O. (2018). Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol. (Thesis). Rhodes University. Retrieved from http://hdl.handle.net/10962/62339

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ayeni, Ayowole Olaolu. “Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol.” 2018. Thesis, Rhodes University. Accessed January 22, 2021. http://hdl.handle.net/10962/62339.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ayeni, Ayowole Olaolu. “Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol.” 2018. Web. 22 Jan 2021.

Vancouver:

Ayeni AO. Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol. [Internet] [Thesis]. Rhodes University; 2018. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10962/62339.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ayeni AO. Mannich base metal complexes and their thiocyanate analogues as catalysts in the oxidation of Catechol. [Thesis]. Rhodes University; 2018. Available from: http://hdl.handle.net/10962/62339

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Zambia

3. Mutondo, Moola Siseho. The characterisation of acetophenone monooxygenase .

Degree: 2011, University of Zambia

URL: http://hdl.handle.net/123456789/276

► Catechols are important precursors in the production of pharmaceuticals but they are associated with many problems such as their instability and susceptibility to oxidation and… (more)

▼ Catechols are important precursors in the production of pharmaceuticals but they are associated with many problems such as their instability and susceptibility to oxidation and polymerisation. In order to avoid these problems, acylcatechols are used. However, disadvantages exist in the industrial production of acylcatechols. The production of acylcatechols industrially involves chemical syntheses that require large amounts of hazardous peracids, and accumulation of large amounts of undesirable byproducts. The processes used also have low yields. A solution to these problems associated with the production of acylcatechols lies in the use of biocatalytic means of synthesising acylcatechols. Baeyer-Villiger monooxygenases (BVMOs) have been found to have the ability to yield key chiral products of value in various chemoenzymatic syntheses used in industry. This study investigates the potential of the BVMOs to synthesise acylcatechols thereby avoiding the use of complex and hazardous procedures. Preliminary screening of the ability of various bacteria to perform Baeyer-Villiger oxidations to produce acylcatechols showed that Pseudomonas fluorescens ACB and Arthrobacter sp. M5 have notable potential to catalyse such reactions. In this study, the acetophenone monooxygenase produced by Arthrobacter sp. M5 was selected for further investigation. The acetophenone monooxygenase gene was cloned in Escherichia coli HB101 in order to enable sequence analysis studies of the gene. This also facilitated greater manipulation of the gene in a host (E. coli) that is well studied and easy to apply in the overexpression of the acetophenone monooxygenase gene. Overexpression of the acetophenone monooxygenase gene is necessary because it allows for greater amounts of the acetophenone monooxygenase to be produced for optimisation studies that enable the enzyme to be tailored to the needs of industry. After optimisation, the acetophenone monooxygenase can be used to biocatalytically produce valuable acylcatechols thus avoiding the drawbacks associated with chemical syntheses. A library of Arthrobacter sp. M5 total DNA was made in E. coli HB101 and was screened for Baeyer-Villiger monooxygenase activity using two colorimetric methods. The library was also screened using degenerate probes by Southern blotting.

Subjects/Keywords: catechol; Monooxygenase; Phenacetin

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APA (6^th Edition):

Mutondo, M. S. (2011). The characterisation of acetophenone monooxygenase . (Thesis). University of Zambia. Retrieved from http://hdl.handle.net/123456789/276

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mutondo, Moola Siseho. “The characterisation of acetophenone monooxygenase .” 2011. Thesis, University of Zambia. Accessed January 22, 2021. http://hdl.handle.net/123456789/276.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mutondo, Moola Siseho. “The characterisation of acetophenone monooxygenase .” 2011. Web. 22 Jan 2021.

Vancouver:

Mutondo MS. The characterisation of acetophenone monooxygenase . [Internet] [Thesis]. University of Zambia; 2011. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/123456789/276.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mutondo MS. The characterisation of acetophenone monooxygenase . [Thesis]. University of Zambia; 2011. Available from: http://hdl.handle.net/123456789/276

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Mississippi State University

4. De Silva, Nuwan Dileepa. Synthesis, characterization, and catalytic activity of silica supported bimetallic copper catalysts for organic oxidation reactions and the study of benzylation of triketones.

Degree: PhD, Chemistry, 2013, Mississippi State University

URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-07292013-010516/ ;

► The dissertation describes research work on development of bimetallic heterogeneous catalysts for oxidation of organic compounds. Binuclear metal complexes are an interesting class of… (more)

▼ The dissertation describes research work on development of bimetallic heterogeneous catalysts for oxidation of organic compounds. Binuclear metal complexes are an interesting class of compounds due to their catalytic activity. The approach involves anchoring a triketone ligand to Cab-O-Sil via a linker. Specifically, silica gel was allowed to react with p-chloromethylphenyltrimethoxysilane followed by coupling with deprotonated triketone compounds. The viability of this approach was verified by performing the benzylation reaction of triketones with benzyl halides under basic conditions. The benzylation of 2,4,6-heptanetrione and 1,5-diphenyl-1,3,5-pentanetrione is achieved with benzyl bromide using n-tetrabutylammonium fluoride as base. These benzylation reaction conditions were used to attach the triketones to the surface-attached linker. Once the ligand is attached to the silica gel, the catalyst is formed by coordinating two copper(II) ions from solution to the deprotonated triketone. The coordination of copper(II) ions to the triketone was monitored using UV-vis spectroscopy. The modified silica gel is characterized by diffuse reflectance infrared Fourier spectroscopy (DRIFTS), and thermal gravimetric analysis (TGA) at the different stages of catalyst formation. All techniques indicated significant attachment of linker and triketone to the support. The oxidation of 3,5-di-tert-butyl catechol (DTBC) and benzyl alcohol was carried out under aerobic conditions using these catalysts. The kinetics of the DTBC oxidation and benzyl alcohol oxidation was studied using bimetallic and monometallic catalytic systems. The copper complexes of the triketone ligands were also evaluated as catalysts for the oxidation of DTBC. New bimetallic metal complexes with triketone ligands having a benzyl group were synthesized and characterized by high resolution mass spectroscopy and IR spectroscopy. In addition to a detailed description of the synthesis and characterization of new triketone compounds, and the heterogeneous catalyst systems, a comparison of the kinetics of the oxidation of DTBC using these catalysts will be discussed. Advisors/Committee Members: William P. Henry (chair), David O. Wipf (committee member), Andrzej Sygula (committee member), Joseph Emerson (committee member), Dongmao Zhang (committee member).

Subjects/Keywords: benzylation; catechol; bimetallic

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APA (6^th Edition):

De Silva, N. D. (2013). Synthesis, characterization, and catalytic activity of silica supported bimetallic copper catalysts for organic oxidation reactions and the study of benzylation of triketones. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-07292013-010516/ ;

Chicago Manual of Style (16^th Edition):

De Silva, Nuwan Dileepa. “Synthesis, characterization, and catalytic activity of silica supported bimetallic copper catalysts for organic oxidation reactions and the study of benzylation of triketones.” 2013. Doctoral Dissertation, Mississippi State University. Accessed January 22, 2021. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07292013-010516/ ;.

MLA Handbook (7^th Edition):

De Silva, Nuwan Dileepa. “Synthesis, characterization, and catalytic activity of silica supported bimetallic copper catalysts for organic oxidation reactions and the study of benzylation of triketones.” 2013. Web. 22 Jan 2021.

Vancouver:

De Silva ND. Synthesis, characterization, and catalytic activity of silica supported bimetallic copper catalysts for organic oxidation reactions and the study of benzylation of triketones. [Internet] [Doctoral dissertation]. Mississippi State University; 2013. [cited 2021 Jan 22]. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-07292013-010516/ ;.

Council of Science Editors:

De Silva ND. Synthesis, characterization, and catalytic activity of silica supported bimetallic copper catalysts for organic oxidation reactions and the study of benzylation of triketones. [Doctoral Dissertation]. Mississippi State University; 2013. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-07292013-010516/ ;

University of Manchester

5. Khan, Mohammad. Synthesis and Sequestrating Properties of Enterochelin Analogues.

Degree: 2019, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:322603

► Acquisition of iron by siderophores is critical for the survival of many microbes. Enterochelin is a catechol siderophore that has a trilactonate macrocylic core derived… (more)

Subjects/Keywords: catechol; siderophores; macrocycle; Enterochelin analogue

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APA (6^th Edition):

Khan, M. (2019). Synthesis and Sequestrating Properties of Enterochelin Analogues. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:322603

Chicago Manual of Style (16^th Edition):

Khan, Mohammad. “Synthesis and Sequestrating Properties of Enterochelin Analogues.” 2019. Doctoral Dissertation, University of Manchester. Accessed January 22, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:322603.

MLA Handbook (7^th Edition):

Khan, Mohammad. “Synthesis and Sequestrating Properties of Enterochelin Analogues.” 2019. Web. 22 Jan 2021.

Vancouver:

Khan M. Synthesis and Sequestrating Properties of Enterochelin Analogues. [Internet] [Doctoral dissertation]. University of Manchester; 2019. [cited 2021 Jan 22]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:322603.

Council of Science Editors:

Khan M. Synthesis and Sequestrating Properties of Enterochelin Analogues. [Doctoral Dissertation]. University of Manchester; 2019. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:322603

University of Saskatchewan

6. Huang, Xiaoyan. Characterization and genome-scale metabolic modeling of catechol-degrading Pseudomonas fluorescens isolated from a petroleum hydrocarbon-impacted site.

Degree: 2020, University of Saskatchewan

URL: http://hdl.handle.net/10388/12813

► Pseudomonas fluorescens is a candidate for efficient petroleum hydrocarbons (PHC) biodegradation. In this work, a P. fluorescens strain was isolated from a local PHC-impacted site.… (more)

▼ Pseudomonas fluorescens is a candidate for efficient petroleum hydrocarbons (PHC) biodegradation. In this work, a P. fluorescens strain was isolated from a local PHC-impacted site. To investigate its PHC biodegradation performance, catechol, an important metabolic intermediate during monoaromatic hydrocarbon biodegradation, was chosen as the sole carbon source. A set of experiments based on a 23 factorial design was undertaken to investigate how nitrate, sulfate, and phosphate ions affect catechol biodegradation by the isolated P. fluorescens strain. The experimental results were subjected to ANOVA. Maximum specific catechol degradation rates (the response) were estimated by a three-parameter logistic model to evaluate bioremediation performance. ANOVA results suggest introducing nitrate ions alone may lead to poorer bioremediation performance, introducing sulfate ions alone does not affect bioremediation performance, but supplementing with nitrate and sulfate ions together can enhance bioremediation performance. P. fluorescens was also shown to survive under sulfur-limited conditions. Injecting phosphate ions also led to better bioremediation performance. To gain extensive and systematic knowledge of P. fluorescens, the first genome-scale metabolic model (GSMM) for P. fluorescens was reconstructed, termed lCW1057. The model was validated by in vitro growth data. The periplasmic compartment was constructed to better represent the proton gradient profile. The reconstructed proton transport chain has a P/O ratio of 11/8. Flux balance analysis (FBA) was performed to simulate the whole-cell metabolic flow. The simulation results suggested the β-ketoadipate pathway is involved in catechol metabolism by P. fluorescens while the uptake of oxygen is mandatory for cleavage of catechol’s aromatic ring. The Entner-Doudoroff (ED) pathway was involved in glycolysis for P. fluorescens. Moreover, nitrates can be used as the terminal electron acceptor to support P. fluorescens growth under anaerobic condition. Advisors/Committee Members: Lin, Yen-Han, Wang, Hui, Xiong, WenHui, Chang, WonJae.

Subjects/Keywords: Bioremediation; Catechol; Pseudomonas fluorescens

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APA (6^th Edition):

Huang, X. (2020). Characterization and genome-scale metabolic modeling of catechol-degrading Pseudomonas fluorescens isolated from a petroleum hydrocarbon-impacted site. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12813

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Huang, Xiaoyan. “Characterization and genome-scale metabolic modeling of catechol-degrading Pseudomonas fluorescens isolated from a petroleum hydrocarbon-impacted site.” 2020. Thesis, University of Saskatchewan. Accessed January 22, 2021. http://hdl.handle.net/10388/12813.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Huang, Xiaoyan. “Characterization and genome-scale metabolic modeling of catechol-degrading Pseudomonas fluorescens isolated from a petroleum hydrocarbon-impacted site.” 2020. Web. 22 Jan 2021.

Vancouver:

Huang X. Characterization and genome-scale metabolic modeling of catechol-degrading Pseudomonas fluorescens isolated from a petroleum hydrocarbon-impacted site. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10388/12813.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Huang X. Characterization and genome-scale metabolic modeling of catechol-degrading Pseudomonas fluorescens isolated from a petroleum hydrocarbon-impacted site. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/12813

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas Southwestern Medical Center

7. Birchfield, Thomas Richard. COMT Genotype, Schizophrenia, and Dopamine Transmission.

Degree: 2011, University of Texas Southwestern Medical Center

URL: http://hdl.handle.net/2152.5/839

► Catechol-o-methyltransferase (COMT) catabolism is the primary mechanism for dopamine signal deactivation in the dorsolateral prefrontal cortex, an area of the brain associated with working memory.… (more)

Subjects/Keywords: Schizophrenia; Dopamine; Catechol O-Methyltransferase

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APA (6^th Edition):

Birchfield, T. R. (2011). COMT Genotype, Schizophrenia, and Dopamine Transmission. (Thesis). University of Texas Southwestern Medical Center. Retrieved from http://hdl.handle.net/2152.5/839

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Birchfield, Thomas Richard. “COMT Genotype, Schizophrenia, and Dopamine Transmission.” 2011. Thesis, University of Texas Southwestern Medical Center. Accessed January 22, 2021. http://hdl.handle.net/2152.5/839.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Birchfield, Thomas Richard. “COMT Genotype, Schizophrenia, and Dopamine Transmission.” 2011. Web. 22 Jan 2021.

Vancouver:

Birchfield TR. COMT Genotype, Schizophrenia, and Dopamine Transmission. [Internet] [Thesis]. University of Texas Southwestern Medical Center; 2011. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2152.5/839.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Birchfield TR. COMT Genotype, Schizophrenia, and Dopamine Transmission. [Thesis]. University of Texas Southwestern Medical Center; 2011. Available from: http://hdl.handle.net/2152.5/839

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University

8. George, Kevin. Adaptation Of Pseudomonas Putida F1 To Growth On Styrene.

Degree: PhD, Environmental Toxicology, 2011, Cornell University

URL: http://hdl.handle.net/1813/33565

► Pseudomonas putida F1 is unable to grow on styrene, a common industrial pollutant, despite degrading it through the toluene degradation (tod) pathway. This dissertation investigates… (more)

▼ Pseudomonas putida F1 is unable to grow on styrene, a common industrial pollutant, despite degrading it through the toluene degradation (tod) pathway. This dissertation investigates the biochemical and genetic aspects of styrene degradation by P. putida F1 and identifies substrate-level catechol-2,3-dioxygenase (C23O) inactivation as the factor which prevents growth on styrene. Novel adaptations to growth on styrene were investigated and found to mitigate C23O inactivation through management of 3-vinylcatechol production and consumption. Previous studies of P. putida F1 identified TodF, a hydrolase responsible for the degradation of styrene meta-fission product (MFP), as putatively responsible for F1's inability to grow on styrene. Through kinetic and growth analyses, we demonstrated that TodF is capable of styrene MFP degradation and thus not responsible for prohibiting growth on styrene. Preliminary genetic analysis of styrene adapted mutants strengthened this conclusion. It was found that cultures of F1 exposed to styrene accumulated 3vinylcatechol in the media, suggestive of inhibited C23O activity. Specifically, micromolar concentrations of 3-vinylcatechol were found to inactivate TodE during catalysis. Analysis of cells growing on styrene suggested that inactivation of TodE and the subsequent accumulation of 3-vinylcatechol resulted in toxicity and cell death. Over-expression of TodE or an inactivation resistant C23O on a plasmid was able to prevent catechol accumulation and confer the ability to grow on styrene. We characterized a spontaneous F1 mutant, designated SF1, which was capable of growth on styrene and did not accumulate 3-vinylcatechol. Resting cell assays demonstrated that the activity of toluene dioxygenase (TDO), the multicomponent enzyme responsible for the production of 3-vinylcatechol from styrene, was reduced in SF1. DNA sequence analysis of the tod operon revealed a single base pair mutation in todA (C479T), a gene encoding the reductase component of TDO. Replacement of the wild-type todA allele in F1 with todAC479T from SF1 reduced TDO activity, prevented 3-vinylcatechol accumulation, and conferred the ability to grow on styrene. Collectively, our data reveals a unique adaptation where slowing down the rate of vinylcatechol production via decreased TDO activity leads to reduced C23O inactivation and permits growth on styrene. Advisors/Committee Members: Hay, Anthony G. (chair), Madsen, Eugene Lewis (committee member), Wilson, David B (committee member).

Subjects/Keywords: Biodegradation; Pseudomonas putida; catechol-2; 3-dioxygenase

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APA (6^th Edition):

George, K. (2011). Adaptation Of Pseudomonas Putida F1 To Growth On Styrene. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/33565

Chicago Manual of Style (16^th Edition):

George, Kevin. “Adaptation Of Pseudomonas Putida F1 To Growth On Styrene.” 2011. Doctoral Dissertation, Cornell University. Accessed January 22, 2021. http://hdl.handle.net/1813/33565.

MLA Handbook (7^th Edition):

George, Kevin. “Adaptation Of Pseudomonas Putida F1 To Growth On Styrene.” 2011. Web. 22 Jan 2021.

Vancouver:

George K. Adaptation Of Pseudomonas Putida F1 To Growth On Styrene. [Internet] [Doctoral dissertation]. Cornell University; 2011. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/1813/33565.

Council of Science Editors:

George K. Adaptation Of Pseudomonas Putida F1 To Growth On Styrene. [Doctoral Dissertation]. Cornell University; 2011. Available from: http://hdl.handle.net/1813/33565

Addis Ababa University

9. Asfaw, Negash. Study of EC mechanism by cyclic voltammetry: Electrochemical oxidation of catechol in the presence of imidazole .

Degree: 2012, Addis Ababa University

URL: http://etd.aau.edu.et/dspace/handle/123456789/503

► Electrochemical oxidation of catechol has been studied in the presence of imidazole as nucleophile in aqueous solution, using cyclic voltammetry. The results indicate the participation… (more)

Subjects/Keywords: catechol and imidazole; cyclic voltammetry; EC mechanism

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APA (6^th Edition):

Asfaw, N. (2012). Study of EC mechanism by cyclic voltammetry: Electrochemical oxidation of catechol in the presence of imidazole . (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/503

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Asfaw, Negash. “Study of EC mechanism by cyclic voltammetry: Electrochemical oxidation of catechol in the presence of imidazole .” 2012. Thesis, Addis Ababa University. Accessed January 22, 2021. http://etd.aau.edu.et/dspace/handle/123456789/503.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Asfaw, Negash. “Study of EC mechanism by cyclic voltammetry: Electrochemical oxidation of catechol in the presence of imidazole .” 2012. Web. 22 Jan 2021.

Vancouver:

Asfaw N. Study of EC mechanism by cyclic voltammetry: Electrochemical oxidation of catechol in the presence of imidazole . [Internet] [Thesis]. Addis Ababa University; 2012. [cited 2021 Jan 22]. Available from: http://etd.aau.edu.et/dspace/handle/123456789/503.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Asfaw N. Study of EC mechanism by cyclic voltammetry: Electrochemical oxidation of catechol in the presence of imidazole . [Thesis]. Addis Ababa University; 2012. Available from: http://etd.aau.edu.et/dspace/handle/123456789/503

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Michigan State University

10. Subramanian, Ramkumar. Kinetics of growth and catechol production by bacillus stearothermophilus.

Degree: MS, Department of Chemical Engineering, 1992, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:24675

Subjects/Keywords: Bacillus stearothermophilus; Catechol

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APA (6^th Edition):

Subramanian, R. (1992). Kinetics of growth and catechol production by bacillus stearothermophilus. (Masters Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:24675

Chicago Manual of Style (16^th Edition):

Subramanian, Ramkumar. “Kinetics of growth and catechol production by bacillus stearothermophilus.” 1992. Masters Thesis, Michigan State University. Accessed January 22, 2021. http://etd.lib.msu.edu/islandora/object/etd:24675.

MLA Handbook (7^th Edition):

Subramanian, Ramkumar. “Kinetics of growth and catechol production by bacillus stearothermophilus.” 1992. Web. 22 Jan 2021.

Vancouver:

Subramanian R. Kinetics of growth and catechol production by bacillus stearothermophilus. [Internet] [Masters thesis]. Michigan State University; 1992. [cited 2021 Jan 22]. Available from: http://etd.lib.msu.edu/islandora/object/etd:24675.

Council of Science Editors:

Subramanian R. Kinetics of growth and catechol production by bacillus stearothermophilus. [Masters Thesis]. Michigan State University; 1992. Available from: http://etd.lib.msu.edu/islandora/object/etd:24675

11. Soares, Rui Filipe Lopes. Biosynthesis of human membrane-bound Catechol-O-methyltransferase.

Degree: 2012, Universidade da Beira Interior

URL: http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/1120

► Catechol-O-methyltransferase (COMT, EC 2.1.1.6) is an S-adenosyl-L-methionine-dependent methyltransferase enzyme that catalyzes the methylation of catechol substrates (catecholamines, catecholestrogens). Physiologically, it is responsible for the elimination… (more)

▼ Catechol-O-methyltransferase (COMT, EC 2.1.1.6) is an S-adenosyl-L-methionine-dependent methyltransferase enzyme that catalyzes the methylation of catechol substrates (catecholamines, catecholestrogens). Physiologically, it is responsible for the elimination of biologically active or toxic catechols, making it a protein with great clinical relevance as therapeutic target in serious disorders, like schizophrenia and Parkinson´s disease. To fulfill pharmaceuticals requirements, new strategies of optimization and large-scale production of COMT enzyme are crucial. Statistical optimization approaches have demonstrated their enormous value in laboratory and industrial scale, namely in biotechnological production processes, in which an incremental enhancement can be a perpetual improvement. In this work, we aimed the optimization of recombinant human membrane-bound COMT (hMBCOMT) enzymatic activity yields following a statistical optimization as a solving approach. Plackett-Burman design was used as a first optimization step to identify which factors have a significant effect in hMBCOMT productivity and activity levels, and Response Surface Methodology (RSM), by a Central Composite Design (CCD), to optimize the process. We applied Brevibacillus choshinensis cells for the biosynthesis of hMBCOMT and a semi-defined medium for cell growth. This medium was subjected to a first screening using the Plackett–Burman design to evaluate the influence of the culture parameters (chemicals and physicals) in hMBCOMT enzymatic activity levels. Enzymatic activity were measured in a high performance liquid chromatography (HPLC) coupled to a coulochemical detector. Among the eleven variables tested, polypeptone, ammonium sulfate, glucose and temperature were selected owing to their significant effect on human MBCOMT enzymatic activity. The biological human MBCOMT activity obtained with the semi-defined medium in Plackett-Burman design were very promising, while were higher than the obtained with 2SYNm medium, a traditional growth medium for Brevibacillus cells of this work. Typically, we obtained values of 93nmol/h for hMBCOMT total enzymatic activity and 30 nmol/h/mg of specific activity with protein in its native form, without the use of any kind of detergents on protein solubilization step. Based on the results of Plackett–Burman design, a CCD was adopted to define optimal components concentration and temperature in order to maximize our response. The CCD model presented a multiple correlation coefficient value of 0.635 and a significant lack of fit, showing the lack aptness of the model to the process optimization and the failure to attain the optimal concentration of each variable.

Subjects/Keywords: Doença de Parkinson; COMT membranar humana; Desenho Plackett-Burman; COMT (Catechol-O-methyltransferase); Proteína Catechol-O-metiltransferase

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APA (6^th Edition):

Soares, R. F. L. (2012). Biosynthesis of human membrane-bound Catechol-O-methyltransferase. (Thesis). Universidade da Beira Interior. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/1120

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Soares, Rui Filipe Lopes. “Biosynthesis of human membrane-bound Catechol-O-methyltransferase.” 2012. Thesis, Universidade da Beira Interior. Accessed January 22, 2021. http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/1120.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Soares, Rui Filipe Lopes. “Biosynthesis of human membrane-bound Catechol-O-methyltransferase.” 2012. Web. 22 Jan 2021.

Vancouver:

Soares RFL. Biosynthesis of human membrane-bound Catechol-O-methyltransferase. [Internet] [Thesis]. Universidade da Beira Interior; 2012. [cited 2021 Jan 22]. Available from: http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/1120.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Soares RFL. Biosynthesis of human membrane-bound Catechol-O-methyltransferase. [Thesis]. Universidade da Beira Interior; 2012. Available from: http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/1120

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Georgia

12. Perez Almeida, Solandre Elvira. Micro-oxygen processing and biochemical deteriorative vectors in bananas and orange juice.

Degree: 2014, University of Georgia

URL: http://hdl.handle.net/10724/26983

► The effect of micro-oxygen (MO) and atmospheric processing on polyphenol oxidase (PPO) in bananas and orange juice quality was evaluated. PPO activity decreased non-linearly with… (more)

Subjects/Keywords: micro-oxygen; PPO; catechol; ascorbic acid; color; dissolved oxygen

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APA (6^th Edition):

Perez Almeida, S. E. (2014). Micro-oxygen processing and biochemical deteriorative vectors in bananas and orange juice. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/26983

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Perez Almeida, Solandre Elvira. “Micro-oxygen processing and biochemical deteriorative vectors in bananas and orange juice.” 2014. Thesis, University of Georgia. Accessed January 22, 2021. http://hdl.handle.net/10724/26983.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Perez Almeida, Solandre Elvira. “Micro-oxygen processing and biochemical deteriorative vectors in bananas and orange juice.” 2014. Web. 22 Jan 2021.

Vancouver:

Perez Almeida SE. Micro-oxygen processing and biochemical deteriorative vectors in bananas and orange juice. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10724/26983.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Perez Almeida SE. Micro-oxygen processing and biochemical deteriorative vectors in bananas and orange juice. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/26983

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Manchester

13. Czarnota, Sylwia. A study of enzymatic methyl transfer catalysed by COMT: mechanism and structural biology.

Degree: 2019, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:318702

► Looking at protein structure and studying changes in active site geometry is a fundamental step to understand how enzymes work, how the reaction proceeds and… (more)

▼ Looking at protein structure and studying changes in active site geometry is a fundamental step to understand how enzymes work, how the reaction proceeds and it gives absolutely essential background for potential drug design and development. Enzymes that transfer methyl groups (methyltransferases, MTs) are exciting targets for therapeutic intervention in a range of disorders. COMT (catechol-O-methyltransferase) is a model system for the study of enzyme-catalysed methyl transfer, but is also a very important drug target, as inhibition of this enzyme is a strategy for the treatment of a range of neurological disorders including Parkinsonâ€™s disease, depression and schizophrenia. This thesis primarily concerns the use of nuclear magnetic resonance (NMR) spectroscopy to study the reactant and transition state analogue (TSA) of human S-COMT. To achieve that, firstly, two NMR backbone assignments of COMT ternary complexes were determined. One with sinefungin, a fungal-derived inhibitor that possesses transition state-like charge on the transferring methyl group; and the second with S-Adenosyl-L-methionine (SAM), which is the major methyl donor for MTs, naturally present in organisms. Two X-ray crystal structures of the same complexes were obtained in high resolution. Comparisons between these complexes were done with the aid of computational studies, identifying subtle conformational differences in the active sites of the two ternary complexes. Results were consistent between all three methods, leading to the conclusion of active site â€œcompactionâ€ and electrostatic stabilization between the transferring methyl group and â€œequatorialâ€ residues that are orthogonal to the donor-acceptor coordinate. High pressure NMR (up to 2500 bar) was next used to probe protein flexibility and rigidity, as well as NMR relaxation measurements, to study dynamics of the backbone. Both indicated high stability of the protein and showed that the majority of the protein is highly ordered. Those methods also indicated C-terminus stabilisation, most likely due to the dimer interface occurring there, which could be the focus of future work. Advisors/Committee Members: SCRUTTON, NIGEL NS, WALTHO, JONATHAN JP, Hay, Sam, Scrutton, Nigel, Waltho, Jonathan.

Subjects/Keywords: enzyme; Catechol-O-methyltransferase; COMT; nuclear magnetic resonance (NMR)

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APA (6^th Edition):

Czarnota, S. (2019). A study of enzymatic methyl transfer catalysed by COMT: mechanism and structural biology. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:318702

Chicago Manual of Style (16^th Edition):

Czarnota, Sylwia. “A study of enzymatic methyl transfer catalysed by COMT: mechanism and structural biology.” 2019. Doctoral Dissertation, University of Manchester. Accessed January 22, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:318702.

MLA Handbook (7^th Edition):

Czarnota, Sylwia. “A study of enzymatic methyl transfer catalysed by COMT: mechanism and structural biology.” 2019. Web. 22 Jan 2021.

Vancouver:

Czarnota S. A study of enzymatic methyl transfer catalysed by COMT: mechanism and structural biology. [Internet] [Doctoral dissertation]. University of Manchester; 2019. [cited 2021 Jan 22]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:318702.

Council of Science Editors:

Czarnota S. A study of enzymatic methyl transfer catalysed by COMT: mechanism and structural biology. [Doctoral Dissertation]. University of Manchester; 2019. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:318702

University of Adelaide

14. Berry, Dorothy Muriel. Studies on monoamine oxidase and catechol-o-methyltransferase in the the isolated artery.

Degree: 1976, University of Adelaide

URL: http://hdl.handle.net/2440/120970

Subjects/Keywords: monoamine oxidase; catechol-o-methyltransferase

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Berry, D. M. (1976). Studies on monoamine oxidase and catechol-o-methyltransferase in the the isolated artery. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/120970

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Berry, Dorothy Muriel. “Studies on monoamine oxidase and catechol-o-methyltransferase in the the isolated artery.” 1976. Thesis, University of Adelaide. Accessed January 22, 2021. http://hdl.handle.net/2440/120970.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Berry, Dorothy Muriel. “Studies on monoamine oxidase and catechol-o-methyltransferase in the the isolated artery.” 1976. Web. 22 Jan 2021.

Vancouver:

Berry DM. Studies on monoamine oxidase and catechol-o-methyltransferase in the the isolated artery. [Internet] [Thesis]. University of Adelaide; 1976. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2440/120970.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Berry DM. Studies on monoamine oxidase and catechol-o-methyltransferase in the the isolated artery. [Thesis]. University of Adelaide; 1976. Available from: http://hdl.handle.net/2440/120970

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

15. Maier, Greg. Catechol-Cation Synergy in Wet Adhesive Materials.

Degree: 2017, University of California – eScholarship, University of California

URL: http://www.escholarship.org/uc/item/42v3x74x

► In physiological fluids and seawater, adhesion of synthetic polymers to solid surfaces is impaired by high salt, pH, and hydration. However, mussels have evolved effective… (more)

▼ In physiological fluids and seawater, adhesion of synthetic polymers to solid surfaces is impaired by high salt, pH, and hydration. However, mussels have evolved effective strategies for wet adhesion despite these impediments. Inspection of mussel foot proteins (Mfps) provides insights into adhesive adaptations. Catecholic Dopa (3,4-dihydroxyphenylalanine) and lysine residues are present in high mole percent in the interfacial Mfps. The siderophore cyclic trichrysobactin also contains high mole percent of catechol and lysine and serves as a simplified mimic of Mfps.This work is focused on use of Mfp-mimetic siderophores and synthetic siderophore analogs as model systems for dissecting the chemical and physical interactions that enable wet adhesion. Variation in number and identity of functional groups appended to the synthetic siderophore analogs allows identification of the specific contributions of those functional groups to wet adhesion. Both catechol and amine functional groups are critical to strong wet adhesion. The primary amine of lysine and catechol cooperatively displace interfacial hydration and bind to the underlying substrate. Variation in the amine identity as well as the amine to catechol ratio within siderophore analogs also has a significant impact on wet adhesive performance.Catechol undergoes a pH-dependent autoxidation in which higher pH leads to faster oxidation by dioxygen. This oxidation abolishes all adhesion of Mfps to mica by pH 7.5, yet many applications of synthetic wet adhesives require adhesion at physiological or oceanic pH. A better understanding of catechol redox chemistry is critical to the design of wet adhesives. To this end, the pH-dependent autoxidation of catechol and substituted catechols was investigated and results are consistent with a mechanism in which O2 oxidizes both the mono-deprotonated and di-deprotonated catechol. A linear Hammett correlation for the pH-independent second order rate constants for catechol autoxidation indicates that catechols become resistant to autoxidation when functionalized with electron withdrawing groups and more susceptible to autoxidation when functionalized with electron donating groups. Analysis of substituent effects through Hammett correlation allows for selection of functionalized catechols with redox properties ideally suited for a given application.

Subjects/Keywords: Chemistry; Materials Science; Adhesion; Catechol; Dopa; Mussel Foot Protein; Siderophore

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APA (6^th Edition):

Maier, G. (2017). Catechol-Cation Synergy in Wet Adhesive Materials. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/42v3x74x

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Maier, Greg. “Catechol-Cation Synergy in Wet Adhesive Materials.” 2017. Thesis, University of California – eScholarship, University of California. Accessed January 22, 2021. http://www.escholarship.org/uc/item/42v3x74x.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Maier, Greg. “Catechol-Cation Synergy in Wet Adhesive Materials.” 2017. Web. 22 Jan 2021.

Vancouver:

Maier G. Catechol-Cation Synergy in Wet Adhesive Materials. [Internet] [Thesis]. University of California – eScholarship, University of California; 2017. [cited 2021 Jan 22]. Available from: http://www.escholarship.org/uc/item/42v3x74x.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Maier G. Catechol-Cation Synergy in Wet Adhesive Materials. [Thesis]. University of California – eScholarship, University of California; 2017. Available from: http://www.escholarship.org/uc/item/42v3x74x

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Oxford

16. Farrell, Sarah Marie. The magnetoencephalographic signature of catechol-O-methyltransferase.

Degree: PhD, 2013, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:bb375074-7912-4f8b-b123-975dff7d88e0 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581202

► Catechol-O-methyltransferase (COMT) metabolizes catechols, notably dopamine. The COMT Val158Met polymorphism influences its enzyme activity, and multiple neural correlates of this genotype on dopaminergic phenotypes have… (more)

▼ Catechol-O-methyltransferase (COMT) metabolizes catechols, notably dopamine. The COMT Val158Met polymorphism influences its enzyme activity, and multiple neural correlates of this genotype on dopaminergic phenotypes have been reported, particularly with regards to working memory. COMT activity can also be regulated pharmacologically by COMT inhibitors. The ‘inverted-U’ relationship between dopamine signalling and cognitive performance predicts that the effects of COMT inhibition will differ according to COMT genotype. The goal of this thesis was to better understand COMT’s impact on brain function and behaviour. Here, 33 subjects homozygous for COMT Val158 (‘Val homozygotes’) and 34 homozygous for COMT Met158 (‘Met homozygotes’) were randomly assigned, double-blind, to a single dose of the brain-penetrant COMT inhibitor tolcapone (200mg) or placebo. They completed the N-back task of working memory, an emotional face processing task, and a gambling task, in a magnetoencephalography (MEG) scanner, allowing both behavioural performance and neural activity to be investigated. The data presented in this thesis confirm that COMT activity influences performance on, and neural activity during, the N-back task, in a way consistent with the inverted-U model of dopamine function. The effect on risky decision making is novel, and indicates that COMT plays roles in domains beyond working memory, and that such domains may also follow an inverted-U. Neural activity during the faces task and the gambling task also show COMT-modulated differences. The behavioural results show that the direction of effect of a drug can be influenced by sequence variation in its target gene. They are of translational relevance, since COMT inhibitors are used in the adjunctive treatment of Parkinson’s disease and are under evaluation in schizophrenia and other disorders. The MEG data show that for the three tasks, there are effects of Val158Met genotype, of tolcapone, and their interaction, on neural activity (for example, the P300 during N-back), revealing a complex temporal and spatial pattern which sheds some light on the neural processing underlying these tasks and their previously reported fMRI correlates.

Subjects/Keywords: 612.8; Cognitive Neuroscience; Neuroscience; Magnetoencephalography; Catechol-o-methyltransferase

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APA (6^th Edition):

Farrell, S. M. (2013). The magnetoencephalographic signature of catechol-O-methyltransferase. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:bb375074-7912-4f8b-b123-975dff7d88e0 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581202

Chicago Manual of Style (16^th Edition):

Farrell, Sarah Marie. “The magnetoencephalographic signature of catechol-O-methyltransferase.” 2013. Doctoral Dissertation, University of Oxford. Accessed January 22, 2021. http://ora.ox.ac.uk/objects/uuid:bb375074-7912-4f8b-b123-975dff7d88e0 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581202.

MLA Handbook (7^th Edition):

Farrell, Sarah Marie. “The magnetoencephalographic signature of catechol-O-methyltransferase.” 2013. Web. 22 Jan 2021.

Vancouver:

Farrell SM. The magnetoencephalographic signature of catechol-O-methyltransferase. [Internet] [Doctoral dissertation]. University of Oxford; 2013. [cited 2021 Jan 22]. Available from: http://ora.ox.ac.uk/objects/uuid:bb375074-7912-4f8b-b123-975dff7d88e0 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581202.

Council of Science Editors:

Farrell SM. The magnetoencephalographic signature of catechol-O-methyltransferase. [Doctoral Dissertation]. University of Oxford; 2013. Available from: http://ora.ox.ac.uk/objects/uuid:bb375074-7912-4f8b-b123-975dff7d88e0 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581202

Portland State University

17. D'Arcy, Karen Ann. Electrochemical methods for speciation of inorganic arsenic.

Degree: PhD, Environmental Science and Management, 1986, Portland State University

URL: https://pdxscholar.library.pdx.edu/open_access_etds/524

► Arsenic is found in the environment in several oxidation states as well as in a variety of organoarsenic compounds. This situation puts additional demands… (more)

▼ Arsenic is found in the environment in several oxidation states as well as in a variety of organoarsenic compounds. This situation puts additional demands on the analysis in that it is desirable to measure the amount of each species, not just all of the arsenic. The reason for this is that the different species have greatly different toxicities; of the major inorganic forms, As(III) is much more toxic than As(V). The goal of this research was to develop a convenient method for the analysis of mixtures of As(III) and As(V) at trace levels. Electroanalytical methods are inherently sensitive to oxidation states of elements and therefore are a natural choice for this problem. In fact, a method was developed some years ago for As(III) that used differential pulse polarography: the detection limit is 0.3 parts per billion (ppb). However, As(V) was not detected since in its usual form as an oxyanion it is electrochemically inactive. There are coordinate compounds formed with catechol, AsL(,n)(n = 1-3), that can be reduced at a mercury electrode, but the active species, AsL, is only a small fraction of the major species, AsL(,3), so the detection limit is only 500 ppb. Many details of the electrochemistry of this unusual compound were examined in this work. In order to improve detection limits, a method involving cathodic stripping was developed. It involves codeposition of copper with arsenic on a mercury electrode to effectively concentrate the analyte. Then the elemental arsenic is converted to arsine, AsH(,3), during a cathodic potential scan. The resulting current peak is proportional to As(III) in the absence of catechol and to the sum of As(III) and As(V) in the presence of catechol. It was observed that the current peak was considerably larger than expected and additional experiments revealed that there was evolution of hydrogen during the formation of arsine. This is rather unusual in electrochemical reactions and so some of the details of this catalyzed coreaction were examined. The result is a fortunate enhancement of detection limit so that As(v) at 40 ppb can be measured.

Subjects/Keywords: Arsenic – Analysis; Conductometric analysis; Catechol

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APA (6^th Edition):

D'Arcy, K. A. (1986). Electrochemical methods for speciation of inorganic arsenic. (Doctoral Dissertation). Portland State University. Retrieved from https://pdxscholar.library.pdx.edu/open_access_etds/524

Chicago Manual of Style (16^th Edition):

D'Arcy, Karen Ann. “Electrochemical methods for speciation of inorganic arsenic.” 1986. Doctoral Dissertation, Portland State University. Accessed January 22, 2021. https://pdxscholar.library.pdx.edu/open_access_etds/524.

MLA Handbook (7^th Edition):

D'Arcy, Karen Ann. “Electrochemical methods for speciation of inorganic arsenic.” 1986. Web. 22 Jan 2021.

Vancouver:

D'Arcy KA. Electrochemical methods for speciation of inorganic arsenic. [Internet] [Doctoral dissertation]. Portland State University; 1986. [cited 2021 Jan 22]. Available from: https://pdxscholar.library.pdx.edu/open_access_etds/524.

Council of Science Editors:

D'Arcy KA. Electrochemical methods for speciation of inorganic arsenic. [Doctoral Dissertation]. Portland State University; 1986. Available from: https://pdxscholar.library.pdx.edu/open_access_etds/524

Portland State University

18. Haak, Ronald P. An investigation of arsenic(V)-catechol complexes.

Degree: MS(M.S.) in Chemistry, Chemistry, 1978, Portland State University

URL: https://pdxscholar.library.pdx.edu/open_access_etds/2849

► There is not, at this time, a simple method for the simultaneous determination of As (III) and As (V) at trace levels. The development… (more)

Subjects/Keywords: Arsenic – Analysis; Catechol; Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Haak, R. P. (1978). An investigation of arsenic(V)-catechol complexes. (Masters Thesis). Portland State University. Retrieved from https://pdxscholar.library.pdx.edu/open_access_etds/2849

Chicago Manual of Style (16^th Edition):

Haak, Ronald P. “An investigation of arsenic(V)-catechol complexes.” 1978. Masters Thesis, Portland State University. Accessed January 22, 2021. https://pdxscholar.library.pdx.edu/open_access_etds/2849.

MLA Handbook (7^th Edition):

Haak, Ronald P. “An investigation of arsenic(V)-catechol complexes.” 1978. Web. 22 Jan 2021.

Vancouver:

Haak RP. An investigation of arsenic(V)-catechol complexes. [Internet] [Masters thesis]. Portland State University; 1978. [cited 2021 Jan 22]. Available from: https://pdxscholar.library.pdx.edu/open_access_etds/2849.

Council of Science Editors:

Haak RP. An investigation of arsenic(V)-catechol complexes. [Masters Thesis]. Portland State University; 1978. Available from: https://pdxscholar.library.pdx.edu/open_access_etds/2849

19. ΚΟΥΡΟΥΝΑΚΗ, ΑΓΓΕΛΙΚΗ. APPLICATION OF DRUG DESIGN METHODS FOR INDUCING NERVE GROWTH FACTOR BIOSYNTHESIS.

Degree: 1995, Institutes outside Greece; Ιδρύματα Εξωτερικού

URL: http://hdl.handle.net/10442/hedi/5220

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THE CLINICAL POTENTIAL OF NERVE GROWTH FACTOR (NGF) AS A THERAPEUTIC AGENT FOR ALZHEIMER'S DISEASE IS UNDERMINED BY ITS INABILITY TO CROSS THE BLOOD BRAIN… (more)

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THE CLINICAL POTENTIAL OF NERVE GROWTH FACTOR (NGF) AS A THERAPEUTIC AGENT FOR ALZHEIMER'S DISEASE IS UNDERMINED BY ITS INABILITY TO CROSS THE BLOOD BRAIN BARRIER. THE ALTERNATIVE OF UP-REGULATING NGF IN THE CENTRAL NERVOUS SYSTEM (CNS) BY NGF-INDUCING COMPOUNDS SEEMS MORE PROMISING, AND DELIVERY OF SUCH AGENTS TO THE BRAIN IS THEREFORE OF GREAT INTEREST. AN INTEGRATED APPROACH, USING DRUG DESIGN METHODS (SITE-SPECIFIC DELIVERY, ISOSTERIC SUBSTITUTION, AND STUDYOF QUANTITATIVE STRUCTURE ACTIVITY RELATIONSHIPS), WAS UNDERTAKEN TO 1) EFFECTIVELY STIMULATE NGF BIOSYNTHESIS IN THE CNS BY PERIPHERAL ADMINISTRATION OF ABRAIN-TARGETED CHEMICAL DELIVERY SYSTEM (CDS) OF A KNOWN INDUCER, 4-METHYLCATECHOL (4MC), 2) PRODUCE NOVEL NGF-INDUCING COMPOUNDS, AND 3) ELUCIDATE THE MECHANISM OF ACTION OF CATECHOL DERIVATIVES AS NGF-INDUCERS. BRAIN-TARGETED CDSS FOR 4MC BASED ON THE DIHYDROPYRIDINE < – > PYRIDINIUM REDOX REACTION WERE DESIGNED AND SYNTHESISED, AS WELL AS A NOVEL BRAIN-TARGETED CATECHOL DERIVATIVE. INVITRO STABILITY STUDIES AND IN VIVO DISTRIBUTION STUDIES IN RATS SUCCESSFULLY DEMONSTRATED THE FEASIBILITY OF SUSTAINED DELIVERY OF 4MC AND DERIVATIVE TO THE RAT BRAIN AFTER PERIPHERAL ADMINISTRATION OF THE CORRESPONDING DIHYDROPYRIDINE CHEMICAL DELIVERY SYSTEMS, AND RAPID PERIPHERAL ELIMINATION TO ASSURE MINIMAL PERIPHERAL SIDE EFFECTS OF THE BIOACTIVE COMPOUNDS. MOREOVER, THE 4MC-CDS EVOKED A 1.8-FOLD INCREASE IN NGF MRNA IN THE HIPPOCAMPAL REGION OF THE RAT BRAIN. BIOISOSTERS OF 4MC WERE SYNTHESISED AND EVALUATED FOR IN VITRO NGF-INDUCING ACTIVITY IN TWO CELL LINES. (ABSTRACT TRUNCATED)

Η ΚΛΙΝΙΚΗ ΔΥΝΑΤΟΤΗΤΑ ΤΟΥ ΠΑΡΑΓΟΝΤΑ ΑΝΑΠΤΥΞΗΣ ΝΕΥΡΩΝΩΝ (NERVE GROWTH FACTOR-NGF)ΩΣ ΘΕΡΑΠΕΥΤΙΚΟΥ ΜΕΣΟΥ ΓΙΑ ΤΗΝ ΝΟΣΟ ΤΟΥ ALZHEIMER ΠΑΡΕΜΠΟΔΙΖΕΤΑΙ ΑΠΟ ΤΗΝ ΑΝΙΚΑΝΟΤΗΤΑ ΤΟΥ ΝΑ ΔΙΑΒΕΙ ΤΟ ΑΙΜΑΤΟΕΓΚΕΦΑΛΙΚΟ ΦΡΑΓΜΟ. Η ΕΝΑΛΛΑΚΤΙΚΗ ΔΥΝΑΤΟΤΗΤΑ ΤΗΣ ΠΡΟΣ ΤΑ ΑΝΩ ΡΥΘΜΙΣΗΣ ΤΟΥ NGF ΣΤΟ ΚΝΣ ΑΠΟ ΕΝΩΣΕΙΣ ΠΟΥ ΕΠΑΓΟΥΝ ΤΗΝ ΠΑΡΑΓΩΓΗ ΤΟΥ, ΔΕΙΧΝΕΙ ΝΑ ΥΠΟΣΧΕΤΑΙ ΠΕΡΙΣΣΟΤΕΡΑ, ΚΑΙ Η ΣΤΟΧΕΥΣΗ ΚΑΙ ΜΕΤΑΦΟΡΑ ΤΕΤΟΙΩΝ ΕΝΩΣΕΩΝ ΣΤΟΝ ΕΓΚΕΦΑΛΟ ΚΑΘΥΣΤΑΤΑΙ ΕΠΟΜΕΝΩΣ ΠΟΛΥ ΕΝΔΙΑΦΕΡΟΥΣΑ. ΜΙΑ ΟΛΟΚΛΗΡΩΜΕΝΗ ΠΡΟΣΕΓΓΙΣΗ, ΧΡΗΣΙΜΟΠΟΙΩΝΤΑΣ ΜΕΘΟΔΟΥΣ ΣΧΕΔΙΑΣΜΟΥ ΦΑΡΜΑΚΩΝ (ΕΚΛΕΚΤΙΚΗ ΣΕ ΣΥΓΚΕΚΡΙΜΕΝΗΠΕΡΙΟΧΗ ΜΕΤΑΦΟΡΑ ΚΑΙ ΑΠΟΔΕΣΜΕΥΣΗ, ΙΣΟΣΤΕΡΗΣ ΥΠΟΚΑΤΑΣΤΑΣΗ, ΚΑΙ ΜΕΛΕΤΗ ΠΟΣΟΤΙΚΗΣ ΣΧΕΣΗΣ ΔΟΜΗΣ ΔΡΑΣΗΣ) ΔΙΕΚΠΕΡΑΙΩΘΗΚΕ ΓΙΑ ΤΗΝ 1) ΑΠΟΤΕΛΕΣΜΑΤΙΚΗ ΕΠΑΓΩΓΗ ΒΙΟΣΥΝΘΕΣΗΣ ΤΟΥ NGF ΣΤΟ ΚΝΣ ΜΕΤΑ ΑΠΟ ΠΕΡΙΦΕΡΙΚΗ ΧΟΡΗΓΗΣΗ ΧΗΜΙΚΟΥ ΣΥΣΤΗΜΑΤΟΣ ΑΠΟΔΕΣΜΕΥΣΗΣ ΣΤΟΝ ΕΓΚΕΦΑΛΟ (CDS) ΓΝΩΣΤΟΥ ΕΠΑΓΩΓΕΑ, ΤΗΣ 4-ΜΕΘΥΛΟΚΑΤΕΧΟΛΗΣ, 2) ΠΑΡΑΓΩΓΗ ΝΕΩΝ ΕΝΩΣΕΩΝ ΕΠΑΓΩΓΕΩΝ ΤΟΥ NGF, 3) ΔΙΕΥΚΡΙΝΙΣΗ ΤΟΥ ΜΗΧΑΝΙΣΜΟΥ ΔΡΑΣΗΣ ΤΩΝ ΚΑΤΕΧΟΛΙΚΩΝ ΠΑΡΑΓΩΓΩΝ ΩΣ NGF-ΕΠΑΓΩΓΕΙΣ. ΧΗΜΙΚΑ ΣΥΣΤΗΜΑΤΑ ΑΠΟΔΕΣΜΕΥΣΗΣ ΣΤΟΝ ΕΓΚΕΦΑΛΟΤΗΣ 4- ΜΕΘΥΛΟΚΑΤΕΧΟΛΗΣ, ΒΑΣΙΣΜΕΝΑ ΣΤΗ ΟΞΕΙΔΟΑΝΑΓΩΓΙΚΗ ΑΝΤΙΔΡΑΣΗ ΔΙΥΔΡΟΠΥΡΙΔΙΝΗ < – > ΠΥΡΙΔΙΝΙΟΥ ΑΛΑΣ, ΣΧΕΔΙΑΣΤΗΚΑΝ ΚΑΙ ΣΥΝΤΕΘΗΚΑΝ, ΟΠΩΣ ΕΠΙΣΗΣ ΚΑΙ ΝΕΟ ΚΑΤΕΥΘΥΝΟΜΕΝΟ ΣΤΟΝ ΕΓΚΕΦΑΛΟ ΚΑΤΕΧΟΛΙΚΟ ΠΑΡΑΓΩΓΟ. (ΠΕΡΙΚΟΠΗ ΠΕΡΙΛΗΨΗΣ)

Subjects/Keywords: CATECHOL; CDS; CNS; NGF

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

ΚΟΥΡΟΥΝΑΚΗ, . �. (1995). APPLICATION OF DRUG DESIGN METHODS FOR INDUCING NERVE GROWTH FACTOR BIOSYNTHESIS. (Thesis). Institutes outside Greece; Ιδρύματα Εξωτερικού. Retrieved from http://hdl.handle.net/10442/hedi/5220

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

ΚΟΥΡΟΥΝΑΚΗ, ΑΓΓΕΛΙΚΗ. “APPLICATION OF DRUG DESIGN METHODS FOR INDUCING NERVE GROWTH FACTOR BIOSYNTHESIS.” 1995. Thesis, Institutes outside Greece; Ιδρύματα Εξωτερικού. Accessed January 22, 2021. http://hdl.handle.net/10442/hedi/5220.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

ΚΟΥΡΟΥΝΑΚΗ, ΑΓΓΕΛΙΚΗ. “APPLICATION OF DRUG DESIGN METHODS FOR INDUCING NERVE GROWTH FACTOR BIOSYNTHESIS.” 1995. Web. 22 Jan 2021.

Vancouver:

ΚΟΥΡΟΥΝΑΚΗ �. APPLICATION OF DRUG DESIGN METHODS FOR INDUCING NERVE GROWTH FACTOR BIOSYNTHESIS. [Internet] [Thesis]. Institutes outside Greece; Ιδρύματα Εξωτερικού; 1995. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10442/hedi/5220.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

ΚΟΥΡΟΥΝΑΚΗ �. APPLICATION OF DRUG DESIGN METHODS FOR INDUCING NERVE GROWTH FACTOR BIOSYNTHESIS. [Thesis]. Institutes outside Greece; Ιδρύματα Εξωτερικού; 1995. Available from: http://hdl.handle.net/10442/hedi/5220

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Michigan Technological University

20. Narkar, Ameya R. REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY.

Degree: PhD, Department of Biomedical Engineering, 2018, Michigan Technological University

URL: https://digitalcommons.mtu.edu/etdr/741

► Catecholic groups in mussel adhesive proteins transition from being strongly adhesive in a reduced state under acidic conditions to being weakly adhesive in an… (more)

▼ Catecholic groups in mussel adhesive proteins transition from being strongly adhesive in a reduced state under acidic conditions to being weakly adhesive in an oxidized state under basic conditions. Here, we exploit this pH responsive behavior of catechol and demonstrate that its oxidation state can be manipulated by incorporation of boronic acid to facilitate reversible transitions between strong and weak adhesion. Our first approach involved the addition of 3- acrylamido phenylboronic acid (APBA) to dopamine methacrylamide (DMA) containing adhesives. The synthesized adhesives showed strong adhesion to quartz surface in an acidic medium (pH 3), while weak adhesion was observed on raising the pH to a basic value (pH 9), due to unavailability of catechol and boronic acid because of the formation of a reversible catechol-boronate complex. Boronic acid not only contributed to adhesion at an acidic pH, but also allowed the catechol to reversibly interact with the surface in response to changing pH. In our second study, we demonstrated that addition of an anionic monomer, acrylic acid (AAc), preserved the reduced and adhesive state of catechol even at a neutral to mildly basic pH, while the addition of a cationic monomer, N-(aminopropyl) methacrylamide hydrochloride, led to the oxidized and weak adhesive state at higher basic pH values. This was due to the buffering of local pH offered by the incorporation of the ionic species, which affected the oxidation state of catechol. Although the ideal pH for formation of the complex is 9, it readily forms at neutral to mildly basic pH, leading to decreased adhesion and limiting the adhesive’s application in physiological and marine pH environments. In our third 2 approach, adding elevated amounts of AAc to smart adhesives consisting of DMA and APBA led to strong adhesion to quartz substrate at neutral to mildly basic pH. Moreover, the complex formed at pH 9 remained reversible and the interfacial binding could be tuned by changing the pH during successive contact cycles. pH 3 was required to break the complex and recover the strong adhesive property. Bulk adhesives analyzed in our first three approaches needed extended periods of incubation (up to 30 min) to switch between their adhesive and non-adhesive states. This is because infiltration of the pH media into the bulk polymer is limited by the slow process of diffusion. Finally, we fabricated a hybrid adhesive which was composed of gecko-inspired microstructured PDMS pillars (aspect ratios of 0.4-2) coated with the smart adhesive that we developed in our first approach. By tuning the aspect ratio of the bare templates, hybrid structures that showed strong, elevated adhesion at pH 3, were obtained. The increased adhesion was attributed to contact-splitting effects due to the micropatterning combined with the interfacial binding of the smart adhesive. On the other hand, formation of the complex, and the associated swelling of the adhesive together contributed to a significant decrease in adhesion at pH 9. Additionally, the… Advisors/Committee Members: Bruce P. Lee.

Subjects/Keywords: Mussel Adhesion; Catechol; Reversible adhesion; Smart Adhesive; Rapid adhesion; Biomaterials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Narkar, A. R. (2018). REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/741

Chicago Manual of Style (16^th Edition):

Narkar, Ameya R. “REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY.” 2018. Doctoral Dissertation, Michigan Technological University. Accessed January 22, 2021. https://digitalcommons.mtu.edu/etdr/741.

MLA Handbook (7^th Edition):

Narkar, Ameya R. “REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY.” 2018. Web. 22 Jan 2021.

Vancouver:

Narkar AR. REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY. [Internet] [Doctoral dissertation]. Michigan Technological University; 2018. [cited 2021 Jan 22]. Available from: https://digitalcommons.mtu.edu/etdr/741.

Council of Science Editors:

Narkar AR. REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY. [Doctoral Dissertation]. Michigan Technological University; 2018. Available from: https://digitalcommons.mtu.edu/etdr/741

Michigan Technological University

21. Narkar, Ameya Ravindra. PH RESPONSIVE, ADHESIVE HYDROGELS BASED ON REVERSIBLE CATECHOL - BORONIC ACID COMPLEXATION.

Degree: PhD, Department of Biomedical Engineering, 2015, Michigan Technological University

URL: https://digitalcommons.mtu.edu/etds/1002

► Smart hydrogel adhesives with tunable properties consist of adhesive moieties in the polymer network that respond to external stimuli like pH, temperature, etc. Responsiveness… (more)

▼ Smart hydrogel adhesives with tunable properties consist of adhesive moieties in the polymer network that respond to external stimuli like pH, temperature, etc. Responsiveness of smart adhesives to pH, in particular, is important because of the simple actuation mechanism and the ability to achieve facile bonding and debonding upon command. Covalently crosslinked hydrogel adhesives were prepared by employing an N-HEAA (hydroxyethyl acrylamide) backbone embedded with dopamine methacrylamide (DMA), a marine mussel inspired adhesive protein and 3-acrylamido phenylboronic acid (AAPBA), to determine the effect of pH on the interfacial binding properties of the hydrogel adhesive with a borosilicate glass substrate. Swelling tests were performed to determine the response of the synthesized hydrogels to changes in pH values. These tests revealed that in a pH 3 buffered solution, hydrogels containing DMA and AAPBA showed a shrinking trend, while at pH 9, a swelling phenomenon was observed. The evidence from oscillatory rheometry tests exhibited elevated loss moduli (Gʹ) for hydrogels with DMA and AAPBA at pH 9, when compared to the relevant controls. In conjunction, the data from swelling tests and rheometry explained the unusual swelling of the hydrogels and formation of the catechol-boronate complex at pH 9, which caused more than an order of magnitude of increase in the Gʺ owing to the viscous dissipation of energy at that pH as compared to the control gels. The interfacial binding properties were tested by performing contact mechanics tests, in the presence of an acidic/basic medium. The maximum work of adhesion values of 0.59mJ/m² were obtained for hydrogels with 2.5mol% DMA and 10mol%AAPBA in the polymer network, when tested against a borosilicate glass surface wetted with 250μL of the pH 3 solution. At pH 9, this value reduced to as much as 1/5th of its value at pH 3. Earlier works have proposed that the oxidation of the catecholic groups that are chiefly responsible for adhesion with an inorganic substrate, is a deterrent to the adhesive properties of a hydrogel. We have accomplished the development of a model adhesive system in which we utilized the pH responsiveness of the hydrogels to demonstrate the elevated and reduced works of adhesion at acidic and basic pHs respectively. We believe that the catechol- boronic acid complex at pH 9 will allow for the reversible DOPA- facilitated adhesion. Reversibility studies performed in this direction revealed that while the hydrogels could recover their shape in terms of the measured diameters, further testing and analysis is required for understanding the ideal composition of the hydrogel and environmental trigger to actuate reversibility. Advisors/Committee Members: Bruce P. Lee.

Subjects/Keywords: adhesive; catechol; compelxation; pH; reversible; Biomedical Engineering and Bioengineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Narkar, A. R. (2015). PH RESPONSIVE, ADHESIVE HYDROGELS BASED ON REVERSIBLE CATECHOL - BORONIC ACID COMPLEXATION. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etds/1002

Chicago Manual of Style (16^th Edition):

Narkar, Ameya Ravindra. “PH RESPONSIVE, ADHESIVE HYDROGELS BASED ON REVERSIBLE CATECHOL - BORONIC ACID COMPLEXATION.” 2015. Doctoral Dissertation, Michigan Technological University. Accessed January 22, 2021. https://digitalcommons.mtu.edu/etds/1002.

MLA Handbook (7^th Edition):

Narkar, Ameya Ravindra. “PH RESPONSIVE, ADHESIVE HYDROGELS BASED ON REVERSIBLE CATECHOL - BORONIC ACID COMPLEXATION.” 2015. Web. 22 Jan 2021.

Vancouver:

Narkar AR. PH RESPONSIVE, ADHESIVE HYDROGELS BASED ON REVERSIBLE CATECHOL - BORONIC ACID COMPLEXATION. [Internet] [Doctoral dissertation]. Michigan Technological University; 2015. [cited 2021 Jan 22]. Available from: https://digitalcommons.mtu.edu/etds/1002.

Council of Science Editors:

Narkar AR. PH RESPONSIVE, ADHESIVE HYDROGELS BASED ON REVERSIBLE CATECHOL - BORONIC ACID COMPLEXATION. [Doctoral Dissertation]. Michigan Technological University; 2015. Available from: https://digitalcommons.mtu.edu/etds/1002

University of Minnesota

22. Dostal, Allison. Chronic and Acute Effects of Green Tea Extract and Catechol-O-methyltransferase Genotype on Body Composition and Obesity-Associated Hormones in Overweight and Obese Postmenopausal Women.

Degree: PhD, Nutrition, 2015, University of Minnesota

URL: http://hdl.handle.net/11299/190443

► This dissertation details the chronic and acute effects of green tea extract (GTE) supplementation (1315 mg green tea catechins/day, 843 mg as (-)-epigallocatechin-3-gallate, [EGCG]) on… (more)

▼ This dissertation details the chronic and acute effects of green tea extract (GTE) supplementation (1315 mg green tea catechins/day, 843 mg as (-)-epigallocatechin-3-gallate, [EGCG]) on body composition, obesity-associated hormones, glucose homeostasis, and satiety in overweight and obese postmenopausal women at increased risk for breast cancer due to high mammographic density. Participants in the forthcoming studies were a subset of participants drawn from the Minnesota Green Tea Trial (MGTT), which was a randomized, placebo-controlled, double-blind, phase II clinical trial designed to determine the effects of supplementing GTE for one year on breast cancer risk factors including mammographic density, reproductive hormones, insulin-like growth factor (IGF) axis proteins, and F2-isoprostanes, a recognized biomarker of oxidative stress. Effect modification by catechol-O-methyltransferase (COMT), an enzyme involved in the metabolism of green tea catechins, estrogens, and norepinephrine, was also analyzed for all endpoints, due to its potential role in modulating the impact of GTE on breast cancer risk factors. Chapter 1 provides a brief introduction to the MGTT and the forthcoming chapters. Chapter 2 presents a review of the literature, providing context for the MGTT and ancillary studies. Chapter 3 describes the effect of GTE on anthropometric variables, obesity-associated hormones (leptin, ghrelin, adiponectin, and insulin) and markers of glucose homeostasis (blood glucose concentrations and the homeostasis measure of insulin resistance [HOMA-IR]) in 237 participants. In this study, no changes in energy intake or anthropometric measurements were observed in women taking GTE or placebo. Similarly, no changes were seen in circulating leptin, ghrelin, adiponectin, or glucose concentrations. However, among participants with baseline insulin ≥10 µIU/mL, there was a reduction in insulin concentration in the GTE group over 12 months compared to the placebo group and participants with baseline insulin < 10 µIU/mL in either group (P < 0.01). Participants with the homozygous high-activity (G/G) form of COMT showed significantly lower adiponectin and higher insulin concentrations at month 12 as compared to those with the low-activity (A/A) genotype, regardless of treatment group. Chapter 4 describes the more specific effects of GTE on body composition as measured by dual-energy x-ray absorptiometry (DXA), including total body fat, % body fat, region-specific adiposity, and bone mineral density (BMD) in 121 participants. These results were correlated with measures of leptin, adiponectin, and insulin. No changes in BMI, total fat mass, % body fat, or BMD were observed in women taking GTE compared to placebo; however, a reduction in visceral adipose tissue mass in GTE participants as compared to the placebo group nearly reached significance. Interactions were observed between treatment, time, and baseline BMI for gynoid % fat and tissue % fat, with more favorable results seen in the GTE group. No changes were seen in circulating…

Subjects/Keywords: adiponectin; catechol-O-methyltransferase; green tea; insulin; obesity; postmenopausal women

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dostal, A. (2015). Chronic and Acute Effects of Green Tea Extract and Catechol-O-methyltransferase Genotype on Body Composition and Obesity-Associated Hormones in Overweight and Obese Postmenopausal Women. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/190443

Chicago Manual of Style (16^th Edition):

Dostal, Allison. “Chronic and Acute Effects of Green Tea Extract and Catechol-O-methyltransferase Genotype on Body Composition and Obesity-Associated Hormones in Overweight and Obese Postmenopausal Women.” 2015. Doctoral Dissertation, University of Minnesota. Accessed January 22, 2021. http://hdl.handle.net/11299/190443.

MLA Handbook (7^th Edition):

Dostal, Allison. “Chronic and Acute Effects of Green Tea Extract and Catechol-O-methyltransferase Genotype on Body Composition and Obesity-Associated Hormones in Overweight and Obese Postmenopausal Women.” 2015. Web. 22 Jan 2021.

Vancouver:

Dostal A. Chronic and Acute Effects of Green Tea Extract and Catechol-O-methyltransferase Genotype on Body Composition and Obesity-Associated Hormones in Overweight and Obese Postmenopausal Women. [Internet] [Doctoral dissertation]. University of Minnesota; 2015. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/11299/190443.

Council of Science Editors:

Dostal A. Chronic and Acute Effects of Green Tea Extract and Catechol-O-methyltransferase Genotype on Body Composition and Obesity-Associated Hormones in Overweight and Obese Postmenopausal Women. [Doctoral Dissertation]. University of Minnesota; 2015. Available from: http://hdl.handle.net/11299/190443

University of Minnesota

23. Fielding, Andrew Jay. Kinetic and spectroscopic studies of cobalt- and manganese-substituted extradiol-cleaving homoprotocatechuate 2,3-dioxygenases.

Degree: PhD, Chemistry, 2013, University of Minnesota

URL: http://hdl.handle.net/11299/171095

► Homoprotocatechuate (HPCA) 2,3-dioxygenase (HPCD) is an Fe(II)-dependent extradiol-cleaving dioxygenase, which oxidatively cleaves the aromatic C(2)-C(3) bond of its catecholic substrate. Here we compare the reactivity… (more)

▼ Homoprotocatechuate (HPCA) 2,3-dioxygenase (HPCD) is an Fe(II)-dependent extradiol-cleaving dioxygenase, which oxidatively cleaves the aromatic C(2)-C(3) bond of its catecholic substrate. Here we compare the reactivity of Fe-HPCD with its Mn(II)- and Co(II)-substituted analogues. While Mn-HPCD exhibits steady-state kinetic parameters comparable to those of Fe-HPCD, Co-HPCD exhibits significantly higher K_M^O2 and k_cat values. The high activity of Co-HPCD is surprising, given that cobalt has the highest standard M(III/II) redox potential of the three metals. These kinetic differences and the spectroscopic properties of Co-HPCD have proven to be useful in further exploring the unique O₂ activation mechanism associated with the extradiol dioxygenase family.</DISS_para> <DISS_para>Employing the electron-poor substrate analogue 4-nitrocatechol (4NC), which is expected to slow down the rate of catechol oxidation, we were able to trap and characterize the initial O₂-adduct in the single-turnover reaction of 4-nitrocatechol by Co-HPCD. This intermediate exhibits an S = 1/2 EPR signal typical of low-spin Co(III)−superoxide complexes. Both the formation and decay of the low-spin Co(III)−superoxide intermediate are slow compared to the analogous steps for turnover of 4NC by native high-spin Fe(II)-HPCD, which is likely to remain high-spin upon O₂ binding. Possible effects of the observed spin-state transition upon the rate of O₂ binding and catechol oxidation are discussed.</DISS_para> <DISS_para>Two transient intermediates were detected in the reaction of the [M-HPCD(4XC)] enzyme-substrate complexes (M = Mn or Co, and 4XC = 4-halocatechols, where X = F, Cl, and Br) with O₂. The first intermediate (Co4XlCInt1) exhibited an S = 1/2 EPR signal associated with an organic radical species. Based on the UV-Vis and EPR data, Co^4XCInt1 was assigned to a unique low-spin [Co(III)(4XSQ^*)(hydro)peroxo] species where the semiquinone radical is localized onto C4 of the ring. M^4XCInt2 was observed to have a high-spin metal(II) center by EPR and exhibit intense chromophores similar to the independently synthesized halogenated quinones (4XQ). Based on the UV-Vis and EPR data, M^4XCInt2 is assigned to a [M(II)(4XQ)(hydro)peroxo] species. The M^4XCInt2 species were further characterized by resonance Raman spectroscopy. Resonance enhanced vibrations between 1350-1450 cm^-1 suggest that M4XCInt2 is a metal-semiquinone species, conflicting with the initial assignment of these intermediates as a quinone species. Based on the EPR and resonance Raman data, M^4XCInt2 might be assigned to a [M(II)(SQ^*)O₂^*-] diradical species.

Subjects/Keywords: Catechol; Cobalt -substituted; Dioxygenase; EPR; Kinetics; Manganese-substituted; Chemistry

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APA (6^th Edition):

Fielding, A. J. (2013). Kinetic and spectroscopic studies of cobalt- and manganese-substituted extradiol-cleaving homoprotocatechuate 2,3-dioxygenases. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/171095

Chicago Manual of Style (16^th Edition):

Fielding, Andrew Jay. “Kinetic and spectroscopic studies of cobalt- and manganese-substituted extradiol-cleaving homoprotocatechuate 2,3-dioxygenases.” 2013. Doctoral Dissertation, University of Minnesota. Accessed January 22, 2021. http://hdl.handle.net/11299/171095.

MLA Handbook (7^th Edition):

Fielding, Andrew Jay. “Kinetic and spectroscopic studies of cobalt- and manganese-substituted extradiol-cleaving homoprotocatechuate 2,3-dioxygenases.” 2013. Web. 22 Jan 2021.

Vancouver:

Fielding AJ. Kinetic and spectroscopic studies of cobalt- and manganese-substituted extradiol-cleaving homoprotocatechuate 2,3-dioxygenases. [Internet] [Doctoral dissertation]. University of Minnesota; 2013. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/11299/171095.

Council of Science Editors:

Fielding AJ. Kinetic and spectroscopic studies of cobalt- and manganese-substituted extradiol-cleaving homoprotocatechuate 2,3-dioxygenases. [Doctoral Dissertation]. University of Minnesota; 2013. Available from: http://hdl.handle.net/11299/171095

University of Melbourne

24. Parkin, Georgia May. Catechol metabolism and glutamate uptake in the prefrontal cortex of subjects with schizophrenia: implications for cognitive function.

Degree: 2019, University of Melbourne

URL: http://hdl.handle.net/11343/224293

► My thesis comprises of two projects, the first which investigates catechol-O-methyltransferase (COMT) protein levels by genotype (chapter 1 and 2), and the second which investigates… (more)

▼ My thesis comprises of two projects, the first which investigates catechol-O-methyltransferase (COMT) protein levels by genotype (chapter 1 and 2), and the second which investigates excitatory amino acid transporter (EAAT)1 and EAAT2 and metabotropic glutamate receptor 5 mRNA levels (chapter 3) in the prefrontal cortex of subjects with schizophrenia. Project 1. COMT genotype has previously been associated with cognitive function; I hypothesized that COMT genotype would also be associated with differing levels of cortical COMT protein. Using western blotting, I measured protein levels of the two COMT protein isoforms, membrane bound (MB-) COMT and soluble (S-) COMT, as well as beta-actin protein levels, in Brodmann’s area (BA) 9 of 199 individuals, 119 of whom had psychiatric disorders. I have shown that levels of S-COMT protein vary with genotype at rs4818 and rs4680, but not rs737865 and rs165599 (rs4818 genotype: CC<CG, p=0.03, CC<GG, p=0.002; rs4680 genotype: AA<GG, p=0.001), and that levels of MB-COMT protein vary with genotype at rs165599 (GG<AG, p=0.02, GG<AA, p=0.04). As S-COMT is located in the cytosol where it is unlikely to have access to dopamine, my results contest the belief that the associations between rs4680, rs4818 and cognition are through COMT-mediated dopamine degradation. Instead, I propose that S-COMT protein modulates cognition through metabolism of other catechol structures, such as catecholestrogens. In support of this, an Affymetrix™ microarray analysis has found that the cortical expression of 15 genes vary by COMT genotype at rs4680 and/or rs4818, with 11 of these genes previously shown to be regulated by estrogen. COMT protein levels were not affected by a diagnosis of schizophrenia (p>0.05), suggesting that this variation in protein level by genotype occurs even in the presence of cortical dysfunction. Project 2. EAAT1 and EAAT2 mediate glutamatergic neurotransmission and prevent glutamate excitotoxicity, through the perisynaptic binding and transportation of glutamate into glia. An Affymetrix™ microarray analysis which preceded my PhD studies found a 36% increase in EAAT1 mRNA levels in BA9 of subjects with schizophrenia. The aim of this chapter was to determine whether changes in EAAT1 and EAAT2 mRNA levels occur in other cortical regions from subjects with schizophrenia. I used quantitative PCR to compare mRNA levels of EAAT1, EAAT2 and mGluR5 across post-mortem BA10, BA44 and BA46 of subjects with schizophrenia (n=20) and non-psychiatric controls (n=18). Reactions were measured in triplicate with results normalised to the geometric mean of two stably expressed reference genes – transcription factor B1, mitochondrial (TFB1M) and S-phase kinase-associated protein 1A (SKP1A). EAAT1 mRNA levels were significantly higher in BA10 (U=67, p=0.0006) and BA44 (U=68, p=0.0007), and EAAT2 mRNA levels w¬ere significantly higher in BA10 (U=85, p=0.0047), with mRNA levels of both transporters showing no change in BA46 (EAAT1: U=164, p=0.65; EAAT2: U=146, p=0.33), of subjects with…

Subjects/Keywords: post-mortem; glutamate; catechol-O-methyltransferase; schizophrenia; western blot; qPCR

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APA (6^th Edition):

Parkin, G. M. (2019). Catechol metabolism and glutamate uptake in the prefrontal cortex of subjects with schizophrenia: implications for cognitive function. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/224293

Chicago Manual of Style (16^th Edition):

Parkin, Georgia May. “Catechol metabolism and glutamate uptake in the prefrontal cortex of subjects with schizophrenia: implications for cognitive function.” 2019. Doctoral Dissertation, University of Melbourne. Accessed January 22, 2021. http://hdl.handle.net/11343/224293.

MLA Handbook (7^th Edition):

Parkin, Georgia May. “Catechol metabolism and glutamate uptake in the prefrontal cortex of subjects with schizophrenia: implications for cognitive function.” 2019. Web. 22 Jan 2021.

Vancouver:

Parkin GM. Catechol metabolism and glutamate uptake in the prefrontal cortex of subjects with schizophrenia: implications for cognitive function. [Internet] [Doctoral dissertation]. University of Melbourne; 2019. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/11343/224293.

Council of Science Editors:

Parkin GM. Catechol metabolism and glutamate uptake in the prefrontal cortex of subjects with schizophrenia: implications for cognitive function. [Doctoral Dissertation]. University of Melbourne; 2019. Available from: http://hdl.handle.net/11343/224293

Louisiana State University

25. Poddar, Nimesh Bharat. An Experimental Investigation of the Role of Small Hydrocarbons and Combustion-Generated Nanoparticles on the Formation and Growth Reactions of Polycyclic Aromatic Hydrocarbons during the Pyrolysis of a Model-Fuel and Hydrocarbon Gases.

Degree: PhD, Chemical Engineering, 2012, Louisiana State University

URL: etd-11052012-101847 ; https://digitalcommons.lsu.edu/gradschool_dissertations/403

► Polycyclic aromatic hydrocarbons (PAH) are an important class of environmental pollutants formed during fuel combustion or pyrolysis. Therefore, an experimental study has… (more)

▼ Polycyclic aromatic hydrocarbons (PAH) are an important class of environmental pollutants formed during fuel combustion or pyrolysis. Therefore, an experimental study has been undertaken to better understand the formation and growth pathways of PAH. To investigate the efficacy of C₃ species as PAH growth agents in the context of solid fuels, pyrolysis experiments have been performed in an isothermal quartz flow reactor in the temperature range of 700–1000 °C and a fixed residence time of 0.3 s. Experiments are performed with the C₃ hydrocarbon, propyne; with catechol (ortho-dihydroxybenzene), a model-fuel representative of aromatic moieties in coal and biomass fuels; and with propyne and catechol together. Further, to better understand the role of fuel components and their decomposition products in PAH growth reactions, pyrolysis and co-pyrolysis experiments are performed using 1,3-butadiene (C₄ hydrocarbon) and propyne as fuels at the above described experimental conditions. The results of the catechol/propyne as well as the 1,3-butadiene/propyne co-pyrolysis experiments reveal important synergistic effects that lead to enhanced production of PAH ≥ 3 rings. Product yields will be presented, as functions of temperature, and the reactions responsible for the enhanced yields of PAH will be discussed. The third set of experiments are performed to investigate the effects of inorganics on PAH and their precursor species. A product mixture generated from gas-phase pyrolysis of catechol at 825 °C and a residence time of 5 s is passed through a bed of NiO (the prevalent form of nickel in combustion-generated ash particles) before exiting the reactor. NiO causes the following dramatic effects – PAH yields are reduced by 86% as compared to the case when no inorganics are present, complete depletion of all the acetylenic species is observed, and no solid carbon is observed. The same experiment performed at 1000 °C exhibits similar effects of NiO. High-pressure liquid chromatography with diode-array ultraviolet-visible absorbance detection and mass spectrometric detection (HPLC/UV/MS), an isomer-specific technique for PAH analysis has been employed. HPLC analysis of the pyrolysis products of catechol, brown coal, propyne, catechol/propyne, and 1,3-butadiene/propyne reported in this study is one of the most extensive of its kind for these fuels.

Subjects/Keywords: PAH; Catechol; HPLC/UV/MS; Pyrolysis; Nickel oxide; Propyne; Butadiene

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APA (6^th Edition):

Poddar, N. B. (2012). An Experimental Investigation of the Role of Small Hydrocarbons and Combustion-Generated Nanoparticles on the Formation and Growth Reactions of Polycyclic Aromatic Hydrocarbons during the Pyrolysis of a Model-Fuel and Hydrocarbon Gases. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-11052012-101847 ; https://digitalcommons.lsu.edu/gradschool_dissertations/403

Chicago Manual of Style (16^th Edition):

Poddar, Nimesh Bharat. “An Experimental Investigation of the Role of Small Hydrocarbons and Combustion-Generated Nanoparticles on the Formation and Growth Reactions of Polycyclic Aromatic Hydrocarbons during the Pyrolysis of a Model-Fuel and Hydrocarbon Gases.” 2012. Doctoral Dissertation, Louisiana State University. Accessed January 22, 2021. etd-11052012-101847 ; https://digitalcommons.lsu.edu/gradschool_dissertations/403.

MLA Handbook (7^th Edition):

Poddar, Nimesh Bharat. “An Experimental Investigation of the Role of Small Hydrocarbons and Combustion-Generated Nanoparticles on the Formation and Growth Reactions of Polycyclic Aromatic Hydrocarbons during the Pyrolysis of a Model-Fuel and Hydrocarbon Gases.” 2012. Web. 22 Jan 2021.

Vancouver:

Poddar NB. An Experimental Investigation of the Role of Small Hydrocarbons and Combustion-Generated Nanoparticles on the Formation and Growth Reactions of Polycyclic Aromatic Hydrocarbons during the Pyrolysis of a Model-Fuel and Hydrocarbon Gases. [Internet] [Doctoral dissertation]. Louisiana State University; 2012. [cited 2021 Jan 22]. Available from: etd-11052012-101847 ; https://digitalcommons.lsu.edu/gradschool_dissertations/403.

Council of Science Editors:

Poddar NB. An Experimental Investigation of the Role of Small Hydrocarbons and Combustion-Generated Nanoparticles on the Formation and Growth Reactions of Polycyclic Aromatic Hydrocarbons during the Pyrolysis of a Model-Fuel and Hydrocarbon Gases. [Doctoral Dissertation]. Louisiana State University; 2012. Available from: etd-11052012-101847 ; https://digitalcommons.lsu.edu/gradschool_dissertations/403

University of Georgia

26. White, Evan Michael. Stimuli-responsive polymer architectures.

Degree: 2015, University of Georgia

URL: http://hdl.handle.net/10724/31531

► Light-responsive polymers systems, in both the dry state and hydrogel state were prepared to investigate nano-scale light-induced transitions. Pendant spiropyran (meth)acrylated block copolymers were fabricated… (more)

Subjects/Keywords: stimuli-responsive; block copolymer; spiropyran; hydrogel; biomimetic; catechol

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

White, E. M. (2015). Stimuli-responsive polymer architectures. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/31531

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

White, Evan Michael. “Stimuli-responsive polymer architectures.” 2015. Thesis, University of Georgia. Accessed January 22, 2021. http://hdl.handle.net/10724/31531.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

White, Evan Michael. “Stimuli-responsive polymer architectures.” 2015. Web. 22 Jan 2021.

Vancouver:

White EM. Stimuli-responsive polymer architectures. [Internet] [Thesis]. University of Georgia; 2015. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10724/31531.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

White EM. Stimuli-responsive polymer architectures. [Thesis]. University of Georgia; 2015. Available from: http://hdl.handle.net/10724/31531

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Manchester

27. Czarnota, Sylwia. A study of enzymatic methyl transfer catalysed by COMT : mechanism and structural biology.

Degree: PhD, 2019, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-enzymatic-methyl-transfer-catalysed-by-comt-mechanism-and-structural-biology(a5c9f031-6bb8-4805-a409-83b849ba32ad).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.804098

► Looking at protein structure and studying changes in active site geometry is a fundamental step to understand how enzymes work, how the reaction proceeds and… (more)

▼ Looking at protein structure and studying changes in active site geometry is a fundamental step to understand how enzymes work, how the reaction proceeds and it gives absolutely essential background for potential drug design and development. Enzymes that transfer methyl groups (methyltransferases, MTs) are exciting targets for therapeutic intervention in a range of disorders. COMT (catechol-O-methyltransferase) is a model system for the study of enzyme-catalysed methyl transfer, but is also a very important drug target, as inhibition of this enzyme is a strategy for the treatment of a range of neurological disorders including Parkinson's disease, depression and schizophrenia. This thesis primarily concerns the use of nuclear magnetic resonance (NMR) spectroscopy to study the reactant and transition state analogue (TSA) of human S-COMT. To achieve that, firstly, two NMR backbone assignments of COMT ternary complexes were determined. One with sinefungin, a fungal-derived inhibitor that possesses transition state-like charge on the transferring methyl group; and the second with S-Adenosyl-L-methionine (SAM), which is the major methyl donor for MTs, naturally present in organisms. Two X-ray crystal structures of the same complexes were obtained in high resolution. Comparisons between these complexes were done with the aid of computational studies, identifying subtle conformational differences in the active sites of the two ternary complexes. Results were consistent between all three methods, leading to the conclusion of active site 'compaction' and electrostatic stabilization between the transferring methyl group and 'equatorial' residues that are orthogonal to the donor-acceptor coordinate. High pressure NMR (up to 2500 bar) was next used to probe protein flexibility and rigidity, as well as NMR relaxation measurements, to study dynamics of the backbone. Both indicated high stability of the protein and showed that the majority of the protein is highly ordered. Those methods also indicated C-terminus stabilisation, most likely due to the dimer interface occurring there, which could be the focus of future work.

Subjects/Keywords: enzyme; Catechol-O-methyltransferase; COMT; nuclear magnetic resonance (NMR)

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APA (6^th Edition):

Czarnota, S. (2019). A study of enzymatic methyl transfer catalysed by COMT : mechanism and structural biology. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-enzymatic-methyl-transfer-catalysed-by-comt-mechanism-and-structural-biology(a5c9f031-6bb8-4805-a409-83b849ba32ad).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.804098

Chicago Manual of Style (16^th Edition):

Czarnota, Sylwia. “A study of enzymatic methyl transfer catalysed by COMT : mechanism and structural biology.” 2019. Doctoral Dissertation, University of Manchester. Accessed January 22, 2021. https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-enzymatic-methyl-transfer-catalysed-by-comt-mechanism-and-structural-biology(a5c9f031-6bb8-4805-a409-83b849ba32ad).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.804098.

MLA Handbook (7^th Edition):

Czarnota, Sylwia. “A study of enzymatic methyl transfer catalysed by COMT : mechanism and structural biology.” 2019. Web. 22 Jan 2021.

Vancouver:

Czarnota S. A study of enzymatic methyl transfer catalysed by COMT : mechanism and structural biology. [Internet] [Doctoral dissertation]. University of Manchester; 2019. [cited 2021 Jan 22]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-enzymatic-methyl-transfer-catalysed-by-comt-mechanism-and-structural-biology(a5c9f031-6bb8-4805-a409-83b849ba32ad).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.804098.

Council of Science Editors:

Czarnota S. A study of enzymatic methyl transfer catalysed by COMT : mechanism and structural biology. [Doctoral Dissertation]. University of Manchester; 2019. Available from: https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-enzymatic-methyl-transfer-catalysed-by-comt-mechanism-and-structural-biology(a5c9f031-6bb8-4805-a409-83b849ba32ad).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.804098

Georgia State University

28. Ngac, Phuong K. Determination of Mouth-level Exposure to Catechol in Mainstream Cigarette Smoke.

Degree: MS, Chemistry, 2018, Georgia State University

URL: https://scholarworks.gsu.edu/chemistry_theses/124

► Smokers’ mouth-level exposure to catechol, a potent co-carcinogen generated in the combustion of cigarette tobacco and transferred in the resulting mainstream cigarette smoke (MSS),… (more)

Subjects/Keywords: Catechol; Solanesol; Mainstream smoke; Mouth-level exposure; Cigarette

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APA (6^th Edition):

Ngac, P. K. (2018). Determination of Mouth-level Exposure to Catechol in Mainstream Cigarette Smoke. (Thesis). Georgia State University. Retrieved from https://scholarworks.gsu.edu/chemistry_theses/124

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ngac, Phuong K. “Determination of Mouth-level Exposure to Catechol in Mainstream Cigarette Smoke.” 2018. Thesis, Georgia State University. Accessed January 22, 2021. https://scholarworks.gsu.edu/chemistry_theses/124.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ngac, Phuong K. “Determination of Mouth-level Exposure to Catechol in Mainstream Cigarette Smoke.” 2018. Web. 22 Jan 2021.

Vancouver:

Ngac PK. Determination of Mouth-level Exposure to Catechol in Mainstream Cigarette Smoke. [Internet] [Thesis]. Georgia State University; 2018. [cited 2021 Jan 22]. Available from: https://scholarworks.gsu.edu/chemistry_theses/124.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ngac PK. Determination of Mouth-level Exposure to Catechol in Mainstream Cigarette Smoke. [Thesis]. Georgia State University; 2018. Available from: https://scholarworks.gsu.edu/chemistry_theses/124

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

29. Fan, Ka Wai. Synthesis of functional polymeric materials via redox-facilitated self-polymerization using novel N-heterocyclic cathechol derivatives.

Degree: Centre for Advanced Macromolecular Design, 2016, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/57082 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42454/SOURCE02?view=true

► Poly(dopamine) has been actively involved in the development of a wide spectrum of applications ascribed to its chemical versatility and unique properties. This biomimetic functional… (more)

▼ Poly(dopamine) has been actively involved in the development of a wide spectrum of applications ascribed to its chemical versatility and unique properties. This biomimetic functional polymer is generated when dopamine undergoes redox-facilitated self-polymerization, a technique which is also applicable to a range of natural occurring compounds. Polymers generated from these compounds possess functionalities and properties which poly(dopamine) cannot offer. This dissertation describes the extension of the self-polymerization chemistry onto new synthetic monomer candidates which generate polymers with similar structure but different performance to poly(dopamine).Several heterocyclic catechol derivatives were synthesized, with 5,6-dihydroxy-1H-indazole (DHI) and 5,6-dihydroxy-1H-benzimidazole (DHBI) exhibiting the most promising self-polymerizing ability when subjected to an oxidizing environment. DHI was not able to form polymer coating. It was thus copolymerized with dopamine. The resulting copolymer inherited the low cytotoxicity and coating ability of poly(dopamine), while having pyrazole moieties integrated into the structure as ligands in addition to catechol groups. In contrast, DHBI was capable of forming polymer coatings which modified properties of the coated surface while exhibiting comparable thermal stability to poly(dopamine). Properties of DHBI-based polymer were found tailorable through the integration of desired C-2-substituent during monomer synthesis.The potential to exploit the DHI-dopamine copolymer as a coordination platform was investigated. Through the 67Ga and 64Cu radiolabeling experiments, the copolymer was found possessing pH dependent binding and release behaviors. The release rate of metal species was also found dependent on their compatibility with the hardness of the ligands carried by the copolymer. Prototypes of nanocarriers were fabricated with the copolymer in the form of nanocapsules, which were decorated with hydrophilic poly[oligo(ethylene glycol) methyl ether acrylate] brushes via one pot in situ grafting-from RAFT polymerization. The presence of polymer brushes was found influential to the loading capacity and metal retention of the nanocapsules. This work exemplifies the possibility to rapidly expand the range of monomers with redox-facilitated self-polymerizing ability through the synthetic route. The generated functional polymers possess the potential to be employed by a variety of applications. Advisors/Committee Members: Setterlund, Per, Centre for Advanced Macromolecular Design, Faculty of Engineering, UNSW, Granville, Anthony, TDK Research Solutions, Stenzel, Martina, Chemistry, Faculty of Science, UNSW.

Subjects/Keywords: Benzimidazole; Poly(dopamine); Indazole; Catechol; Functional materials; Polymer coatings

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Fan, K. W. (2016). Synthesis of functional polymeric materials via redox-facilitated self-polymerization using novel N-heterocyclic cathechol derivatives. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/57082 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42454/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Fan, Ka Wai. “Synthesis of functional polymeric materials via redox-facilitated self-polymerization using novel N-heterocyclic cathechol derivatives.” 2016. Doctoral Dissertation, University of New South Wales. Accessed January 22, 2021. http://handle.unsw.edu.au/1959.4/57082 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42454/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Fan, Ka Wai. “Synthesis of functional polymeric materials via redox-facilitated self-polymerization using novel N-heterocyclic cathechol derivatives.” 2016. Web. 22 Jan 2021.

Vancouver:

Fan KW. Synthesis of functional polymeric materials via redox-facilitated self-polymerization using novel N-heterocyclic cathechol derivatives. [Internet] [Doctoral dissertation]. University of New South Wales; 2016. [cited 2021 Jan 22]. Available from: http://handle.unsw.edu.au/1959.4/57082 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42454/SOURCE02?view=true.

Council of Science Editors:

Fan KW. Synthesis of functional polymeric materials via redox-facilitated self-polymerization using novel N-heterocyclic cathechol derivatives. [Doctoral Dissertation]. University of New South Wales; 2016. Available from: http://handle.unsw.edu.au/1959.4/57082 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42454/SOURCE02?view=true

30. Ana LÃcia Rodrigues da Silva. Estudos de complexos metÃlicos de RutÃnio com ligantes o-fenilÃnicos e o ligante bifosfÃnico 1,4-bis(difenilfosfino) butano (dppb).

Degree: PhD, 2007, Universidade Federal do Ceará

URL: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2166 ;

►

Neste trabalho descreve-se a sÃntese, caracterizaÃÃo, reatividade e propriedades de novos complexos de rutÃnio com os ligantes o-fenilenodiamina, o-aminofenol, catecol, naftalenodiol, dopamina e adrenalina a… (more)

▼

Neste trabalho descreve-se a sÃntese, caracterizaÃÃo, reatividade e propriedades de novos complexos de rutÃnio com os ligantes o-fenilenodiamina, o-aminofenol, catecol, naftalenodiol, dopamina e adrenalina a partir do complexo precursor mer-[RuIIICl3(dppb)(H2O)]. Descreve-se tambÃm uma nova rota de desidrogenaÃÃo oxidativa do ligante o-fenilenodiamina a partir da interaÃÃo deste com o complexo mer-[RuIIICl3(dppb)(H2O)]. O complexo mer-[RuIIICl3(dppb)(H2O)] Ã extremamente versÃtil como precursor. Ao reagir com o ligante o-fenilenodiamina diretamente, forma uma mistura constituÃda por complexos que contÃm as formas oxidada (bqdi) e reduzida (opda) do ligante o-fenilÃnico, os complexos trans-[RuIICl2(dppb)(bqdi)] e trans-[RuIICl2(dppb)(opda)], que foi confirmada pela observaÃÃo de dois singletos em d 47 e d 26 no espectro de RMN 31P{1H}. Uma tentativa de atribuiÃÃo preliminar sugere que o ligante opda Ã oxidado a bqdi durante a reaÃÃo, conforme mecanismo proposto no presente trabalho. Entretanto, o produto obtido da reaÃÃo entre o ligante o-fenilenodiamina e o complexo mer-[RuIIICl3(dppb)H2O] por meio da lenta adiÃÃo do ligante apresentou apenas um sinal em d 26 no espectro de RMN 31P{1H}, indicando que o complexo trans- [RuIICl2(dppb)(bqdi)] Ã preferencialmente formado. Tal complexo foi caracterizado por anÃlise elementar, tÃcnicas espectroscÃpicas e eletroquÃmicas e sua estrutura determinada por difraÃÃo de raios X. Com o objetivo de reforÃar o mecanismo proposto, realizou-se a sÃntese entre o o ligante o-fenilenodiamina e o complexo [RuIICl2(dppb)(PPh3)]. Neste caso, o centro metÃlico de rutÃnio jÃ se encontra no estado reduzido e o metal nÃo promoverÃ nenhum tipo de mudanÃa no estado de oxidaÃÃo do ligante. Portanto, o produto obtido apresentou apenas um sinal em d 47 no espectro de RMN 31P{1H}, indicando a formaÃÃo do complexo trans-[RuIICl2(dppb)(opda)], caracterizado por microanÃlise, tÃcnicas espectroscÃpicas e eletroquÃmicas e cuja estrutura foi determinada por difraÃÃo de raios X. Os complexos isolados do tipo trans-[RuIICl2(dppb)(X)], onde X = quinona, dopamina e adrenalina e cis-[RuIICl2(dppb)(L)], onde L = o-aminofenol na forma quinonÃide e bqdi, foram caracterizados por espectroscopia eletrÃnica, vibracional e de ressonÃncia magnÃtica nuclear de fÃsforo, alÃm de tÃcnicas eletroquÃmicas, como voltametria cÃclica e de pulso diferencial.

This research work describes the synthesis, characterization, reactivity and properties of new complexes of ruthenium with the ligands o-phenylenediamine, oaminophenol, catechol, naphtalenediol, dopamine and adrenaline and the mer-[RuIIICl3(dppb)(H2O)] complex. Also, it describes a new metal-assisted oxidative dehydrogenation of the interaction o-phenylenediamine ligand and the mer- [RuIIICl3(dppb)(H2O)] complex. The mer-[RuIIICl3(dppb)(H2O)] complex has shown to be a versatile compound as starting material. The reaction of this compound with the o-phenylenediamine ligand produced a mixture of compounds with the bqdi and opda forms of the o-phenylene ligand, the…

Advisors/Committee Members: Alzir Azevedo Batista, Luiz Gonzaga de FranÃa Lopes, Francisco AudÃsio Dias Filho, Jackson Rodrigues de Sousa, Ãcaro de Sousa Moreira.

Subjects/Keywords: QUIMICA INORGANICA; QuÃmica de coordenaÃÃo; bifosfinas; catecol; quinona; Chemistry of coordination; bifosfin; catechol; quinone

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Silva, A. L. R. d. (2007). Estudos de complexos metÃlicos de RutÃnio com ligantes o-fenilÃnicos e o ligante bifosfÃnico 1,4-bis(difenilfosfino) butano (dppb). (Doctoral Dissertation). Universidade Federal do Ceará. Retrieved from http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2166 ;

Chicago Manual of Style (16^th Edition):

Silva, Ana LÃcia Rodrigues da. “Estudos de complexos metÃlicos de RutÃnio com ligantes o-fenilÃnicos e o ligante bifosfÃnico 1,4-bis(difenilfosfino) butano (dppb).” 2007. Doctoral Dissertation, Universidade Federal do Ceará. Accessed January 22, 2021. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2166 ;.

MLA Handbook (7^th Edition):

Silva, Ana LÃcia Rodrigues da. “Estudos de complexos metÃlicos de RutÃnio com ligantes o-fenilÃnicos e o ligante bifosfÃnico 1,4-bis(difenilfosfino) butano (dppb).” 2007. Web. 22 Jan 2021.

Vancouver:

Silva ALRd. Estudos de complexos metÃlicos de RutÃnio com ligantes o-fenilÃnicos e o ligante bifosfÃnico 1,4-bis(difenilfosfino) butano (dppb). [Internet] [Doctoral dissertation]. Universidade Federal do Ceará 2007. [cited 2021 Jan 22]. Available from: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2166 ;.

Council of Science Editors:

Silva ALRd. Estudos de complexos metÃlicos de RutÃnio com ligantes o-fenilÃnicos e o ligante bifosfÃnico 1,4-bis(difenilfosfino) butano (dppb). [Doctoral Dissertation]. Universidade Federal do Ceará 2007. Available from: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2166 ;

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