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Optical Meets Mechanical: Use Of Luminescence Spectroscopy To Assess Ageing In Biodegradable Films, Louis Colaruotolo Oct 2019

Optical Meets Mechanical: Use Of Luminescence Spectroscopy To Assess Ageing In Biodegradable Films, Louis Colaruotolo

Masters Theses

With the growing concern of the accumulation of plastic-based food packaging waste, the search for bio-based biodegradable packages is on the rise. These materials differ from their petro-based counterparts in their degradation rates, which are much higher in the former. Not only do bio-based biodegradable materials degrade faster during post-usage processes but also they age faster during usage and storage, which affects their performance and functionality. The application of noninvasive testing methods with the capability to report on the matrix’s state could assist in the development of a more ubiquitous way to assess ageing in food packaging, particularly in biodegradable …


Autofluorescence To Study The Effects Of Acid Concentration On Cellular Metabolism In Vitro, Robin L. Raley May 2019

Autofluorescence To Study The Effects Of Acid Concentration On Cellular Metabolism In Vitro, Robin L. Raley

Chemistry & Biochemistry Undergraduate Honors Theses

Ultraviolet (UV) radiation-induced sunburns and their accompanying afflictions are a growing public health concern in the United States. There is a need for techniques that can accurately and non-invasively characterize the physiology of sunburned skin tissue directly after UV-damage and applying a topical skin treatment to relieve pain and promote healing. Two-photon excited fluorescence (TPEF) microscopy and fluorescence lifetime imaging (FLIM) can be used to investigate metabolic processes in live cells through endogenous fluorescence of the cofactors, NADH and FAD. These methods employ the optical redox ratio of FAD/(NADH+FAD), mean NADH lifetime, and the separation of the free and bound …


Quantifying Anthropogenic Indicators And Changes In Dissolved Organic Matter In Coastal Urban Aquatic Ecosystems Exposed To High Tidal Flooding, Gonzalo E. Eyzaguirre Apr 2019

Quantifying Anthropogenic Indicators And Changes In Dissolved Organic Matter In Coastal Urban Aquatic Ecosystems Exposed To High Tidal Flooding, Gonzalo E. Eyzaguirre

Department of Biological Sciences

Sea-level rise is causing an increase in tidal flooding in coastal urban areas. Extreme high tides, also known as king tides, are peak tide moments in which tidal amplitude is increased and shallow groundwater flows from the underlying water table are introduced. During tidal flooding in urban areas, accumulated anthropogenic indicators of different water sources are released from groundwater to surface waters, but how these tidal events affect the contributions of different water sources to urban flood waters is uncertain. We quantified tracers of anthropogenic origin including fluoride, fecal coliform bacteria, as well as dissolved organic carbon (DOC) concentrations and …


Effects Of Electrical Stimulation On Glioma Cells In Vitro With Implications For Treating Chronic Pain: Development Of A Model System, David C. Platt Apr 2019

Effects Of Electrical Stimulation On Glioma Cells In Vitro With Implications For Treating Chronic Pain: Development Of A Model System, David C. Platt

Theses and Dissertations

Glial cells comprise over 70% of the central nervous system cells and exhibit diverse functions including regulation of synaptic transmission, neuron protection/repair, maintenance of neuronal metabolism, and are implicated in the development of persistent neuropathic pain. In addition, a perturbation in the concentration of intracellular reactive oxygen species (ROS) and reactive nitrogen species (RNS) has likewise been associated with the development of a chronic pain state. This perturbation in ROS/RNS creates an environment of oxidative stress. However, the mechanism by which the pain signal transmission is modulated, and the roles ROS play in the perpetuation of the pain state are …


L-Tryptophan Adsorption Differentially Changes The Optical Behaviour Of Pseudo-Enantiomeric Cysteine-Functionalized Quantum Dots: Towards Chiral Fluorescent Biosensors, Faezeh Askari, Abbas Rahdar, John F. Trant Feb 2019

L-Tryptophan Adsorption Differentially Changes The Optical Behaviour Of Pseudo-Enantiomeric Cysteine-Functionalized Quantum Dots: Towards Chiral Fluorescent Biosensors, Faezeh Askari, Abbas Rahdar, John F. Trant

Chemistry and Biochemistry Publications

Water-soluble chiral graphene quantum dots (GQDs) with a strong blue emission were synthesized by covalently immobilizing l-cysteine or d-cysteine onto the GQDs. Either the amine or the thiol group of cysteine was used to make the bond through amide coupling or thiol-ene click chemistry respectively. The functionalized chiral GQDs were the characterized by FT-IR and UV–vis. The enantiomeric pairs exhibit equal but opposite bands in circular dichroism spectra suggesting that there is no difference in the efficacy of conjugation. The fluorescent response of these chiral GQDs when exposed to l-tryptophan was then studied. The fluorescence of the amide-conjugated GQDs was …


Cpef Is The Bilin Lyase That Ligates The Doubly Linked Phycoerythrobilin On Phycoerythrin In The Cyanobacterium Fremyella Diplosiphon, Wendy M. Schluchter, R. B. Cole, D. M. Kehoe, M. N. Boutaghou, J. A. Karty, A. Gutu, L. S. Hernandez, J. P. Frick, C. V. Hernandez, C. M. Kronfel Jan 2019

Cpef Is The Bilin Lyase That Ligates The Doubly Linked Phycoerythrobilin On Phycoerythrin In The Cyanobacterium Fremyella Diplosiphon, Wendy M. Schluchter, R. B. Cole, D. M. Kehoe, M. N. Boutaghou, J. A. Karty, A. Gutu, L. S. Hernandez, J. P. Frick, C. V. Hernandez, C. M. Kronfel

Biological Sciences Faculty Publications

Phycoerythrin (PE) is a green light-absorbing protein present in the light-harvesting complex of cyanobacteria and red algae. The spectral characteristics of PE are due to its prosthetic groups, or phycoerythrobilins (PEBs), that are covalently attached to the protein chain by specific bilin lyases. Only two PE lyases have been identified and characterized so far, and the other bilin lyases are unknown. Here, using in silico analyses, markerless deletion, biochemical assays with purified and recombinant proteins, and site-directed mutagenesis, we examined the role of a putative lyase-encoding gene, cpeF, in the cyanobacterium Fremyella diplosiphon. Analyzing the phenotype of the cpeF deletion, …


Influence Of Sporulation And Germination Behavior Of Bacillus Licheniformis On Microbial Quality Of Skim Milk Powder, Nancy Awasti Jan 2019

Influence Of Sporulation And Germination Behavior Of Bacillus Licheniformis On Microbial Quality Of Skim Milk Powder, Nancy Awasti

Electronic Theses and Dissertations

This dissertation includes modeling of sporulation and germination behavior of Bacillus licheniformis strains during raw milk holding, tracking the survival of sporeformers and spores of high sporulating Bacillus strain during skim milk powder manufacturing. In addition, preliminary studies were done to standardize a rapid spore detection technique by using ratiometric fluorescence. To understand the role of strain variability during raw milk holding conditions, population dynamics of two strains of Bacillus licheniformis, ATCC 6634 and 14580, were modeled as a function of temperature (4.0 -12.0˚ C) and duration (0 - 72 h), using regression analysis. Based on initial spiking of vegetative …


Significance Of Rna 2'-5' Linkage And Metal-Ion Mediated Base Pairs, Fusheng Shen Jan 2019

Significance Of Rna 2'-5' Linkage And Metal-Ion Mediated Base Pairs, Fusheng Shen

Legacy Theses & Dissertations (2009 - 2024)

It has been known that the template-directed RNA chemical replication reaction produces mixture of backbones containing both 3’-5’ and 2’-5’ linkages. This backbone heterogeneity has been a significant problem in studying the emergence of RNA World from the prebiotic chemistry. However, very recently, it is reported that FMN binding aptamer and a hammerhead ribozyme are still able to retain considerable functions in the presence of certain 2’-5’ linkages, indicating that RNA backbones may be quite flexible and this backbone heterogeneity problem may not be as severe as originally thought. This finding also brings two related important questions: First, how does …


Cloning The Vision Related G Protein Transducin For Live Cell Fluorescence Studies, Deanna M. Bowman Jan 2019

Cloning The Vision Related G Protein Transducin For Live Cell Fluorescence Studies, Deanna M. Bowman

Williams Honors College, Honors Research Projects

G coupled protein receptors (GCPR) are one of the largest families of receptors and mediate a variety of biological responses. Rhodopsin is the largest family and aids in sight, the α-subunit of the GCPR complex in extremely important to the activation and downstream signaling effects of GCPR. The α-subunit contains a small trans-domain portion and in this project the sequence of that portion will be inserted into a vector containing a fluorescent tag. These vectors will then be used to collect fluorescent cross correlation spectroscopy or FCCS data. The unit was cloned using assembly methods that include PCR and purification …