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Reproductive Ecology And Microbial Communities From Wood Duck Nest Boxes In Georgia And Florida, Jake Shurba

All Theses

Wood ducks (Aix sponsa) are an important game species throughout the Atlantic Flyway that was nearly extirpated by the early 20^th century due to overhunting and the loss of habitat. Wood ducks are secondary cavity-nesters that utilize artificial nest boxes and natural cavities. It is reported that the use of nest boxes is likely what led to re-establishment of the species in North America. Where boxes are numerous, overuse of boxes by multiple hens throughout a nesting season can occur and result in a buildup of bacteria, parasites and other potentially detrimental pathogens that can impact egg …

Identification Of Critical Points For Bacterial Contamination In The Microbrewery Environment, Alex Ryan Thompson

All Theses

There are 8,884 craft breweries producing over 23 million barrels of beer in the United States as of 2020. These 23 million barrels of craft beer account for 12.3% of the United States beer consumption in 2020. The American craft beer industry is substantial and needs to protect its product from bacterial contamination.

Overall, beer is a microbially stable product. Beers pH, ethanol levels, CO₂ concentrations, the presence of hop-derived antimicrobial compounds, and low levels of O₂ make beer a highly unfavorable environment for most bacterial species. Furthermore, the brewing process, which involves heat treatments and chemical sanitizers …

Influence Of Environmental Conditions On Biofilm Formation Of Listeria Monocytogenes, Jing Li

All Theses

L. monocytogenes is a Gram-positive bacterium, ubiquitously distributed in the environment. It is the etiologic agent of listeriosis, a food-borne disease affecting humans and a variety of vertebrates. L. monocytogenes can form biofilm which is a multi-cellular layer of adherent bacteria surrounded by an extracellular polysaccharide matrix. Biofilm bacteria are extremely resistant to sanitizers and are difficult to be eradicated, therefore posing a big challenge to food processing industry and food service department.
In this work, we tested the biofilm formation in a number of L. monocytogenes serotypes under different environmental conditions, such as temperatures, pH and media (BHI, LB, …

Electromechanics Of Biological Systems Studied By Scanning Probe Microscopy, Gary Thompson

All Dissertations

The functional role of piezoelectricity and of other modes of electromechanical coupling across the hierarchical structures of biological materials garnered interest many years ago. Many biological materials have been described as exhibiting piezoelectric behavior, from wool fibers to wood planks and even to living mammalian cells, but efforts are on-going towards understanding how electromechanical coupling in biological systems transcends from the molecular to tissue levels.
In pursuit of high-resolution measurements of such hierarchical electromechanical coupling, scanning probe microscopy-based techniques are considered. Piezoresponse force microscopy (PFM) becomes the specific focus of this work, and the nascent development of PFM is reviewed …