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Marine biofouling has troubled mankind, both environmentally and economically, since they set sail, resulting in many undesired consequences such as increased drag, reduced maneuverability, increased fuel consumption and greenhouse gas emissions, and heightened maintenance costs. This problem is highly complex as it involves more than 4000 marine organisms with varying modes of adhesion and surface preferences as well as many aquatic environments. The common state-of-the-art approaches to contend with marine biofouling on the submerged surfaces of ships in seawater has antifouling (AF) and fouling-release (FR) surfaces. As AF coating systems utilize biocides which are often toxic to the environment to prevent settlement of biofoulants, the endeavors have been shifted towards non-toxic FR marine system. Many FR systems take advantage of low surface energy and modulus polydimethylsiloxane (PDMS) on their surface, while the recent attempts explored the simultaneous effect of PDMS and hydrophilic moieties (i.e. polyethylene glycol (PEG) or zwitterionic polymers) on an FR surface, known as amphiphilic surfaces. Thus, the work in this dissertation focused on attaining amphiphilic surfaces with desirable FR performance. The studies in this dissertation were investigated to deliver two goals: 1) Enhancing the (FR) fouling-release performance of previously developed coating systems; 2) Introducing novel fouling-release marine coatings with set criteria. To address the former, a series of amphiphilic additives containing PDMS and hydrophilic polymers (zwitterionic-based or PEG) were prepared in chapters two-five. These additives were incorporated in several previously developed FR coating systems in order to modify their surfaces and enhance their FR performance. To address the latter, two amphiphilic marine coating systems were explored for accessing durable, non-toxic, and effective FR surfaces using epoxy-amine crosslinking chemistry. Overall, the studies in this dissertation not only demonstrated viable FR surfaces with desirable performance against several representative marine organisms such as N. incerta, U. linza, C. lytica, barnacles, and mussels but also contributed a deeper understanding about the effect of amphiphilicity concentration/balance on surface and FR properties.

Purpose: Inflammation is characterized by complex interactions between pro- and anti- inflammatory cytokines. Recent research has probed the role of the nervous system in inflammation, part of which includes the cholinergic anti-inflammatory pathway that regulates immunologically-mediated inflammation. In this pathway, norepinephrine release from the splenic nerves binds to beta-2-adrenergic receptors on T cells, causing release of acetylcholine (ACh). ACh subsequently suppresses macrophage production and release of pro-inflammatory cytokines. The purpose of this project is to quantify ACh release from isolated murine splenocytes when challenged with different mediators that stimulate T cells in this pathway. Methods:Our method utilizes liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) for quantification of ACh and choline (Ch) in cell culture media. The developed LC-MS/MS method utilizes an isocratic separation (14% 10mM ammonium formate, pH 3, and 86% acetonitrile) on an Atlantis HILIC column (2.1 x 100 mm, 3 micron). The MS operates in positive electrospray (+ESI) mode, monitoring ions specific for ACh, Ch, and their corresponding deuterium labeled internal standards. The calibration range for ACh was 0.01 - 5 micrograms/ml (0.068 - 34 mM) and 10 - 50 micrograms/ml (96 - 480 mM) for Ch. Cell culture media contained neostigmine (0.5 mM) to inhibit cholinesterase. Cell culture media samples are prepared by freeze drying, reconstituting in acetonitrile, and filtering (0.2micron). Potential loss of ACh through degradation during cell culture was evaluated by monitoring d4-labeled ACh with and without the presence of splenocytes for 4 and 24 hours. Splenocytes were challenged with saline (control) or 1 mM (-) isoproterenol for 4 and 24 hours in the next set of experiments, and ACh in the medium was quantified. We also evaluated separate and combined effects of isoproterenol and activation of T cells with CD3 and CD28 antibodies on ACh release. Results:Correlation coefficients (R2) indicate linearity for ACh and Ch in culture media in the calibration range. During the six-min separation, ACh elutes at 3.8 min and Ch at 5.1 min. Deuterium-labeled ACh, when incubated in cell culture media for 4 and 24 hours, with and without splenocytes, showed a small but statistically significant loss of ACh after 24 h compared to 0 time media controls. However, the average loss of ACh was less than 10% and was not affected by the presence of splenocytes, suggesting that it was due to chemical hydrolysis. Incubation for 4 hr with and without splenocytes did not affect recovery of ACh. Treatment of splenocytes with isoproterenol for 4 hours did not cause significant release of ACh. However, significant release of ACh was detected after 24 hours exposure to isoproterenol or T cell activation. Media from untreated splenocytes had an ACh concentration of 0.14 +/- 0.07 mcg/mL. Isoproterenol treated had 0.28 +/- 0.14 mcg/mL, T-cell activated had 0.32 +/- 0.17 mg/mL, and isoproterenol + T-cell activation had 0.47 +/- 0.16 mcg/mL. Using a 1-way analysis of variance, statistically significant differences were detected between each of these groups. Conclusion: The developed LC-MS/MS assay for quantification of ACh and Ch in cell culture media can be applied to the investigation of the cholinergic anti-inflammatory pathway in isolated splenocytes. Statistically significant differences in ACh release between control splenocytes and those treated with isoproterenol and T-cell activation can be detected. Quantitative investigation of this pathway helps provide an improved understanding of ACh dynamics as a mediator released from leukocytes. Further studies using this model and methodology will provide novel insights into cholinergic anti-inflammatory mechanisms and other immunomodulatory actions of non-neuronal ACh.

As of now, the environmental issue is very topical and there is also an underutilization of different biological material where these can be used in ways that are typically not thought of. One way to increase the degree of utilization is to convert various biomasses such as natural rubber, olive pits, wood chips, and reed pellets into biochar. These biochars can then be added to materials, such as polymers, to improve their reaction-to-fire properties with a low impact on the environment. The process to convert biomasses into biochars, takes place through so-called pyrolysis, i.e., heating under high temperatures and low oxygen concentrations. During pyrolysis, the volatile substances in the biomasses are released and a material is left behind where the compounds that can sustain fire are minimal and a carbon skeleton consisting of strong C-C covalent bonds is prevalent. This biochar then has significantly different material properties compared to its corresponding biomass, where one of the differences is its improved reaction-to-fire properties. This study aims to investigate whether it is possible to determine the final reaction-to-fire properties of different biochars based on the corresponding biomass and its chemical composition. The basis of this study consists of a literature review, laboratory experiments and an analysis. The literature review has been carried out to find the chemical composition of the various biomasses, the laboratory experiments has been carried out to obtain the reaction-to-fire properties of said biomasses and biochars, and the analysis to determine the possibility of predicting the final reaction-to-fire properties of various biochars. The results obtained in this study are that despite the unfavorable reaction-to-fire properties of natural rubber, biochar made from natural rubber had the most desirable reaction-to-fire properties (i.e., fire safe). Of the seven parameters assessed for its reaction-to-fire properties, natural rubber performed worst in five of these compared to the remaining biomasses. However, after conversion to biochar, rubber had the best parameters in three out of five cases where the two additional parameters could not be assessed as these are based on the specimen igniting, which they did not. The parameters in which biochar made from natural rubber obtained the best results were peak heat release rate (PHRR), total heat released per unit area (THRPUA), and maximum average rate of heat emission (MARHE). However, biochar made from natural rubber also obtained the worst results in terms of time to peak heat release rate (TTPHRR) and fire growth rate (FIGRA), where FIGRA is inversely proportional to TTPHRR. Although the lignocellulosic biomasses showed difference in their chemical composition, no major difference in PHRR, THRPUA, and MARHE could be detected between them when their corresponding biochars were tested in the cone calorimeter. The conclusions that can be drawn from this study are that it is possible to predict the final reaction-to-fire properties of the lignocellulosic biochars since they react almost equally when exposed to fire. However, more tests and studies are required to be able to predict the final reaction-to-fire properties of the non-lignocellulosic biochars. This is to understand the chemical compounds and bonds that are formed during pyrolysis, as well as how these affect the biochar’s reaction-to-fire properties.

Manuscript No. 1 Recent research has indicated that low nest success and juvenile survival of Greater Sage-Grouse may be responsible for population declines. Recent technological advances in micro-transmitters have made radio-telemetry studies on Sage-Grouse chicks more common. Radio-telemetry enables monitoring of individual chicks and broods during a critical period of their life history. The exact cause of low chick recruitment in Strawberry Valley has not been well understood. In 2006, a chick mortality study using micro-transmitters was initiated to (1) determine the causes of chick mortality, (2) calculate overall chick survival, (3) compare chick survival in the Strawberry Valley population to published reports, (4) monitor brood movements, and (5) suggest management strategies for mitigation of chick mortality. Survival data on radio-marked chicks were analyzed using a known fate model in program MARK. Chick survival in Strawberry Valley was greater than all reported estimates from other studies. Our study did not identify any unsuspected causes of chick mortality, and the cumulative effect of stressing chicks, hens, and broods was not deemed worth the benefit, especially in a population recovery setting like Strawberry Valley. We do not recommend the use of radio-telemetry on Sage-Grouse chicks in recovering or sensitive populations. Manuscript No. 2 In 2003, we began translocating Greater Sage-Grouse into the Strawberry Valley of central Utah, in an attempt to recover the dwindling population found therein. Prior to 2006 all translocated Sage-Grouse were released within 250 m of the only active lek in Strawberry Valley while males were actively strutting. A prolonged winter in 2006 delayed normal lekking activity in Strawberry Valley. As a result 61 (59%) of the 103 sage-grouse translocated in 2006 were not released near an active lek. We analyzed the influence that release timing, hen age, body mass, and source population had on mortality, flocking, and dispersal distance of translocated hens in 2006. We found that mortality and flocking rates were not influenced by release timing, hen age, body mass, or source population. Dispersal distances for hens released near a lek with actively strutting males were significantly less than distances of hens released near an inactive lek. We believe that releasing translocated Sage-Grouse near a lek with actively strutting males is an essential technique for Greater Sage-Grouse translocations. We recommend that other Sage-Grouse translocation efforts employ this method to increase the likelihood of success.

Pollution is one of the greatest concerns with pulverized coal combustion. With tightening standards on pollution emissions, more information is needed to create better design models. Burner modifications are the most efficient changes that can be made to assure sufficient carbon burnout and low NOx emissions. Experiments were performed in the BYU Flat Flame Burner (FFB) lab, operating under fuel rich conditions for pyrolysis experiments and fuel lean conditions for char oxidation experiments. Effects of temperature, coal rank, residence time, and post flame oxygen content on mass release, nitrogen release, and reactivity were examined. Elemental and Inductively coupled plasma (ICP) analyses were used to determine the mass and nitrogen release of coals and chars. FT-IR was used to determine gas phase nitrogen compositions on selected experiments. Results of char oxidation experiments were fit to a first-order model to obtain an Arrhenius pre-exponential factor, while activation energies were approximated using a published correlation. CPD model calculations were used to find experimental residence times and particle diameters that obtained full pyrolysis yields. Oxy-fuel experiments were performed by switching the burner diluent gas from N2 to CO2. Oxy-fuel experiments exhibited a rank effect in nitrogen release. Bituminous coal tests showed no statistically significant difference in mass or nitrogen release between the two conditions. A sub-bituminous coal exhibited a greater mass and nitrogen release for the same residence time under the CO2 environment, which could be due to early gasification of the char. Two samples of a chemically treated coal with different additive concentrations were tested against an untreated sample for combustion enhancement. The treated samples showed an increase on the order of 15% absolute in pyrolysis yield compared to the untreated sample. An increase in reactivity on the order of 35% was observed for the higher concentrated sample, but not for the lower treatment concentration. Gas phase nitrogen measurements showed both HCN and NH3 at the 1300 K gas temperature condition. HCN and NH3 release during pyrolysis was largely rank dependent, with more HCN formed initially than NH3 for 5 of the 6 samples. However, a Polish bituminous coal was found to have more NH3 than HCN. These nitrogen species data can be used to evaluate or refine nitrogen transformation mechanisms.

Bioactive compounds, such as curcumin, lutein, coenzyme Q10, β-carotene, cholecalciferol, astaxanthin, and β-sitosterol, have antioxidant and anti-inflammatory properties that promote health, but their low solubility, fast metabolism, and degradation have made it difficult to fully harness their potential. Encapsulation techniques, such as nano and microencapsulation using food-based biopolymers, have been employed to address these challenges. However, research efforts in protein-based delivery have mainly focused on encapsulation without considering structural, physicochemical, and matrix compatibility, which is tedious, unsustainable, and not cost-effective. Hence, this thesis reports the structural basis of guest-host interaction in the gastrointestinal delivery of lipophilic bioactive compounds using protein-based vehicles. This research employed fluorescence quenching techniques to estimate the influence of protein modification, fractionation and ionic strength on the nature and strength of interactions between protein and bioactive compounds. Morphological examination was carried out with transmission electron microscopy, confocal and widefield fluorescence microscopy whereas the sizes of the nano and micro-complexes was measured with dynamic light scattering techniques. Thermal stability was measured with differential scanning calorimetry and functional group characterization done with Fourier Transform infrared spectroscopy. Encapsulation efficiency was estimated by UV-Visible spectroscopy whereas in vitro bioactive compound release study was carried out in simulated salivary, gastric and intestinal fluids. Cytotoxicity assessment was estimated by calcein leakage assay. The study showed that protein modification affects the strength of protein-curcumin interaction and encapsulation efficiency. Pea protein succinylation increased electrostatic interaction with chitosan but decreased protein-curcumin interaction. Pea glutelin, albumin and globulin fractions showed different binding strengths with curcumin and the protein hydrophobicity and encapsulation efficiency correlated positively with the binding strength. The study also investigated the impact of bioactive compound lipophilicity and physiological ionic strength on the interaction between protein and bioactive compound. Lipophilicity influenced the strength of protein-bioactive compound interaction, while ionic strength changed the mode of interaction from static to static-dynamic quenching. The morphology of the nano and micro complexes formed with protein varied depending on the nature of encapsulated bioactive compound. Finally, bio-nano interaction involving giant unilamellar vesicles and curcumin-loaded pea protein of various surface functionalities as model biomembrane and nanoparticles respectively, was investigated. The result showed that while the protein/chitosan shell stabilizes bioactive compounds from degradation, the bioactive compound modulates their interaction with biomembrane. Overall, this work has demonstrated that for a rational design of protein-based nano/micro-encapsulation system, it is essential to consider the influence of the structural and physicochemical properties of proteins and bioactive compounds, stabilizing intermolecular forces, ionic strength of the environment, lipophilicity of the bioactive compounds, mechanism of release and modulation of cytotoxicity by bioactive compound. For instance, in high ionic strength solution, the stoichiometric ratio between protein carrier and bioactive compounds influences the stability of the complex. Balancing the intermolecular forces in the shell and core of bilayer complexes is essential for the stability of nanocomplexes and the presence of bioactive compound stabilizes the macromolecular carrier to minimal biomembrane disruption.

This thesis aims to clarify the use of Excel for capacity planning, how an excel-based capacityplanning tool works, and to present a way to implement a web system suitable for ad-hoc capacity and release planning. Capacity design is a critical part of flexible software development teams. Excel spreadsheets are flexible but not ideal for large organizations where many users have access to and can change planning concurrently. The existing tool received low ratings in terms of helpfulness, robustness to the inappropriate user, universality, flexibility, and aesthetics but performed quite well in clarity, consistency, memorability, overall efficiency, and third-party safety. The tool had some additional benefits, including calculating team capacity, preventing overplanning of individual development teams, and the ability to register the outcome of past planning periods. We implemented a web system based on Blazor Web to support the tasks provided by the existing tool, including capacity planning and release planning. The web system also supported role-based authorization. This web system was evaluated in a usability survey and maintained most of the provided functionality of the existing tool while avoiding some of the tool’s usability-related problems.

Corrosion and metal release mechanisms of CoCrMo alloys are at human biological conditions not fully understood. The main objective of this master thesis was to investigate whether the Vroman effect influences the extent of metal release from CoCrMo alloy in mixed protein solutions. The project focuses on the corrosion properties and release of cobalt (Co), chromium (Cr) and molybdenum (Mo) from a CoCrMo alloy into simulated physiological solutions of pH 7.2-7.4 in the presence of proteins. The metal release study was performed in phosphate buffered saline (PBS) for 4 and 24 h at 37 °C with and without different concentration of proteins (bovine serum albumin-BSA and fibrinogen-Fbn from bovine plasma). In order to investigate whether any Vroman effect could affect the extent of released metals in solutions, sequential tests were performed by sampling after 1, 4, 6 and 24 h in solutions that were partially replenished after 5 h. Significant metal-induced protein aggregation and precipitation were observed in solutions of physiologically-relevant protein concentrations (40 g/L BSA and 2.67 g/L Fbn). Cr was strongly enriched in the surface oxide of CoCrMo after exposure in all solutions. This was for all solutions accompanied by metal release processes dominated by Co. Based on electrochemical investigations, the electrochemical activity did not increase, but rather decreased, in protein-containing solutions as compared to PBS alone. This could possibly be explained by blocking of cathodic areas as a result of protein adsorption.